linux-stable/arch/m68k/mac/via.c

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License cleanup: add SPDX GPL-2.0 license identifier to files with no license Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-01 14:07:57 +00:00
// SPDX-License-Identifier: GPL-2.0
/*
* 6522 Versatile Interface Adapter (VIA)
*
* There are two of these on the Mac II. Some IRQs are vectored
* via them as are assorted bits and bobs - eg RTC, ADB.
*
* CSA: Motorola seems to have removed documentation on the 6522 from
* their web site; try
* http://nerini.drf.com/vectrex/other/text/chips/6522/
* http://www.zymurgy.net/classic/vic20/vicdet1.htm
* and
* http://193.23.168.87/mikro_laborversuche/via_iobaustein/via6522_1.html
* for info. A full-text web search on 6522 AND VIA will probably also
* net some usefulness. <cananian@alumni.princeton.edu> 20apr1999
*
* Additional data is here (the SY6522 was used in the Mac II etc):
* http://www.6502.org/documents/datasheets/synertek/synertek_sy6522.pdf
* http://www.6502.org/documents/datasheets/synertek/synertek_sy6522_programming_reference.pdf
*
* PRAM/RTC access algorithms are from the NetBSD RTC toolkit version 1.08b
* by Erik Vogan and adapted to Linux by Joshua M. Thompson (funaho@jurai.org)
*
*/
#include <linux/clocksource.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/irq.h>
#include <asm/macintosh.h>
#include <asm/macints.h>
#include <asm/mac_via.h>
#include <asm/mac_psc.h>
#include <asm/mac_oss.h>
volatile __u8 *via1, *via2;
int rbv_present;
int via_alt_mapping;
EXPORT_SYMBOL(via_alt_mapping);
static __u8 rbv_clear;
/*
* Globals for accessing the VIA chip registers without having to
* check if we're hitting a real VIA or an RBV. Normally you could
* just hit the combined register (ie, vIER|rIER) but that seems to
* break on AV Macs...probably because they actually decode more than
* eight address bits. Why can't Apple engineers at least be
* _consistently_ lazy? - 1999-05-21 (jmt)
*/
static int gIER,gIFR,gBufA,gBufB;
/*
* On Macs with a genuine VIA chip there is no way to mask an individual slot
* interrupt. This limitation also seems to apply to VIA clone logic cores in
* Quadra-like ASICs. (RBV and OSS machines don't have this limitation.)
*
* We used to fake it by configuring the relevant VIA pin as an output
* (to mask the interrupt) or input (to unmask). That scheme did not work on
* (at least) the Quadra 700. A NuBus card's /NMRQ signal is an open-collector
* circuit (see Designing Cards and Drivers for Macintosh II and Macintosh SE,
* p. 10-11 etc) but VIA outputs are not (see datasheet).
*
* Driving these outputs high must cause the VIA to source current and the
* card to sink current when it asserts /NMRQ. Current will flow but the pin
* voltage is uncertain and so the /NMRQ condition may still cause a transition
* at the VIA2 CA1 input (which explains the lost interrupts). A side effect
* is that a disabled slot IRQ can never be tested as pending or not.
*
* Driving these outputs low doesn't work either. All the slot /NMRQ lines are
* (active low) OR'd together to generate the CA1 (aka "SLOTS") interrupt (see
* The Guide To Macintosh Family Hardware, 2nd edition p. 167). If we drive a
* disabled /NMRQ line low, the falling edge immediately triggers a CA1
* interrupt and all slot interrupts after that will generate no transition
* and therefore no interrupt, even after being re-enabled.
*
* So we make the VIA port A I/O lines inputs and use nubus_disabled to keep
* track of their states. When any slot IRQ becomes disabled we mask the CA1
* umbrella interrupt. Only when all slot IRQs become enabled do we unmask
* the CA1 interrupt. It must remain enabled even when cards have no interrupt
* handler registered. Drivers must therefore disable a slot interrupt at the
* device before they call free_irq (like shared and autovector interrupts).
*
* There is also a related problem when MacOS is used to boot Linux. A network
* card brought up by a MacOS driver may raise an interrupt while Linux boots.
* This can be fatal since it can't be handled until the right driver loads
* (if such a driver exists at all). Apparently related to this hardware
* limitation, "Designing Cards and Drivers", p. 9-8, says that a slot
* interrupt with no driver would crash MacOS (the book was written before
* the appearance of Macs with RBV or OSS).
m68k: Mac nubus IRQ fixes (plan E) Some Macs lack a slot interrupt enable register. So the existing code makes disabled and unregistered slot IRQ lines outputs set high. This seems to work on quadras, but does not work on genuine VIAs (perhaps the card still succeeds in pulling the line low, or perhaps because this increases the settle time on the port A input, meaning that the CA1 IRQ could fire before the slot line reads active). Because of this, the nubus_active flags were used to mask IRQs, which is actually worse than the problem it tries to solve. Any interrupt masked by nubus_active will remain asserted and prevent further transitions on CA1. And so the nubus gets wedged regardless of hardware (emulated VIA ASIC, real VIA chip or RBV). The best solution to this hardware limitation of genuine VIAs is to disable the umbrella SLOTS IRQ when disabling a slot on those machines. Unfortunately, this means all slot IRQs get disabled when any slot IRQ is disabled. But it is only a problem when there's more than 1 device using nubus interrupts. Another potential problem for genuine VIAs is an unregistered nubus IRQ. Eventually it will be possible to enable the CA1 interrupt by installing its handler only _after_ all nubus drivers have loaded but _before_ the kernel needs them, at which time this last problem can be fixed. For now it can be worked around: - disable MacOS extensions - don't boot MacOS (use the Emile bootloader instead) - get the bootloaders to disable ROM drivers (Penguin does this for video cards already, don't know about Emile) - physically remove unsupported cards Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-01 20:32:57 +00:00
*/
