original_kernel/arch/arm/mach-omap2/gpmc.c

210 lines
4.9 KiB
C

/*
* GPMC support functions
*
* Copyright (C) 2005-2006 Nokia Corporation
*
* Author: Juha Yrjola
*
* 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.
*/
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/err.h>
#include <linux/clk.h>
#include <asm/io.h>
#include <asm/arch/gpmc.h>
#undef DEBUG
#define GPMC_BASE 0x6800a000
#define GPMC_REVISION 0x00
#define GPMC_SYSCONFIG 0x10
#define GPMC_SYSSTATUS 0x14
#define GPMC_IRQSTATUS 0x18
#define GPMC_IRQENABLE 0x1c
#define GPMC_TIMEOUT_CONTROL 0x40
#define GPMC_ERR_ADDRESS 0x44
#define GPMC_ERR_TYPE 0x48
#define GPMC_CONFIG 0x50
#define GPMC_STATUS 0x54
#define GPMC_PREFETCH_CONFIG1 0x1e0
#define GPMC_PREFETCH_CONFIG2 0x1e4
#define GPMC_PREFETCH_CONTROL 0x1e8
#define GPMC_PREFETCH_STATUS 0x1f0
#define GPMC_ECC_CONFIG 0x1f4
#define GPMC_ECC_CONTROL 0x1f8
#define GPMC_ECC_SIZE_CONFIG 0x1fc
#define GPMC_CS0 0x60
#define GPMC_CS_SIZE 0x30
static void __iomem *gpmc_base =
(void __iomem *) IO_ADDRESS(GPMC_BASE);
static void __iomem *gpmc_cs_base =
(void __iomem *) IO_ADDRESS(GPMC_BASE) + GPMC_CS0;
static struct clk *gpmc_l3_clk;
static void gpmc_write_reg(int idx, u32 val)
{
__raw_writel(val, gpmc_base + idx);
}
static u32 gpmc_read_reg(int idx)
{
return __raw_readl(gpmc_base + idx);
}
void gpmc_cs_write_reg(int cs, int idx, u32 val)
{
void __iomem *reg_addr;
reg_addr = gpmc_cs_base + (cs * GPMC_CS_SIZE) + idx;
__raw_writel(val, reg_addr);
}
u32 gpmc_cs_read_reg(int cs, int idx)
{
return __raw_readl(gpmc_cs_base + (cs * GPMC_CS_SIZE) + idx);
}
/* TODO: Add support for gpmc_fck to clock framework and use it */
static unsigned long gpmc_get_fclk_period(void)
{
/* In picoseconds */
return 1000000000 / ((clk_get_rate(gpmc_l3_clk)) / 1000);
}
unsigned int gpmc_ns_to_ticks(unsigned int time_ns)
{
unsigned long tick_ps;
/* Calculate in picosecs to yield more exact results */
tick_ps = gpmc_get_fclk_period();
return (time_ns * 1000 + tick_ps - 1) / tick_ps;
}
#ifdef DEBUG
static int set_gpmc_timing_reg(int cs, int reg, int st_bit, int end_bit,
int time, const char *name)
#else
static int set_gpmc_timing_reg(int cs, int reg, int st_bit, int end_bit,
int time)
#endif
{
u32 l;
int ticks, mask, nr_bits;
if (time == 0)
ticks = 0;
else
ticks = gpmc_ns_to_ticks(time);
nr_bits = end_bit - st_bit + 1;
if (ticks >= 1 << nr_bits)
return -1;
mask = (1 << nr_bits) - 1;
l = gpmc_cs_read_reg(cs, reg);
#ifdef DEBUG
printk(KERN_INFO "GPMC CS%d: %-10s: %d ticks, %3lu ns (was %i ticks)\n",
cs, name, ticks, gpmc_get_fclk_period() * ticks / 1000,
(l >> st_bit) & mask);
#endif
l &= ~(mask << st_bit);
l |= ticks << st_bit;
gpmc_cs_write_reg(cs, reg, l);
return 0;
}
#ifdef DEBUG
#define GPMC_SET_ONE(reg, st, end, field) \
if (set_gpmc_timing_reg(cs, (reg), (st), (end), \
t->field, #field) < 0) \
return -1
#else
#define GPMC_SET_ONE(reg, st, end, field) \
if (set_gpmc_timing_reg(cs, (reg), (st), (end), t->field) < 0) \
return -1
#endif
int gpmc_cs_calc_divider(int cs, unsigned int sync_clk)
{
int div;
u32 l;
l = sync_clk * 1000 + (gpmc_get_fclk_period() - 1);
div = l / gpmc_get_fclk_period();
if (div > 4)
return -1;
if (div < 0)
div = 1;
return div;
}
int gpmc_cs_set_timings(int cs, const struct gpmc_timings *t)
{
int div;
u32 l;
div = gpmc_cs_calc_divider(cs, t->sync_clk);
if (div < 0)
return -1;
GPMC_SET_ONE(GPMC_CS_CONFIG2, 0, 3, cs_on);
GPMC_SET_ONE(GPMC_CS_CONFIG2, 8, 12, cs_rd_off);
GPMC_SET_ONE(GPMC_CS_CONFIG2, 16, 20, cs_wr_off);
GPMC_SET_ONE(GPMC_CS_CONFIG3, 0, 3, adv_on);
GPMC_SET_ONE(GPMC_CS_CONFIG3, 8, 12, adv_rd_off);
GPMC_SET_ONE(GPMC_CS_CONFIG3, 16, 20, adv_wr_off);
GPMC_SET_ONE(GPMC_CS_CONFIG4, 0, 3, oe_on);
GPMC_SET_ONE(GPMC_CS_CONFIG4, 8, 12, oe_off);
GPMC_SET_ONE(GPMC_CS_CONFIG4, 16, 19, we_on);
GPMC_SET_ONE(GPMC_CS_CONFIG4, 24, 28, we_off);
GPMC_SET_ONE(GPMC_CS_CONFIG5, 0, 4, rd_cycle);
GPMC_SET_ONE(GPMC_CS_CONFIG5, 8, 12, wr_cycle);
GPMC_SET_ONE(GPMC_CS_CONFIG5, 16, 20, access);
GPMC_SET_ONE(GPMC_CS_CONFIG5, 24, 27, page_burst_access);
#ifdef DEBUG
printk(KERN_INFO "GPMC CS%d CLK period is %lu (div %d)\n",
cs, gpmc_get_fclk_period(), div);
#endif
l = gpmc_cs_read_reg(cs, GPMC_CS_CONFIG1);
l &= ~0x03;
l |= (div - 1);
return 0;
}
unsigned long gpmc_cs_get_base_addr(int cs)
{
return (gpmc_cs_read_reg(cs, GPMC_CS_CONFIG7) & 0x1f) << 24;
}
void __init gpmc_init(void)
{
u32 l;
gpmc_l3_clk = clk_get(NULL, "core_l3_ck");
BUG_ON(IS_ERR(gpmc_l3_clk));
l = gpmc_read_reg(GPMC_REVISION);
printk(KERN_INFO "GPMC revision %d.%d\n", (l >> 4) & 0x0f, l & 0x0f);
/* Set smart idle mode and automatic L3 clock gating */
l = gpmc_read_reg(GPMC_SYSCONFIG);
l &= 0x03 << 3;
l |= (0x02 << 3) | (1 << 0);
gpmc_write_reg(GPMC_SYSCONFIG, l);
}