linux-stable/arch/powerpc/sysdev/cpm2.c
Laurent Pinchart 7b8909940a cpm2: Round the baud-rate clock divider to the nearest integer.
Instead of rounding the divider down, improve the baud-rate generators
accuracy by rounding to the nearest integer.

Signed-off-by: Laurent Pinchart <laurentp@cse-semaphore.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2009-01-28 18:16:57 -06:00

365 lines
8.4 KiB
C

/*
* General Purpose functions for the global management of the
* 8260 Communication Processor Module.
* Copyright (c) 1999-2001 Dan Malek <dan@embeddedalley.com>
* Copyright (c) 2000 MontaVista Software, Inc (source@mvista.com)
* 2.3.99 Updates
*
* 2006 (c) MontaVista Software, Inc.
* Vitaly Bordug <vbordug@ru.mvista.com>
* Merged to arch/powerpc from arch/ppc/syslib/cpm2_common.c
*
* This file is licensed under the terms of the GNU General Public License
* version 2. This program is licensed "as is" without any warranty of any
* kind, whether express or implied.
*/
/*
*
* In addition to the individual control of the communication
* channels, there are a few functions that globally affect the
* communication processor.
*
* Buffer descriptors must be allocated from the dual ported memory
* space. The allocator for that is here. When the communication
* process is reset, we reclaim the memory available. There is
* currently no deallocator for this memory.
*/
#include <linux/errno.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/param.h>
#include <linux/string.h>
#include <linux/mm.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/of.h>
#include <asm/io.h>
#include <asm/irq.h>
#include <asm/mpc8260.h>
#include <asm/page.h>
#include <asm/pgtable.h>
#include <asm/cpm2.h>
#include <asm/rheap.h>
#include <asm/fs_pd.h>
#include <sysdev/fsl_soc.h>
cpm_cpm2_t __iomem *cpmp; /* Pointer to comm processor space */
/* We allocate this here because it is used almost exclusively for
* the communication processor devices.
*/
cpm2_map_t __iomem *cpm2_immr;
#define CPM_MAP_SIZE (0x40000) /* 256k - the PQ3 reserve this amount
of space for CPM as it is larger
than on PQ2 */
void __init cpm2_reset(void)
{
#ifdef CONFIG_PPC_85xx
cpm2_immr = ioremap(CPM_MAP_ADDR, CPM_MAP_SIZE);
#else
cpm2_immr = ioremap(get_immrbase(), CPM_MAP_SIZE);
#endif
/* Reclaim the DP memory for our use.
*/
cpm_muram_init();
/* Tell everyone where the comm processor resides.
*/
cpmp = &cpm2_immr->im_cpm;
#ifndef CONFIG_PPC_EARLY_DEBUG_CPM
/* Reset the CPM.
*/
cpm_command(CPM_CR_RST, 0);
#endif
}
static DEFINE_SPINLOCK(cmd_lock);
#define MAX_CR_CMD_LOOPS 10000
int cpm_command(u32 command, u8 opcode)
{
int i, ret;
unsigned long flags;
spin_lock_irqsave(&cmd_lock, flags);
ret = 0;
out_be32(&cpmp->cp_cpcr, command | opcode | CPM_CR_FLG);
for (i = 0; i < MAX_CR_CMD_LOOPS; i++)
if ((in_be32(&cpmp->cp_cpcr) & CPM_CR_FLG) == 0)
goto out;
printk(KERN_ERR "%s(): Not able to issue CPM command\n", __func__);
ret = -EIO;
out:
spin_unlock_irqrestore(&cmd_lock, flags);
return ret;
}
EXPORT_SYMBOL(cpm_command);
/* Set a baud rate generator. This needs lots of work. There are
* eight BRGs, which can be connected to the CPM channels or output
* as clocks. The BRGs are in two different block of internal
* memory mapped space.
* The baud rate clock is the system clock divided by something.
* It was set up long ago during the initial boot phase and is
* is given to us.
* Baud rate clocks are zero-based in the driver code (as that maps
* to port numbers). Documentation uses 1-based numbering.
*/
void __cpm2_setbrg(uint brg, uint rate, uint clk, int div16, int src)
{
u32 __iomem *bp;
u32 val;
/* This is good enough to get SMCs running.....