m68k: Mac nubus IRQ fixes (plan E) Some Macs lack a slot interrupt enable register. So the existing code makes disabled and unregistered slot IRQ lines outputs set high. This seems to work on quadras, but does not work on genuine VIAs (perhaps the card still succeeds in pulling the line low, or perhaps because this increases the settle time on the port A input, meaning that the CA1 IRQ could fire before the slot line reads active). Because of this, the nubus_active flags were used to mask IRQs, which is actually worse than the problem it tries to solve. Any interrupt masked by nubus_active will remain asserted and prevent further transitions on CA1. And so the nubus gets wedged regardless of hardware (emulated VIA ASIC, real VIA chip or RBV). The best solution to this hardware limitation of genuine VIAs is to disable the umbrella SLOTS IRQ when disabling a slot on those machines. Unfortunately, this means all slot IRQs get disabled when any slot IRQ is disabled. But it is only a problem when there's more than 1 device using nubus interrupts. Another potential problem for genuine VIAs is an unregistered nubus IRQ. Eventually it will be possible to enable the CA1 interrupt by installing its handler only _after_ all nubus drivers have loaded but _before_ the kernel needs them, at which time this last problem can be fixed. For now it can be worked around: - disable MacOS extensions - don't boot MacOS (use the Emile bootloader instead) - get the bootloaders to disable ROM drivers (Penguin does this for video cards already, don't know about Emile) - physically remove unsupported cards Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-01 20:32:57 +00:00
static u8 nubus_disabled;
void via_debug_dump(void);
m68k/mac: Disentangle VIA/RBV and NuBus initialization The Nubus subsystem should not be concerned with differences between VIA, RBV and OSS platforms. It should be portable across Macs and PowerMacs. This goal has implications for the initialization code relating to bus locking and slot interrupts. During Nubus initialization, bus transactions are "unlocked": on VIA2 and RBV machines, via_nubus_init() sets a bit in the via2[gBufB] register to allow bus-mastering Nubus cards to arbitrate for the bus. This happens upon subsys_initcall(nubus_init). But because nubus_init() has no effect on card state, this sequence is arbitrary. Moreover, when Penguin is used to boot Linux, the bus is already unlocked when Linux starts. On OSS machines there's no attempt to unlock Nubus transactions at all. (Maybe there's no benefit on that platform or maybe no-one knows how.) All of this demonstrates that there's no benefit in locking out bus-mastering cards, as yet. (If the need arises, we could lock the bus for the duration of a timing-critical operation.) NetBSD unlocks the Nubus early (at VIA initialization) and we can do the same. via_nubus_init() is also responsible for some VIA interrupt setup that should happen earlier than subsys_initcall(nubus_init). And actually, the Nubus subsystem need not be involved with slot interrupts: SLOT2IRQ works fine because Nubus slot IRQs are geographically assigned (regardless of platform). For certain platforms with PDS slots, some Nubus IRQs may be platform IRQs and this is not something that the NuBus subsystem should worry about. So let's invoke via_nubus_init() earlier and make the platform responsible for bus unlocking and interrupt setup instead of the NuBus subsystem. Tested-by: Stan Johnson <userm57@yahoo.com> Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2017-10-27 02:45:24 +00:00
static void via_nubus_init(void);
/*
* Initialize the VIAs
*
* First we figure out where they actually _are_ as well as what type of
* VIA we have for VIA2 (it could be a real VIA or an RBV or even an OSS.)
* Then we pretty much clear them out and disable all IRQ sources.
*/
void __init via_init(void)
{
via1 = (void *)VIA1_BASE;
pr_debug("VIA1 detected at %p\n", via1);
if (oss_present) {
via2 = NULL;
rbv_present = 0;
} else {
switch (macintosh_config->via_type) {
/* IIci, IIsi, IIvx, IIvi (P6xx), LC series */
case MAC_VIA_IICI:
via2 = (void *)RBV_BASE;
pr_debug("VIA2 (RBV) detected at %p\n", via2);
rbv_present = 1;
if (macintosh_config->ident == MAC_MODEL_LCIII) {
rbv_clear = 0x00;
} else {
/* on most RBVs (& unlike the VIAs), you */
/* need to set bit 7 when you write to IFR */
/* in order for your clear to occur. */
rbv_clear = 0x80;
}
gIER = rIER;
gIFR = rIFR;
gBufA = rSIFR;
gBufB = rBufB;
break;
/* Quadra and early MacIIs agree on the VIA locations */
case MAC_VIA_QUADRA:
case MAC_VIA_II:
via2 = (void *) VIA2_BASE;
pr_debug("VIA2 detected at %p\n", via2);
rbv_present = 0;
rbv_clear = 0x00;
gIER = vIER;
gIFR = vIFR;
gBufA = vBufA;
gBufB = vBufB;
break;
default:
panic("UNKNOWN VIA TYPE");
}
}
#ifdef DEBUG_VIA
via_debug_dump();
#endif
/*
* Shut down all IRQ sources, reset the timers, and
* kill the timer latch on VIA1.
*/
via1[vIER] = 0x7F;
via1[vIFR] = 0x7F;
via1[vT1LL] = 0;
via1[vT1LH] = 0;
via1[vT1CL] = 0;
via1[vT1CH] = 0;
via1[vT2CL] = 0;
via1[vT2CH] = 0;
via1[vACR] &= ~0xC0; /* setup T1 timer with no PB7 output */
via1[vACR] &= ~0x03; /* disable port A & B latches */
/*
* SE/30: disable video IRQ
*/
if (macintosh_config->ident == MAC_MODEL_SE30) {
via1[vDirB] |= 0x40;
via1[vBufB] |= 0x40;
}
switch (macintosh_config->adb_type) {
case MAC_ADB_IOP:
case MAC_ADB_II:
case MAC_ADB_PB1:
/*
* Set the RTC bits to a known state: all lines to outputs and
* RTC disabled (yes that's 0 to enable and 1 to disable).
*/
via1[vDirB] |= VIA1B_vRTCEnb | VIA1B_vRTCClk | VIA1B_vRTCData;
via1[vBufB] |= VIA1B_vRTCEnb | VIA1B_vRTCClk;
break;
}
/* Everything below this point is VIA2/RBV only... */
if (oss_present)
return;
if ((macintosh_config->via_type == MAC_VIA_QUADRA) &&
(macintosh_config->adb_type != MAC_ADB_PB1) &&
(macintosh_config->adb_type != MAC_ADB_PB2) &&
(macintosh_config->ident != MAC_MODEL_C660) &&
(macintosh_config->ident != MAC_MODEL_Q840)) {
via_alt_mapping = 1;
via1[vDirB] |= 0x40;
via1[vBufB] &= ~0x40;
} else {
via_alt_mapping = 0;
}
/*
* Now initialize VIA2. For RBV we just kill all interrupts;
* for a regular VIA we also reset the timers and stuff.
