kernel-ark/arch/avr32/mach-at32ap/hsmc.c
Hans-Christian Egtvedt 068d9f6eb9 [AVR32] Add nwait and tdf parameters to SMC configuration
Complete the SMC configuration code by adding nwait and tdf
parameter. After this change, we support the same parameters as the
hardware.

Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
2007-04-27 13:43:27 +02:00

188 lines
4.1 KiB
C

/*
* Static Memory Controller for AT32 chips
*
* Copyright (C) 2006 Atmel Corporation
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#define DEBUG
#include <linux/clk.h>
#include <linux/err.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <asm/io.h>
#include <asm/arch/smc.h>
#include "hsmc.h"
#define NR_CHIP_SELECTS 6
struct hsmc {
void __iomem *regs;
struct clk *pclk;
struct clk *mck;
};
static struct hsmc *hsmc;
int smc_set_configuration(int cs, const struct smc_config *config)
{
unsigned long mul;
unsigned long offset;
u32 setup, pulse, cycle, mode;
if (!hsmc)
return -ENODEV;
if (cs >= NR_CHIP_SELECTS)
return -EINVAL;
/*
* cycles = x / T = x * f
* = ((x * 1000000000) * ((f * 65536) / 1000000000)) / 65536
* = ((x * 1000000000) * (((f / 10000) * 65536) / 100000)) / 65536
*/
mul = (clk_get_rate(hsmc->mck) / 10000) << 16;
mul /= 100000;
#define ns2cyc(x) ((((x) * mul) + 65535) >> 16)
setup = (HSMC_BF(NWE_SETUP, ns2cyc(config->nwe_setup))
| HSMC_BF(NCS_WR_SETUP, ns2cyc(config->ncs_write_setup))
| HSMC_BF(NRD_SETUP, ns2cyc(config->nrd_setup))
| HSMC_BF(NCS_RD_SETUP, ns2cyc(config->ncs_read_setup)));
pulse = (HSMC_BF(NWE_PULSE, ns2cyc(config->nwe_pulse))
| HSMC_BF(NCS_WR_PULSE, ns2cyc(config->ncs_write_pulse))
| HSMC_BF(NRD_PULSE, ns2cyc(config->nrd_pulse))
| HSMC_BF(NCS_RD_PULSE, ns2cyc(config->ncs_read_pulse)));
cycle = (HSMC_BF(NWE_CYCLE, ns2cyc(config->write_cycle))
| HSMC_BF(NRD_CYCLE, ns2cyc(config->read_cycle)));
switch (config->bus_width) {
case 1:
mode = HSMC_BF(DBW, HSMC_DBW_8_BITS);
break;
case 2:
mode = HSMC_BF(DBW, HSMC_DBW_16_BITS);
break;
case 4:
mode = HSMC_BF(DBW, HSMC_DBW_32_BITS);
break;
default:
return -EINVAL;
}
switch (config->nwait_mode) {
case 0:
mode |= HSMC_BF(EXNW_MODE, HSMC_EXNW_MODE_DISABLED);
break;
case 1:
mode |= HSMC_BF(EXNW_MODE, HSMC_EXNW_MODE_RESERVED);
break;
case 2:
mode |= HSMC_BF(EXNW_MODE, HSMC_EXNW_MODE_FROZEN);
break;
case 3:
mode |= HSMC_BF(EXNW_MODE, HSMC_EXNW_MODE_READY);
break;
default:
return -EINVAL;
}
if (config->tdf_cycles) {
mode |= HSMC_BF(TDF_CYCLES, config->tdf_cycles);
}
if (config->nrd_controlled)
mode |= HSMC_BIT(READ_MODE);
if (config->nwe_controlled)
mode |= HSMC_BIT(WRITE_MODE);
if (config->byte_write)
mode |= HSMC_BIT(BAT);
if (config->tdf_mode)
mode |= HSMC_BIT(TDF_MODE);
pr_debug("smc cs%d: setup/%08x pulse/%08x cycle/%08x mode/%08x\n",
cs, setup, pulse, cycle, mode);
offset = cs * 0x10;
hsmc_writel(hsmc, SETUP0 + offset, setup);
hsmc_writel(hsmc, PULSE0 + offset, pulse);
hsmc_writel(hsmc, CYCLE0 + offset, cycle);
hsmc_writel(hsmc, MODE0 + offset, mode);
hsmc_readl(hsmc, MODE0); /* I/O barrier */
return 0;
}
EXPORT_SYMBOL(smc_set_configuration);
static int hsmc_probe(struct platform_device *pdev)
{
struct resource *regs;
struct clk *pclk, *mck;
int ret;
if (hsmc)
return -EBUSY;
regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!regs)
return -ENXIO;
pclk = clk_get(&pdev->dev, "pclk");
if (IS_ERR(pclk))
return PTR_ERR(pclk);
mck = clk_get(&pdev->dev, "mck");
if (IS_ERR(mck)) {
ret = PTR_ERR(mck);
goto out_put_pclk;
}
ret = -ENOMEM;
hsmc = kzalloc(sizeof(struct hsmc), GFP_KERNEL);
if (!hsmc)
goto out_put_clocks;
clk_enable(pclk);
clk_enable(mck);
hsmc->pclk = pclk;
hsmc->mck = mck;
hsmc->regs = ioremap(regs->start, regs->end - regs->start + 1);
if (!hsmc->regs)
goto out_disable_clocks;
dev_info(&pdev->dev, "Atmel Static Memory Controller at 0x%08lx\n",
(unsigned long)regs->start);
platform_set_drvdata(pdev, hsmc);
return 0;
out_disable_clocks:
clk_disable(mck);
clk_disable(pclk);
kfree(hsmc);
out_put_clocks:
clk_put(mck);
out_put_pclk:
clk_put(pclk);
hsmc = NULL;
return ret;
}
static struct platform_driver hsmc_driver = {
.probe = hsmc_probe,
.driver = {
.name = "smc",
},
};
static int __init hsmc_init(void)
{
return platform_driver_register(&hsmc_driver);
}
arch_initcall(hsmc_init);