*/
if (brg < 4) {
bp = cpm2_map_size(im_brgc1, 16);
} else {
bp = cpm2_map_size(im_brgc5, 16);
brg -= 4;
}
bp += brg;
/* Round the clock divider to the nearest integer. */
val = (((clk * 2 / rate) - 1) & ~1) | CPM_BRG_EN | src;
if (div16)
val |= CPM_BRG_DIV16;
out_be32(bp, val);
cpm2_unmap(bp);
}
EXPORT_SYMBOL(__cpm2_setbrg);
int cpm2_clk_setup(enum cpm_clk_target target, int clock, int mode)
{
int ret = 0;
int shift;
int i, bits = 0;
cpmux_t __iomem *im_cpmux;
u32 __iomem *reg;
u32 mask = 7;
u8 clk_map[][3] = {
{CPM_CLK_FCC1, CPM_BRG5, 0},
{CPM_CLK_FCC1, CPM_BRG6, 1},
{CPM_CLK_FCC1, CPM_BRG7, 2},
{CPM_CLK_FCC1, CPM_BRG8, 3},
{CPM_CLK_FCC1, CPM_CLK9, 4},
{CPM_CLK_FCC1, CPM_CLK10, 5},
{CPM_CLK_FCC1, CPM_CLK11, 6},
{CPM_CLK_FCC1, CPM_CLK12, 7},
{CPM_CLK_FCC2, CPM_BRG5, 0},
{CPM_CLK_FCC2, CPM_BRG6, 1},
{CPM_CLK_FCC2, CPM_BRG7, 2},
{CPM_CLK_FCC2, CPM_BRG8, 3},
{CPM_CLK_FCC2, CPM_CLK13, 4},
{CPM_CLK_FCC2, CPM_CLK14, 5},
{CPM_CLK_FCC2, CPM_CLK15, 6},
{CPM_CLK_FCC2, CPM_CLK16, 7},
{CPM_CLK_FCC3, CPM_BRG5, 0},
{CPM_CLK_FCC3, CPM_BRG6, 1},
{CPM_CLK_FCC3, CPM_BRG7, 2},
{CPM_CLK_FCC3, CPM_BRG8, 3},
{CPM_CLK_FCC3, CPM_CLK13, 4},
{CPM_CLK_FCC3, CPM_CLK14, 5},
{CPM_CLK_FCC3, CPM_CLK15, 6},
{CPM_CLK_FCC3, CPM_CLK16, 7},
{CPM_CLK_SCC1, CPM_BRG1, 0},
{CPM_CLK_SCC1, CPM_BRG2, 1},
{CPM_CLK_SCC1, CPM_BRG3, 2},
{CPM_CLK_SCC1, CPM_BRG4, 3},
{CPM_CLK_SCC1, CPM_CLK11, 4},
{CPM_CLK_SCC1, CPM_CLK12, 5},
{CPM_CLK_SCC1, CPM_CLK3, 6},
{CPM_CLK_SCC1, CPM_CLK4, 7},
{CPM_CLK_SCC2, CPM_BRG1, 0},
{CPM_CLK_SCC2, CPM_BRG2, 1},
{CPM_CLK_SCC2, CPM_BRG3, 2},
{CPM_CLK_SCC2, CPM_BRG4, 3},
{CPM_CLK_SCC2, CPM_CLK11, 4},
{CPM_CLK_SCC2, CPM_CLK12, 5},
{CPM_CLK_SCC2, CPM_CLK3, 6},
{CPM_CLK_SCC2, CPM_CLK4, 7},
{CPM_CLK_SCC3, CPM_BRG1, 0},
{CPM_CLK_SCC3, CPM_BRG2, 1},
{CPM_CLK_SCC3, CPM_BRG3, 2},
{CPM_CLK_SCC3, CPM_BRG4, 3},
{CPM_CLK_SCC3, CPM_CLK5, 4},
{CPM_CLK_SCC3, CPM_CLK6, 5},
{CPM_CLK_SCC3, CPM_CLK7, 6},
{CPM_CLK_SCC3, CPM_CLK8, 7},
{CPM_CLK_SCC4, CPM_BRG1, 0},
{CPM_CLK_SCC4, CPM_BRG2, 1},
{CPM_CLK_SCC4, CPM_BRG3, 2},
{CPM_CLK_SCC4, CPM_BRG4, 3},
{CPM_CLK_SCC4, CPM_CLK5, 4},
{CPM_CLK_SCC4, CPM_CLK6, 5},
{CPM_CLK_SCC4, CPM_CLK7, 6},
{CPM_CLK_SCC4, CPM_CLK8, 7},
};
im_cpmux = cpm2_map(im_cpmux);
switch (target) {
case CPM_CLK_SCC1:
reg = &im_cpmux->cmx_scr;
shift = 24;
break;
case CPM_CLK_SCC2:
reg = &im_cpmux->cmx_scr;
shift = 16;
break;
case CPM_CLK_SCC3:
reg = &im_cpmux->cmx_scr;
shift = 8;
break;
case CPM_CLK_SCC4:
reg = &im_cpmux->cmx_scr;