*/
via2[gIER] = 0x7F;
via2[gIFR] = 0x7F | rbv_clear;
if (!rbv_present) {
via2[vT1LL] = 0;
via2[vT1LH] = 0;
via2[vT1CL] = 0;
via2[vT1CH] = 0;
via2[vT2CL] = 0;
via2[vT2CH] = 0;
via2[vACR] &= ~0xC0; /* setup T1 timer with no PB7 output */
via2[vACR] &= ~0x03; /* disable port A & B latches */
}
m68k/mac: Disentangle VIA/RBV and NuBus initialization The Nubus subsystem should not be concerned with differences between VIA, RBV and OSS platforms. It should be portable across Macs and PowerMacs. This goal has implications for the initialization code relating to bus locking and slot interrupts. During Nubus initialization, bus transactions are "unlocked": on VIA2 and RBV machines, via_nubus_init() sets a bit in the via2[gBufB] register to allow bus-mastering Nubus cards to arbitrate for the bus. This happens upon subsys_initcall(nubus_init). But because nubus_init() has no effect on card state, this sequence is arbitrary. Moreover, when Penguin is used to boot Linux, the bus is already unlocked when Linux starts. On OSS machines there's no attempt to unlock Nubus transactions at all. (Maybe there's no benefit on that platform or maybe no-one knows how.) All of this demonstrates that there's no benefit in locking out bus-mastering cards, as yet. (If the need arises, we could lock the bus for the duration of a timing-critical operation.) NetBSD unlocks the Nubus early (at VIA initialization) and we can do the same. via_nubus_init() is also responsible for some VIA interrupt setup that should happen earlier than subsys_initcall(nubus_init). And actually, the Nubus subsystem need not be involved with slot interrupts: SLOT2IRQ works fine because Nubus slot IRQs are geographically assigned (regardless of platform). For certain platforms with PDS slots, some Nubus IRQs may be platform IRQs and this is not something that the NuBus subsystem should worry about. So let's invoke via_nubus_init() earlier and make the platform responsible for bus unlocking and interrupt setup instead of the NuBus subsystem. Tested-by: Stan Johnson <userm57@yahoo.com> Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2017-10-27 02:45:24 +00:00
via_nubus_init();
/* Everything below this point is VIA2 only... */
if (rbv_present)
return;
/*
* Set vPCR for control line interrupts.
*
* CA1 (SLOTS IRQ), CB1 (ASC IRQ): negative edge trigger.
*
* Macs with ESP SCSI have a negative edge triggered SCSI interrupt.
* Testing reveals that PowerBooks do too. However, the SE/30
* schematic diagram shows an active high NCR5380 IRQ line.
*/
pr_debug("VIA2 vPCR is 0x%02X\n", via2[vPCR]);
if (macintosh_config->via_type == MAC_VIA_II) {
/* CA2 (SCSI DRQ), CB2 (SCSI IRQ): indep. input, pos. edge */
via2[vPCR] = 0x66;
} else {
/* CA2 (SCSI DRQ), CB2 (SCSI IRQ): indep. input, neg. edge */
via2[vPCR] = 0x22;
}
}
/*
* Debugging dump, used in various places to see what's going on.
*/
void via_debug_dump(void)
{
printk(KERN_DEBUG "VIA1: DDRA = 0x%02X DDRB = 0x%02X ACR = 0x%02X\n",
(uint) via1[vDirA], (uint) via1[vDirB], (uint) via1[vACR]);
printk(KERN_DEBUG " PCR = 0x%02X IFR = 0x%02X IER = 0x%02X\n",
(uint) via1[vPCR], (uint) via1[vIFR], (uint) via1[vIER]);
if (!via2)
return;
if (rbv_present) {
printk(KERN_DEBUG "VIA2: IFR = 0x%02X IER = 0x%02X\n",
(uint) via2[rIFR], (uint) via2[rIER]);
printk(KERN_DEBUG " SIFR = 0x%02X SIER = 0x%02X\n",
(uint) via2[rSIFR], (uint) via2[rSIER]);
} else {
printk(KERN_DEBUG "VIA2: DDRA = 0x%02X DDRB = 0x%02X ACR = 0x%02X\n",
(uint) via2[vDirA], (uint) via2[vDirB],
(uint) via2[vACR]);
printk(KERN_DEBUG " PCR = 0x%02X IFR = 0x%02X IER = 0x%02X\n",
(uint) via2[vPCR],
(uint) via2[vIFR], (uint) via2[vIER]);
}
}
/*
* Flush the L2 cache on Macs that have it by flipping
* the system into 24-bit mode for an instant.
*/
void via_flush_cache(void)
{
via2[gBufB] &= ~VIA2B_vMode32;
via2[gBufB] |= VIA2B_vMode32;
}
/*
* Return the status of the L2 cache on a IIci
*/
int via_get_cache_disable(void)
{
/* Safeguard against being called accidentally */
if (!via2) {
printk(KERN_ERR "via_get_cache_disable called on a non-VIA machine!\n");
return 1;
}
return (int) via2[gBufB] & VIA2B_vCDis;
}
/*
* Initialize VIA2 for Nubus access
*/
m68k/mac: Disentangle VIA/RBV and NuBus initialization The Nubus subsystem should not be concerned with differences between VIA, RBV and OSS platforms. It should be portable across Macs and PowerMacs. This goal has implications for the initialization code relating to bus locking and slot interrupts. During Nubus initialization, bus transactions are "unlocked": on VIA2 and RBV machines, via_nubus_init() sets a bit in the via2[gBufB] register to allow bus-mastering Nubus cards to arbitrate for the bus. This happens upon subsys_initcall(nubus_init). But because nubus_init() has no effect on card state, this sequence is arbitrary. Moreover, when Penguin is used to boot Linux, the bus is already unlocked when Linux starts. On OSS machines there's no attempt to unlock Nubus transactions at all. (Maybe there's no benefit on that platform or maybe no-one knows how.) All of this demonstrates that there's no benefit in locking out bus-mastering cards, as yet. (If the need arises, we could lock the bus for the duration of a timing-critical operation.) NetBSD unlocks the Nubus early (at VIA initialization) and we can do the same. via_nubus_init() is also responsible for some VIA interrupt setup that should happen earlier than subsys_initcall(nubus_init). And actually, the Nubus subsystem need not be involved with slot interrupts: SLOT2IRQ works fine because Nubus slot IRQs are geographically assigned (regardless of platform). For certain platforms with PDS slots, some Nubus IRQs may be platform IRQs and this is not something that the NuBus subsystem should worry about. So let's invoke via_nubus_init() earlier and make the platform responsible for bus unlocking and interrupt setup instead of the NuBus subsystem. Tested-by: Stan Johnson <userm57@yahoo.com> Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2017-10-27 02:45:24 +00:00
static void __init via_nubus_init(void)
{
/* unlock nubus transactions */
if ((macintosh_config->adb_type != MAC_ADB_PB1) &&
(macintosh_config->adb_type != MAC_ADB_PB2)) {
/* set the line to be an output on non-RBV machines */
if (!rbv_present)
via2[vDirB] |= 0x02;
/* this seems to be an ADB bit on PMU machines */
/* according to MkLinux. -- jmt */
via2[gBufB] |= 0x02;
}
/*
* Disable the slot interrupts. On some hardware that's not possible.
* On some hardware it's unclear what all of these I/O lines do.
