linux-stable/include/linux/tc.h
Maciej W. Rozycki 3f2aa244ee
TC: Set DMA masks for devices
Fix a TURBOchannel support regression with commit 205e1b7f51
("dma-mapping: warn when there is no coherent_dma_mask") that caused
coherent DMA allocations to produce a warning such as:

defxx: v1.11 2014/07/01  Lawrence V. Stefani and others
tc1: DEFTA at MMIO addr = 0x1e900000, IRQ = 20, Hardware addr = 08-00-2b-a3-a3-29
------------[ cut here ]------------
WARNING: CPU: 0 PID: 1 at ./include/linux/dma-mapping.h:516 dfx_dev_register+0x670/0x678
Modules linked in:
CPU: 0 PID: 1 Comm: swapper Not tainted 4.19.0-rc6 #2
Stack : ffffffff8009ffc0 fffffffffffffec0 0000000000000000 ffffffff80647650
        0000000000000000 0000000000000000 ffffffff806f5f80 ffffffffffffffff
        0000000000000000 0000000000000000 0000000000000001 ffffffff8065d4e8
        98000000031b6300 ffffffff80563478 ffffffff805685b0 ffffffffffffffff
        0000000000000000 ffffffff805d6720 0000000000000204 ffffffff80388df8
        0000000000000000 0000000000000009 ffffffff8053efd0 ffffffff806657d0
        0000000000000000 ffffffff803177f8 0000000000000000 ffffffff806d0000
        9800000003078000 980000000307b9e0 000000001e900000 ffffffff80067940
        0000000000000000 ffffffff805d6720 0000000000000204 ffffffff80388df8
        ffffffff805176c0 ffffffff8004dc78 0000000000000000 ffffffff80067940
        ...
Call Trace:
[<ffffffff8004dc78>] show_stack+0xa0/0x130
[<ffffffff80067940>] __warn+0x128/0x170
---[ end trace b1d1e094f67f3bb2 ]---

This is because the TURBOchannel bus driver fails to set the coherent
DMA mask for devices enumerated.

Set the regular and coherent DMA masks for TURBOchannel devices then,
observing that the bus protocol supports a 34-bit (16GiB) DMA address
space, by interpreting the value presented in the address cycle across
the 32 `ad' lines as a 32-bit word rather than byte address[1].  The
architectural size of the TURBOchannel DMA address space exceeds the
maximum amount of RAM any actual TURBOchannel system in existence may
have, hence both masks are the same.

This removes the warning shown above.

References:

[1] "TURBOchannel Hardware Specification", EK-369AA-OD-007B, Digital
    Equipment Corporation, January 1993, Section "DMA", pp. 1-15 -- 1-17

Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Signed-off-by: Paul Burton <paul.burton@mips.com>
Patchwork: https://patchwork.linux-mips.org/patch/20835/
Fixes: 205e1b7f51 ("dma-mapping: warn when there is no coherent_dma_mask")
Cc: stable@vger.kernel.org # 4.16+
Cc: Ralf Baechle <ralf@linux-mips.org>
2018-10-11 09:16:44 -07:00

142 lines
3.5 KiB
C

/*
* Interface to the TURBOchannel related routines.
*
* Copyright (c) 1998 Harald Koerfgen
* Copyright (c) 2005 James Simmons
* Copyright (c) 2006 Maciej W. Rozycki
*
* Based on:
*
* "TURBOchannel Firmware Specification", EK-TCAAD-FS-004
*
* from Digital Equipment Corporation.
*
* This file is subject to the terms and conditions of the GNU
* General Public License. See the file "COPYING" in the main
* directory of this archive for more details.
*/
#ifndef _LINUX_TC_H
#define _LINUX_TC_H
#include <linux/compiler.h>
#include <linux/device.h>
#include <linux/ioport.h>
#include <linux/types.h>
/*
* Offsets for the ROM header locations for TURBOchannel cards.
*/
#define TC_OLDCARD 0x3c0000
#define TC_NEWCARD 0x000000
#define TC_ROM_WIDTH 0x3e0
#define TC_ROM_STRIDE 0x3e4
#define TC_ROM_SIZE 0x3e8
#define TC_SLOT_SIZE 0x3ec
#define TC_PATTERN0 0x3f0
#define TC_PATTERN1 0x3f4
#define TC_PATTERN2 0x3f8
#define TC_PATTERN3 0x3fc
#define TC_FIRM_VER 0x400
#define TC_VENDOR 0x420
#define TC_MODULE 0x440
#define TC_FIRM_TYPE 0x460
#define TC_FLAGS 0x470
#define TC_ROM_OBJECTS 0x480
/*
* Information obtained through the get_tcinfo() PROM call.
*/
struct tcinfo {
s32 revision; /* Hardware revision level. */
s32 clk_period; /* Clock period in nanoseconds. */
s32 slot_size; /* Slot size in megabytes. */
s32 io_timeout; /* I/O timeout in cycles. */
s32 dma_range; /* DMA address range in megabytes. */
s32 max_dma_burst; /* Maximum DMA burst length. */
s32 parity; /* System module supports TC parity. */
s32 reserved[4];
};
/*
* TURBOchannel bus.
*/
struct tc_bus {
struct list_head devices; /* List of devices on this bus. */
struct resource resource[2]; /* Address space routed to this bus. */
struct device dev;
char name[13];
resource_size_t slot_base;
resource_size_t ext_slot_base;
resource_size_t ext_slot_size;
int num_tcslots;
struct tcinfo info;
};
/*
* TURBOchannel device.
*/
struct tc_dev {
struct list_head node; /* Node in list of all TC devices. */
struct tc_bus *bus; /* Bus this device is on. */
struct tc_driver *driver; /* Which driver has allocated this
device. */
struct device dev; /* Generic device interface. */
struct resource resource; /* Address space of this device. */
u64 dma_mask; /* DMA addressable range. */
char vendor[9];
char name[9];
char firmware[9];
int interrupt;
int slot;
};
#define to_tc_dev(n) container_of(n, struct tc_dev, dev)
struct tc_device_id {
char vendor[9];
char name[9];
};
/*
* TURBOchannel driver.
*/
struct tc_driver {
struct list_head node;
const struct tc_device_id *id_table;
struct device_driver driver;
};
#define to_tc_driver(drv) container_of(drv, struct tc_driver, driver)
/*
* Return TURBOchannel clock frequency in Hz.
*/
static inline unsigned long tc_get_speed(struct tc_bus *tbus)
{
return 100000 * (10000 / (unsigned long)tbus->info.clk_period);
}
#ifdef CONFIG_TC
extern struct bus_type tc_bus_type;
extern int tc_register_driver(struct tc_driver *tdrv);
extern void tc_unregister_driver(struct tc_driver *tdrv);
#else /* !CONFIG_TC */
static inline int tc_register_driver(struct tc_driver *tdrv) { return 0; }
static inline void tc_unregister_driver(struct tc_driver *tdrv) { }
#endif /* CONFIG_TC */
/*
* These have to be provided by the architecture.
*/
extern int tc_preadb(u8 *valp, void __iomem *addr);
extern int tc_bus_get_info(struct tc_bus *tbus);
extern void tc_device_get_irq(struct tc_dev *tdev);
#endif /* _LINUX_TC_H */