shift = 0;
break;
case CPM_CLK_FCC1:
reg = &im_cpmux->cmx_fcr;
shift = 24;
break;
case CPM_CLK_FCC2:
reg = &im_cpmux->cmx_fcr;
shift = 16;
break;
case CPM_CLK_FCC3:
reg = &im_cpmux->cmx_fcr;
shift = 8;
break;
default:
printk(KERN_ERR "cpm2_clock_setup: invalid clock target\n");
return -EINVAL;
}
if (mode == CPM_CLK_RX)
shift += 3;
for (i = 0; i < ARRAY_SIZE(clk_map); i++) {
if (clk_map[i][0] == target && clk_map[i][1] == clock) {
bits = clk_map[i][2];
break;
}
}
if (i == ARRAY_SIZE(clk_map))
ret = -EINVAL;
bits <<= shift;
mask <<= shift;
out_be32(reg, (in_be32(reg) & ~mask) | bits);
cpm2_unmap(im_cpmux);
return ret;
}
int cpm2_smc_clk_setup(enum cpm_clk_target target, int clock)
{
int ret = 0;
int shift;
int i, bits = 0;
cpmux_t __iomem *im_cpmux;
u8 __iomem *reg;
u8 mask = 3;
u8 clk_map[][3] = {
{CPM_CLK_SMC1, CPM_BRG1, 0},
{CPM_CLK_SMC1, CPM_BRG7, 1},
{CPM_CLK_SMC1, CPM_CLK7, 2},
{CPM_CLK_SMC1, CPM_CLK9, 3},
{CPM_CLK_SMC2, CPM_BRG2, 0},
{CPM_CLK_SMC2, CPM_BRG8, 1},
{CPM_CLK_SMC2, CPM_CLK4, 2},
{CPM_CLK_SMC2, CPM_CLK15, 3},
};
im_cpmux = cpm2_map(im_cpmux);
switch (target) {
case CPM_CLK_SMC1:
reg = &im_cpmux->cmx_smr;
mask = 3;
shift = 4;
break;
case CPM_CLK_SMC2:
reg = &im_cpmux->cmx_smr;
mask = 3;
shift = 0;
break;
default:
printk(KERN_ERR "cpm2_smc_clock_setup: invalid clock target\n");
return -EINVAL;
}
for (i = 0; i < ARRAY_SIZE(clk_map); i++) {
if (clk_map[i][0] == target && clk_map[i][1] == clock) {
bits = clk_map[i][2];
break;
}
}
if (i == ARRAY_SIZE(clk_map))
ret = -EINVAL;
bits <<= shift;
mask <<= shift;
out_8(reg, (in_8(reg) & ~mask) | bits);
cpm2_unmap(im_cpmux);
return ret;
}
struct cpm2_ioports {
u32 dir, par, sor, odr, dat;
u32 res[3];
};
void cpm2_set_pin(int port, int pin, int flags)
{
struct cpm2_ioports __iomem *iop =
(struct cpm2_ioports __iomem *)&cpm2_immr->im_ioport;
pin = 1 << (31 - pin);
if (flags & CPM_PIN_OUTPUT)
setbits32(&iop[port].dir, pin);
else
clrbits32(&iop[port].dir, pin);
if (!(flags & CPM_PIN_GPIO))
setbits32(&iop[port].par, pin);
else
clrbits32(&iop[port].par, pin);
if (flags & CPM_PIN_SECONDARY)
setbits32(&iop[port].sor, pin);
else
clrbits32(&iop[port].sor, pin);
if (flags & CPM_PIN_OPENDRAIN)
setbits32(&iop[port].odr, pin);
else
clrbits32(&iop[port].odr, pin);
}
static int cpm_init_par_io(void)
{
struct device_node *np;
for_each_compatible_node(np, NULL, "fsl,cpm2-pario-bank")
cpm2_gpiochip_add32(np);
return 0;
}
arch_initcall(cpm_init_par_io);