*/
m68k: Mac nubus IRQ fixes (plan E) Some Macs lack a slot interrupt enable register. So the existing code makes disabled and unregistered slot IRQ lines outputs set high. This seems to work on quadras, but does not work on genuine VIAs (perhaps the card still succeeds in pulling the line low, or perhaps because this increases the settle time on the port A input, meaning that the CA1 IRQ could fire before the slot line reads active). Because of this, the nubus_active flags were used to mask IRQs, which is actually worse than the problem it tries to solve. Any interrupt masked by nubus_active will remain asserted and prevent further transitions on CA1. And so the nubus gets wedged regardless of hardware (emulated VIA ASIC, real VIA chip or RBV). The best solution to this hardware limitation of genuine VIAs is to disable the umbrella SLOTS IRQ when disabling a slot on those machines. Unfortunately, this means all slot IRQs get disabled when any slot IRQ is disabled. But it is only a problem when there's more than 1 device using nubus interrupts. Another potential problem for genuine VIAs is an unregistered nubus IRQ. Eventually it will be possible to enable the CA1 interrupt by installing its handler only _after_ all nubus drivers have loaded but _before_ the kernel needs them, at which time this last problem can be fixed. For now it can be worked around: - disable MacOS extensions - don't boot MacOS (use the Emile bootloader instead) - get the bootloaders to disable ROM drivers (Penguin does this for video cards already, don't know about Emile) - physically remove unsupported cards Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-01 20:32:57 +00:00
switch (macintosh_config->via_type) {
case MAC_VIA_II:
case MAC_VIA_QUADRA:
pr_debug("VIA2 vDirA is 0x%02X\n", via2[vDirA]);
m68k: Mac nubus IRQ fixes (plan E) Some Macs lack a slot interrupt enable register. So the existing code makes disabled and unregistered slot IRQ lines outputs set high. This seems to work on quadras, but does not work on genuine VIAs (perhaps the card still succeeds in pulling the line low, or perhaps because this increases the settle time on the port A input, meaning that the CA1 IRQ could fire before the slot line reads active). Because of this, the nubus_active flags were used to mask IRQs, which is actually worse than the problem it tries to solve. Any interrupt masked by nubus_active will remain asserted and prevent further transitions on CA1. And so the nubus gets wedged regardless of hardware (emulated VIA ASIC, real VIA chip or RBV). The best solution to this hardware limitation of genuine VIAs is to disable the umbrella SLOTS IRQ when disabling a slot on those machines. Unfortunately, this means all slot IRQs get disabled when any slot IRQ is disabled. But it is only a problem when there's more than 1 device using nubus interrupts. Another potential problem for genuine VIAs is an unregistered nubus IRQ. Eventually it will be possible to enable the CA1 interrupt by installing its handler only _after_ all nubus drivers have loaded but _before_ the kernel needs them, at which time this last problem can be fixed. For now it can be worked around: - disable MacOS extensions - don't boot MacOS (use the Emile bootloader instead) - get the bootloaders to disable ROM drivers (Penguin does this for video cards already, don't know about Emile) - physically remove unsupported cards Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-01 20:32:57 +00:00
break;
case MAC_VIA_IICI:
m68k: Mac nubus IRQ fixes (plan E) Some Macs lack a slot interrupt enable register. So the existing code makes disabled and unregistered slot IRQ lines outputs set high. This seems to work on quadras, but does not work on genuine VIAs (perhaps the card still succeeds in pulling the line low, or perhaps because this increases the settle time on the port A input, meaning that the CA1 IRQ could fire before the slot line reads active). Because of this, the nubus_active flags were used to mask IRQs, which is actually worse than the problem it tries to solve. Any interrupt masked by nubus_active will remain asserted and prevent further transitions on CA1. And so the nubus gets wedged regardless of hardware (emulated VIA ASIC, real VIA chip or RBV). The best solution to this hardware limitation of genuine VIAs is to disable the umbrella SLOTS IRQ when disabling a slot on those machines. Unfortunately, this means all slot IRQs get disabled when any slot IRQ is disabled. But it is only a problem when there's more than 1 device using nubus interrupts. Another potential problem for genuine VIAs is an unregistered nubus IRQ. Eventually it will be possible to enable the CA1 interrupt by installing its handler only _after_ all nubus drivers have loaded but _before_ the kernel needs them, at which time this last problem can be fixed. For now it can be worked around: - disable MacOS extensions - don't boot MacOS (use the Emile bootloader instead) - get the bootloaders to disable ROM drivers (Penguin does this for video cards already, don't know about Emile) - physically remove unsupported cards Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-01 20:32:57 +00:00
/* RBV. Disable all the slot interrupts. SIER works like IER. */
via2[rSIER] = 0x7F;
m68k: Mac nubus IRQ fixes (plan E) Some Macs lack a slot interrupt enable register. So the existing code makes disabled and unregistered slot IRQ lines outputs set high. This seems to work on quadras, but does not work on genuine VIAs (perhaps the card still succeeds in pulling the line low, or perhaps because this increases the settle time on the port A input, meaning that the CA1 IRQ could fire before the slot line reads active). Because of this, the nubus_active flags were used to mask IRQs, which is actually worse than the problem it tries to solve. Any interrupt masked by nubus_active will remain asserted and prevent further transitions on CA1. And so the nubus gets wedged regardless of hardware (emulated VIA ASIC, real VIA chip or RBV). The best solution to this hardware limitation of genuine VIAs is to disable the umbrella SLOTS IRQ when disabling a slot on those machines. Unfortunately, this means all slot IRQs get disabled when any slot IRQ is disabled. But it is only a problem when there's more than 1 device using nubus interrupts. Another potential problem for genuine VIAs is an unregistered nubus IRQ. Eventually it will be possible to enable the CA1 interrupt by installing its handler only _after_ all nubus drivers have loaded but _before_ the kernel needs them, at which time this last problem can be fixed. For now it can be worked around: - disable MacOS extensions - don't boot MacOS (use the Emile bootloader instead) - get the bootloaders to disable ROM drivers (Penguin does this for video cards already, don't know about Emile) - physically remove unsupported cards Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-01 20:32:57 +00:00
