sram.c
/*
* linux/arch/arm/plat-omap/sram.c
*
* OMAP SRAM detection and management
*
* Copyright (C) 2005 Nokia Corporation
* Written by Tony Lindgren <tony@atomide.com>
*
* 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/config.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <asm/mach/map.h>
#include <asm/io.h>
#include <asm/cacheflush.h>
#include <asm/arch/sram.h>
#define OMAP1_SRAM_PA 0x20000000
#define OMAP1_SRAM_VA 0xd0000000
#define OMAP2_SRAM_PA 0x40200000
#define OMAP2_SRAM_VA 0xd0000000
#define SRAM_BOOTLOADER_SZ 0x80
static unsigned long omap_sram_base;
static unsigned long omap_sram_size;
static unsigned long omap_sram_ceil;
/*
* The amount of SRAM depends on the core type.
* Note that we cannot try to test for SRAM here because writes
* to secure SRAM will hang the system. Also the SRAM is not
* yet mapped at this point.
*/
void __init omap_detect_sram(void)
{
if (!cpu_is_omap24xx())
omap_sram_base = OMAP1_SRAM_VA;
else
omap_sram_base = OMAP2_SRAM_VA;
if (cpu_is_omap730())
omap_sram_size = 0x32000; /* 200K */
else if (cpu_is_omap15xx())
omap_sram_size = 0x30000; /* 192K */
else if (cpu_is_omap1610() || cpu_is_omap1621() || cpu_is_omap1710())
omap_sram_size = 0x4000; /* 16K */
else if (cpu_is_omap1611())
omap_sram_size = 0x3e800; /* 250K */
else if (cpu_is_omap2420())
omap_sram_size = 0xa0014; /* 640K */
else {
printk(KERN_ERR "Could not detect SRAM size\n");
omap_sram_size = 0x4000;
}
omap_sram_ceil = omap_sram_base + omap_sram_size;
}
static struct map_desc omap_sram_io_desc[] __initdata = {
{ /* .length gets filled in at runtime */
.virtual = OMAP1_SRAM_VA,
.pfn = __phys_to_pfn(OMAP1_SRAM_PA),
.type = MT_DEVICE
}
};
/*
* In order to use last 2kB of SRAM on 1611b, we must round the size
* up to multiple of PAGE_SIZE. We cannot use ioremap for SRAM, as
* clock init needs SRAM early.
*/
void __init omap_map_sram(void)
{
if (omap_sram_size == 0)
return;
if (cpu_is_omap24xx()) {
omap_sram_io_desc[0].virtual = OMAP2_SRAM_VA;
omap_sram_io_desc[0].pfn = __phys_to_pfn(OMAP2_SRAM_PA);
}
omap_sram_io_desc[0].length = (omap_sram_size + PAGE_SIZE-1)/PAGE_SIZE;
omap_sram_io_desc[0].length *= PAGE_SIZE;
iotable_init(omap_sram_io_desc, ARRAY_SIZE(omap_sram_io_desc));
printk(KERN_INFO "SRAM: Mapped pa 0x%08lx to va 0x%08lx size: 0x%lx\n",
omap_sram_io_desc[0].pfn, omap_sram_io_desc[0].virtual,
omap_sram_io_desc[0].length);
/*
* Looks like we need to preserve some bootloader code at the
* beginning of SRAM for jumping to flash for reboot to work...
*/
memset((void *)omap_sram_base + SRAM_BOOTLOADER_SZ, 0,
omap_sram_size - SRAM_BOOTLOADER_SZ);
}
void * omap_sram_push(void * start, unsigned long size)
{
if (size > (omap_sram_ceil - (omap_sram_base + SRAM_BOOTLOADER_SZ))) {
printk(KERN_ERR "Not enough space in SRAM\n");
return NULL;
}
omap_sram_ceil -= size;
omap_sram_ceil &= ~0x3;
memcpy((void *)omap_sram_ceil, start, size);
return (void *)omap_sram_ceil;
}
static void omap_sram_error(void)
{
panic("Uninitialized SRAM function\n");
}
#ifdef CONFIG_ARCH_OMAP1
static void (*_omap_sram_reprogram_clock)(u32 dpllctl, u32 ckctl);
void omap_sram_reprogram_clock(u32 dpllctl, u32 ckctl)
{
if (!_omap_sram_reprogram_clock)
omap_sram_error();
return _omap_sram_reprogram_clock(dpllctl, ckctl);
}
int __init omap1_sram_init(void)
{
_omap_sram_reprogram_clock = omap_sram_push(sram_reprogram_clock,
sram_reprogram_clock_sz);
return 0;
}
#else
#define omap1_sram_init() do {} while (0)
#endif
#ifdef CONFIG_ARCH_OMAP2
static void (*_omap2_sram_ddr_init)(u32 *slow_dll_ctrl, u32 fast_dll_ctrl,
u32 base_cs, u32 force_unlock);
void omap2_sram_ddr_init(u32 *slow_dll_ctrl, u32 fast_dll_ctrl,
u32 base_cs, u32 force_unlock)
{
if (!_omap2_sram_ddr_init)
omap_sram_error();
return _omap2_sram_ddr_init(slow_dll_ctrl, fast_dll_ctrl,
base_cs, force_unlock);
}
static void (*_omap2_sram_reprogram_sdrc)(u32 perf_level, u32 dll_val,
u32 mem_type);
void omap2_sram_reprogram_sdrc(u32 perf_level, u32 dll_val, u32 mem_type)
{
if (!_omap2_sram_reprogram_sdrc)
omap_sram_error();
return _omap2_sram_reprogram_sdrc(perf_level, dll_val, mem_type);
}
static u32 (*_omap2_set_prcm)(u32 dpll_ctrl_val, u32 sdrc_rfr_val, int bypass);
u32 omap2_set_prcm(u32 dpll_ctrl_val, u32 sdrc_rfr_val, int bypass)
{
if (!_omap2_set_prcm)
omap_sram_error();
return _omap2_set_prcm(dpll_ctrl_val, sdrc_rfr_val, bypass);
}
int __init omap2_sram_init(void)
{
_omap2_sram_ddr_init = omap_sram_push(sram_ddr_init, sram_ddr_init_sz);
_omap2_sram_reprogram_sdrc = omap_sram_push(sram_reprogram_sdrc,
sram_reprogram_sdrc_sz);
_omap2_set_prcm = omap_sram_push(sram_set_prcm, sram_set_prcm_sz);
return 0;
}
#else
#define omap2_sram_init() do {} while (0)
#endif
int __init omap_sram_init(void)
{
omap_detect_sram();
omap_map_sram();
if (!cpu_is_omap24xx())
omap1_sram_init();
else
omap2_sram_init();
return 0;
}