break;
}
}
void via_nubus_irq_startup(int irq)
{
int irq_idx = IRQ_IDX(irq);
switch (macintosh_config->via_type) {
case MAC_VIA_II:
m68k: Mac nubus IRQ fixes (plan E) Some Macs lack a slot interrupt enable register. So the existing code makes disabled and unregistered slot IRQ lines outputs set high. This seems to work on quadras, but does not work on genuine VIAs (perhaps the card still succeeds in pulling the line low, or perhaps because this increases the settle time on the port A input, meaning that the CA1 IRQ could fire before the slot line reads active). Because of this, the nubus_active flags were used to mask IRQs, which is actually worse than the problem it tries to solve. Any interrupt masked by nubus_active will remain asserted and prevent further transitions on CA1. And so the nubus gets wedged regardless of hardware (emulated VIA ASIC, real VIA chip or RBV). The best solution to this hardware limitation of genuine VIAs is to disable the umbrella SLOTS IRQ when disabling a slot on those machines. Unfortunately, this means all slot IRQs get disabled when any slot IRQ is disabled. But it is only a problem when there's more than 1 device using nubus interrupts. Another potential problem for genuine VIAs is an unregistered nubus IRQ. Eventually it will be possible to enable the CA1 interrupt by installing its handler only _after_ all nubus drivers have loaded but _before_ the kernel needs them, at which time this last problem can be fixed. For now it can be worked around: - disable MacOS extensions - don't boot MacOS (use the Emile bootloader instead) - get the bootloaders to disable ROM drivers (Penguin does this for video cards already, don't know about Emile) - physically remove unsupported cards Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-01 20:32:57 +00:00
case MAC_VIA_QUADRA:
/* Make the port A line an input. Probably redundant. */
if (macintosh_config->via_type == MAC_VIA_II) {
/* The top two bits are RAM size outputs. */
via2[vDirA] &= 0xC0 | ~(1 << irq_idx);
} else {
/* Allow NuBus slots 9 through F. */
via2[vDirA] &= 0x80 | ~(1 << irq_idx);
}
/* fall through */
case MAC_VIA_IICI:
via_irq_enable(irq);
break;
}
}
void via_nubus_irq_shutdown(int irq)
{
switch (macintosh_config->via_type) {
case MAC_VIA_II:
case MAC_VIA_QUADRA:
/* Ensure that the umbrella CA1 interrupt remains enabled. */
via_irq_enable(irq);
break;
case MAC_VIA_IICI:
via_irq_disable(irq);
m68k: Mac nubus IRQ fixes (plan E) Some Macs lack a slot interrupt enable register. So the existing code makes disabled and unregistered slot IRQ lines outputs set high. This seems to work on quadras, but does not work on genuine VIAs (perhaps the card still succeeds in pulling the line low, or perhaps because this increases the settle time on the port A input, meaning that the CA1 IRQ could fire before the slot line reads active). Because of this, the nubus_active flags were used to mask IRQs, which is actually worse than the problem it tries to solve. Any interrupt masked by nubus_active will remain asserted and prevent further transitions on CA1. And so the nubus gets wedged regardless of hardware (emulated VIA ASIC, real VIA chip or RBV). The best solution to this hardware limitation of genuine VIAs is to disable the umbrella SLOTS IRQ when disabling a slot on those machines. Unfortunately, this means all slot IRQs get disabled when any slot IRQ is disabled. But it is only a problem when there's more than 1 device using nubus interrupts. Another potential problem for genuine VIAs is an unregistered nubus IRQ. Eventually it will be possible to enable the CA1 interrupt by installing its handler only _after_ all nubus drivers have loaded but _before_ the kernel needs them, at which time this last problem can be fixed. For now it can be worked around: - disable MacOS extensions - don't boot MacOS (use the Emile bootloader instead) - get the bootloaders to disable ROM drivers (Penguin does this for video cards already, don't know about Emile) - physically remove unsupported cards Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-01 20:32:57 +00:00
break;
}
}
/*
* The generic VIA interrupt routines (shamelessly stolen from Alan Cox's
* via6522.c :-), disable/pending masks added.
*/
#define VIA_TIMER_1_INT BIT(6)
void via1_irq(struct irq_desc *desc)
{
int irq_num;
unsigned char irq_bit, events;
events = via1[vIFR] & via1[vIER] & 0x7F;
if (!events)
return;
irq_num = IRQ_MAC_TIMER_1;
irq_bit = VIA_TIMER_1_INT;
if (events & irq_bit) {
unsigned long flags;
local_irq_save(flags);
via1[vIFR] = irq_bit;
generic_handle_irq(irq_num);
local_irq_restore(flags);
events &= ~irq_bit;
if (!events)
return;
}
irq_num = VIA1_SOURCE_BASE;
irq_bit = 1;
do {
if (events & irq_bit) {
via1[vIFR] = irq_bit;
generic_handle_irq(irq_num);
}
++irq_num;
irq_bit <<= 1;
} while (events >= irq_bit);
}
static void via2_irq(struct irq_desc *desc)
{
int irq_num;
unsigned char irq_bit, events;
events = via2[gIFR] & via2[gIER] & 0x7F;
if (!events)
return;
irq_num = VIA2_SOURCE_BASE;
irq_bit = 1;
do {
if (events & irq_bit) {
via2[gIFR] = irq_bit | rbv_clear;
generic_handle_irq(irq_num);
}
++irq_num;
irq_bit <<= 1;
} while (events >= irq_bit);
}
/*
* Dispatch Nubus interrupts. We are called as a secondary dispatch by the
* VIA2 dispatcher as a fast interrupt handler.
*/
static void via_nubus_irq(struct irq_desc *desc)
{
int slot_irq;
unsigned char slot_bit, events;
events = ~via2[gBufA] & 0x7F;
if (rbv_present)
events &= via2[rSIER];
else
events &= ~via2[vDirA];
if (!events)
return;
do {
slot_irq = IRQ_NUBUS_F;
slot_bit = 0x40;
do {
if (events & slot_bit) {
events &= ~slot_bit;
generic_handle_irq(slot_irq);
}
--slot_irq;
slot_bit >>= 1;
} while (events);
/* clear the CA1 interrupt and make certain there's no more. */
via2[gIFR] = 0x02 | rbv_clear;
events = ~via2[gBufA] & 0x7F;
if (rbv_present)
events &= via2[rSIER];
else
events &= ~via2[vDirA];
} while (events);
}
/*
* Register the interrupt dispatchers for VIA or RBV machines only.
*/
void __init via_register_interrupts(void)
{
if (via_alt_mapping) {
/* software interrupt */
irq_set_chained_handler(IRQ_AUTO_1, via1_irq);
/* via1 interrupt */
irq_set_chained_handler(IRQ_AUTO_6, via1_irq);
} else {
irq_set_chained_handler(IRQ_AUTO_1, via1_irq);
}
irq_set_chained_handler(IRQ_AUTO_2, via2_irq);
irq_set_chained_handler(IRQ_MAC_NUBUS, via_nubus_irq);
}
void via_irq_enable(int irq) {
int irq_src = IRQ_SRC(irq);
int irq_idx = IRQ_IDX(irq);
if (irq_src == 1) {
m68k: Mac nubus IRQ fixes (plan E) Some Macs lack a slot interrupt enable register. So the existing code makes disabled and unregistered slot IRQ lines outputs set high. This seems to work on quadras, but does not work on genuine VIAs (perhaps the card still succeeds in pulling the line low, or perhaps because this increases the settle time on the port A input, meaning that the CA1 IRQ could fire before the slot line reads active). Because of this, the nubus_active flags were used to mask IRQs, which is actually worse than the problem it tries to solve. Any interrupt masked by nubus_active will remain asserted and prevent further transitions on CA1. And so the nubus gets wedged regardless of hardware (emulated VIA ASIC, real VIA chip or RBV). The best solution to this hardware limitation of genuine VIAs is to disable the umbrella SLOTS IRQ when disabling a slot on those machines. Unfortunately, this means all slot IRQs get disabled when any slot IRQ is disabled. But it is only a problem when there's more than 1 device using nubus interrupts. Another potential problem for genuine VIAs is an unregistered nubus IRQ. Eventually it will be possible to enable the CA1 interrupt by installing its handler only _after_ all nubus drivers have loaded but _before_ the kernel needs them, at which time this last problem can be fixed. For now it can be worked around: - disable MacOS extensions - don't boot MacOS (use the Emile bootloader instead) - get the bootloaders to disable ROM drivers (Penguin does this for video cards already, don't know about Emile) - physically remove unsupported cards Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-01 20:32:57 +00:00
via1[vIER] = IER_SET_BIT(irq_idx);
} else if (irq_src == 2) {
m68k: Mac nubus IRQ fixes (plan E) Some Macs lack a slot interrupt enable register. So the existing code makes disabled and unregistered slot IRQ lines outputs set high. This seems to work on quadras, but does not work on genuine VIAs (perhaps the card still succeeds in pulling the line low, or perhaps because this increases the settle time on the port A input, meaning that the CA1 IRQ could fire before the slot line reads active). Because of this, the nubus_active flags were used to mask IRQs, which is actually worse than the problem it tries to solve. Any interrupt masked by nubus_active will remain asserted and prevent further transitions on CA1. And so the nubus gets wedged regardless of hardware (emulated VIA ASIC, real VIA chip or RBV). The best solution to this hardware limitation of genuine VIAs is to disable the umbrella SLOTS IRQ when disabling a slot on those machines. Unfortunately, this means all slot IRQs get disabled when any slot IRQ is disabled. But it is only a problem when there's more than 1 device using nubus interrupts. Another potential problem for genuine VIAs is an unregistered nubus IRQ. Eventually it will be possible to enable the CA1 interrupt by installing its handler only _after_ all nubus drivers have loaded but _before_ the kernel needs them, at which time this last problem can be fixed. For now it can be worked around: - disable MacOS extensions - don't boot MacOS (use the Emile bootloader instead) - get the bootloaders to disable ROM drivers (Penguin does this for video cards already, don't know about Emile) - physically remove unsupported cards Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-01 20:32:57 +00:00
if (irq != IRQ_MAC_NUBUS || nubus_disabled == 0)
via2[gIER] = IER_SET_BIT(irq_idx);
} else if (irq_src == 7) {
m68k: Mac nubus IRQ fixes (plan E) Some Macs lack a slot interrupt enable register. So the existing code makes disabled and unregistered slot IRQ lines outputs set high. This seems to work on quadras, but does not work on genuine VIAs (perhaps the card still succeeds in pulling the line low, or perhaps because this increases the settle time on the port A input, meaning that the CA1 IRQ could fire before the slot line reads active). Because of this, the nubus_active flags were used to mask IRQs, which is actually worse than the problem it tries to solve. Any interrupt masked by nubus_active will remain asserted and prevent further transitions on CA1. And so the nubus gets wedged regardless of hardware (emulated VIA ASIC, real VIA chip or RBV). The best solution to this hardware limitation of genuine VIAs is to disable the umbrella SLOTS IRQ when disabling a slot on those machines. Unfortunately, this means all slot IRQs get disabled when any slot IRQ is disabled. But it is only a problem when there's more than 1 device using nubus interrupts. Another potential problem for genuine VIAs is an unregistered nubus IRQ. Eventually it will be possible to enable the CA1 interrupt by installing its handler only _after_ all nubus drivers have loaded but _before_ the kernel needs them, at which time this last problem can be fixed. For now it can be worked around: - disable MacOS extensions - don't boot MacOS (use the Emile bootloader instead) - get the bootloaders to disable ROM drivers (Penguin does this for video cards already, don't know about Emile) - physically remove unsupported cards Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-01 20:32:57 +00:00
switch (macintosh_config->via_type) {
case MAC_VIA_II:
case MAC_VIA_QUADRA:
m68k: Mac nubus IRQ fixes (plan E) Some Macs lack a slot interrupt enable register. So the existing code makes disabled and unregistered slot IRQ lines outputs set high. This seems to work on quadras, but does not work on genuine VIAs (perhaps the card still succeeds in pulling the line low, or perhaps because this increases the settle time on the port A input, meaning that the CA1 IRQ could fire before the slot line reads active). Because of this, the nubus_active flags were used to mask IRQs, which is actually worse than the problem it tries to solve. Any interrupt masked by nubus_active will remain asserted and prevent further transitions on CA1. And so the nubus gets wedged regardless of hardware (emulated VIA ASIC, real VIA chip or RBV). The best solution to this hardware limitation of genuine VIAs is to disable the umbrella SLOTS IRQ when disabling a slot on those machines. Unfortunately, this means all slot IRQs get disabled when any slot IRQ is disabled. But it is only a problem when there's more than 1 device using nubus interrupts. Another potential problem for genuine VIAs is an unregistered nubus IRQ. Eventually it will be possible to enable the CA1 interrupt by installing its handler only _after_ all nubus drivers have loaded but _before_ the kernel needs them, at which time this last problem can be fixed. For now it can be worked around: - disable MacOS extensions - don't boot MacOS (use the Emile bootloader instead) - get the bootloaders to disable ROM drivers (Penguin does this for video cards already, don't know about Emile) - physically remove unsupported cards Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-01 20:32:57 +00:00
nubus_disabled &= ~(1 << irq_idx);
/* Enable the CA1 interrupt when no slot is disabled. */
if (!nubus_disabled)
via2[gIER] = IER_SET_BIT(1);
break;
case MAC_VIA_IICI:
m68k: Mac nubus IRQ fixes (plan E) Some Macs lack a slot interrupt enable register. So the existing code makes disabled and unregistered slot IRQ lines outputs set high. This seems to work on quadras, but does not work on genuine VIAs (perhaps the card still succeeds in pulling the line low, or perhaps because this increases the settle time on the port A input, meaning that the CA1 IRQ could fire before the slot line reads active). Because of this, the nubus_active flags were used to mask IRQs, which is actually worse than the problem it tries to solve. Any interrupt masked by nubus_active will remain asserted and prevent further transitions on CA1. And so the nubus gets wedged regardless of hardware (emulated VIA ASIC, real VIA chip or RBV). The best solution to this hardware limitation of genuine VIAs is to disable the umbrella SLOTS IRQ when disabling a slot on those machines. Unfortunately, this means all slot IRQs get disabled when any slot IRQ is disabled. But it is only a problem when there's more than 1 device using nubus interrupts. Another potential problem for genuine VIAs is an unregistered nubus IRQ. Eventually it will be possible to enable the CA1 interrupt by installing its handler only _after_ all nubus drivers have loaded but _before_ the kernel needs them, at which time this last problem can be fixed. For now it can be worked around: - disable MacOS extensions - don't boot MacOS (use the Emile bootloader instead) - get the bootloaders to disable ROM drivers (Penguin does this for video cards already, don't know about Emile) - physically remove unsupported cards Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-01 20:32:57 +00:00
/* On RBV, enable the slot interrupt.
* SIER works like IER.
*/
via2[rSIER] = IER_SET_BIT(irq_idx);
m68k: Mac nubus IRQ fixes (plan E) Some Macs lack a slot interrupt enable register. So the existing code makes disabled and unregistered slot IRQ lines outputs set high. This seems to work on quadras, but does not work on genuine VIAs (perhaps the card still succeeds in pulling the line low, or perhaps because this increases the settle time on the port A input, meaning that the CA1 IRQ could fire before the slot line reads active). Because of this, the nubus_active flags were used to mask IRQs, which is actually worse than the problem it tries to solve. Any interrupt masked by nubus_active will remain asserted and prevent further transitions on CA1. And so the nubus gets wedged regardless of hardware (emulated VIA ASIC, real VIA chip or RBV). The best solution to this hardware limitation of genuine VIAs is to disable the umbrella SLOTS IRQ when disabling a slot on those machines. Unfortunately, this means all slot IRQs get disabled when any slot IRQ is disabled. But it is only a problem when there's more than 1 device using nubus interrupts. Another potential problem for genuine VIAs is an unregistered nubus IRQ. Eventually it will be possible to enable the CA1 interrupt by installing its handler only _after_ all nubus drivers have loaded but _before_ the kernel needs them, at which time this last problem can be fixed. For now it can be worked around: - disable MacOS extensions - don't boot MacOS (use the Emile bootloader instead) - get the bootloaders to disable ROM drivers (Penguin does this for video cards already, don't know about Emile) - physically remove unsupported cards Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-01 20:32:57 +00:00
break;
}
}
}
void via_irq_disable(int irq) {
int irq_src = IRQ_SRC(irq);
int irq_idx = IRQ_IDX(irq);
if (irq_src == 1) {
m68k: Mac nubus IRQ fixes (plan E) Some Macs lack a slot interrupt enable register. So the existing code makes disabled and unregistered slot IRQ lines outputs set high. This seems to work on quadras, but does not work on genuine VIAs (perhaps the card still succeeds in pulling the line low, or perhaps because this increases the settle time on the port A input, meaning that the CA1 IRQ could fire before the slot line reads active). Because of this, the nubus_active flags were used to mask IRQs, which is actually worse than the problem it tries to solve. Any interrupt masked by nubus_active will remain asserted and prevent further transitions on CA1. And so the nubus gets wedged regardless of hardware (emulated VIA ASIC, real VIA chip or RBV). The best solution to this hardware limitation of genuine VIAs is to disable the umbrella SLOTS IRQ when disabling a slot on those machines. Unfortunately, this means all slot IRQs get disabled when any slot IRQ is disabled. But it is only a problem when there's more than 1 device using nubus interrupts. Another potential problem for genuine VIAs is an unregistered nubus IRQ. Eventually it will be possible to enable the CA1 interrupt by installing its handler only _after_ all nubus drivers have loaded but _before_ the kernel needs them, at which time this last problem can be fixed. For now it can be worked around: - disable MacOS extensions - don't boot MacOS (use the Emile bootloader instead) - get the bootloaders to disable ROM drivers (Penguin does this for video cards already, don't know about Emile) - physically remove unsupported cards Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-01 20:32:57 +00:00
via1[vIER] = IER_CLR_BIT(irq_idx);
} else if (irq_src == 2) {
m68k: Mac nubus IRQ fixes (plan E) Some Macs lack a slot interrupt enable register. So the existing code makes disabled and unregistered slot IRQ lines outputs set high. This seems to work on quadras, but does not work on genuine VIAs (perhaps the card still succeeds in pulling the line low, or perhaps because this increases the settle time on the port A input, meaning that the CA1 IRQ could fire before the slot line reads active). Because of this, the nubus_active flags were used to mask IRQs, which is actually worse than the problem it tries to solve. Any interrupt masked by nubus_active will remain asserted and prevent further transitions on CA1. And so the nubus gets wedged regardless of hardware (emulated VIA ASIC, real VIA chip or RBV). The best solution to this hardware limitation of genuine VIAs is to disable the umbrella SLOTS IRQ when disabling a slot on those machines. Unfortunately, this means all slot IRQs get disabled when any slot IRQ is disabled. But it is only a problem when there's more than 1 device using nubus interrupts. Another potential problem for genuine VIAs is an unregistered nubus IRQ. Eventually it will be possible to enable the CA1 interrupt by installing its handler only _after_ all nubus drivers have loaded but _before_ the kernel needs them, at which time this last problem can be fixed. For now it can be worked around: - disable MacOS extensions - don't boot MacOS (use the Emile bootloader instead) - get the bootloaders to disable ROM drivers (Penguin does this for video cards already, don't know about Emile) - physically remove unsupported cards Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-01 20:32:57 +00:00
via2[gIER] = IER_CLR_BIT(irq_idx);
} else if (irq_src == 7) {
m68k: Mac nubus IRQ fixes (plan E) Some Macs lack a slot interrupt enable register. So the existing code makes disabled and unregistered slot IRQ lines outputs set high. This seems to work on quadras, but does not work on genuine VIAs (perhaps the card still succeeds in pulling the line low, or perhaps because this increases the settle time on the port A input, meaning that the CA1 IRQ could fire before the slot line reads active). Because of this, the nubus_active flags were used to mask IRQs, which is actually worse than the problem it tries to solve. Any interrupt masked by nubus_active will remain asserted and prevent further transitions on CA1. And so the nubus gets wedged regardless of hardware (emulated VIA ASIC, real VIA chip or RBV). The best solution to this hardware limitation of genuine VIAs is to disable the umbrella SLOTS IRQ when disabling a slot on those machines. Unfortunately, this means all slot IRQs get disabled when any slot IRQ is disabled. But it is only a problem when there's more than 1 device using nubus interrupts. Another potential problem for genuine VIAs is an unregistered nubus IRQ. Eventually it will be possible to enable the CA1 interrupt by installing its handler only _after_ all nubus drivers have loaded but _before_ the kernel needs them, at which time this last problem can be fixed. For now it can be worked around: - disable MacOS extensions - don't boot MacOS (use the Emile bootloader instead) - get the bootloaders to disable ROM drivers (Penguin does this for video cards already, don't know about Emile) - physically remove unsupported cards Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-01 20:32:57 +00:00
switch (macintosh_config->via_type) {
case MAC_VIA_II:
case MAC_VIA_QUADRA:
m68k: Mac nubus IRQ fixes (plan E) Some Macs lack a slot interrupt enable register. So the existing code makes disabled and unregistered slot IRQ lines outputs set high. This seems to work on quadras, but does not work on genuine VIAs (perhaps the card still succeeds in pulling the line low, or perhaps because this increases the settle time on the port A input, meaning that the CA1 IRQ could fire before the slot line reads active). Because of this, the nubus_active flags were used to mask IRQs, which is actually worse than the problem it tries to solve. Any interrupt masked by nubus_active will remain asserted and prevent further transitions on CA1. And so the nubus gets wedged regardless of hardware (emulated VIA ASIC, real VIA chip or RBV). The best solution to this hardware limitation of genuine VIAs is to disable the umbrella SLOTS IRQ when disabling a slot on those machines. Unfortunately, this means all slot IRQs get disabled when any slot IRQ is disabled. But it is only a problem when there's more than 1 device using nubus interrupts. Another potential problem for genuine VIAs is an unregistered nubus IRQ. Eventually it will be possible to enable the CA1 interrupt by installing its handler only _after_ all nubus drivers have loaded but _before_ the kernel needs them, at which time this last problem can be fixed. For now it can be worked around: - disable MacOS extensions - don't boot MacOS (use the Emile bootloader instead) - get the bootloaders to disable ROM drivers (Penguin does this for video cards already, don't know about Emile) - physically remove unsupported cards Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-01 20:32:57 +00:00
nubus_disabled |= 1 << irq_idx;
if (nubus_disabled)
via2[gIER] = IER_CLR_BIT(1);
break;
case MAC_VIA_IICI:
via2[rSIER] = IER_CLR_BIT(irq_idx);
m68k: Mac nubus IRQ fixes (plan E) Some Macs lack a slot interrupt enable register. So the existing code makes disabled and unregistered slot IRQ lines outputs set high. This seems to work on quadras, but does not work on genuine VIAs (perhaps the card still succeeds in pulling the line low, or perhaps because this increases the settle time on the port A input, meaning that the CA1 IRQ could fire before the slot line reads active). Because of this, the nubus_active flags were used to mask IRQs, which is actually worse than the problem it tries to solve. Any interrupt masked by nubus_active will remain asserted and prevent further transitions on CA1. And so the nubus gets wedged regardless of hardware (emulated VIA ASIC, real VIA chip or RBV). The best solution to this hardware limitation of genuine VIAs is to disable the umbrella SLOTS IRQ when disabling a slot on those machines. Unfortunately, this means all slot IRQs get disabled when any slot IRQ is disabled. But it is only a problem when there's more than 1 device using nubus interrupts. Another potential problem for genuine VIAs is an unregistered nubus IRQ. Eventually it will be possible to enable the CA1 interrupt by installing its handler only _after_ all nubus drivers have loaded but _before_ the kernel needs them, at which time this last problem can be fixed. For now it can be worked around: - disable MacOS extensions - don't boot MacOS (use the Emile bootloader instead) - get the bootloaders to disable ROM drivers (Penguin does this for video cards already, don't know about Emile) - physically remove unsupported cards Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-01 20:32:57 +00:00
break;
}
}
}
void via1_set_head(int head)
{
if (head == 0)
via1[vBufA] &= ~VIA1A_vHeadSel;
else
via1[vBufA] |= VIA1A_vHeadSel;
}
EXPORT_SYMBOL(via1_set_head);
int via2_scsi_drq_pending(void)
{
return via2[gIFR] & (1 << IRQ_IDX(IRQ_MAC_SCSIDRQ));
}
EXPORT_SYMBOL(via2_scsi_drq_pending);
/* timer and clock source */
#define VIA_CLOCK_FREQ 783360 /* VIA "phase 2" clock in Hz */
#define VIA_TIMER_CYCLES (VIA_CLOCK_FREQ / HZ) /* clock cycles per jiffy */
#define VIA_TC (VIA_TIMER_CYCLES - 2) /* including 0 and -1 */
#define VIA_TC_LOW (VIA_TC & 0xFF)
#define VIA_TC_HIGH (VIA_TC >> 8)
static u64 mac_read_clk(struct clocksource *cs);
static struct clocksource mac_clk = {
.name = "via1",
.rating = 250,
.read = mac_read_clk,
.mask = CLOCKSOURCE_MASK(32),
.flags = CLOCK_SOURCE_IS_CONTINUOUS,
};
static u32 clk_total, clk_offset;
static irqreturn_t via_timer_handler(int irq, void *dev_id)
{
irq_handler_t timer_routine = dev_id;
clk_total += VIA_TIMER_CYCLES;
clk_offset = 0;
timer_routine(0, NULL);
return IRQ_HANDLED;
}
void __init via_init_clock(irq_handler_t timer_routine)
{
if (request_irq(IRQ_MAC_TIMER_1, via_timer_handler, IRQF_TIMER, "timer",
timer_routine)) {
pr_err("Couldn't register %s interrupt\n", "timer");
return;
}
via1[vT1LL] = VIA_TC_LOW;
via1[vT1LH] = VIA_TC_HIGH;
via1[vT1CL] = VIA_TC_LOW;
via1[vT1CH] = VIA_TC_HIGH;
via1[vACR] |= 0x40;
clocksource_register_hz(&mac_clk, VIA_CLOCK_FREQ);
}
static u64 mac_read_clk(struct clocksource *cs)
{
unsigned long flags;
u8 count_high;
u16 count;
u32 ticks;
/*
* Timer counter wrap-around is detected with the timer interrupt flag
* but reading the counter low byte (vT1CL) would reset the flag.
* Also, accessing both counter registers is essentially a data race.
* These problems are avoided by ignoring the low byte. Clock accuracy
* is 256 times worse (error can reach 0.327 ms) but CPU overhead is
* reduced by avoiding slow VIA register accesses.
*/
local_irq_save(flags);
count_high = via1[vT1CH];
if (count_high == 0xFF)
count_high = 0;
if (count_high > 0 && (via1[vIFR] & VIA_TIMER_1_INT))
clk_offset = VIA_TIMER_CYCLES;
count = count_high << 8;
ticks = VIA_TIMER_CYCLES - count;
ticks += clk_offset + clk_total;
local_irq_restore(flags);
return ticks;
}