You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
132 lines
3.0 KiB
132 lines
3.0 KiB
/*
|
|
* linux/arch/arm/plat-omap/sram.c
|
|
*
|
|
* OMAP SRAM detection and management
|
|
*
|
|
* Copyright (C) 2005 Nokia Corporation
|
|
* Written by Tony Lindgren <tony@atomide.com>
|
|
*
|
|
* Copyright (C) 2009-2012 Texas Instruments
|
|
* Added OMAP4/5 support - Santosh Shilimkar <santosh.shilimkar@ti.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.
|
|
*/
|
|
#undef DEBUG
|
|
|
|
#include <linux/module.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/init.h>
|
|
#include <linux/io.h>
|
|
|
|
#include <asm/fncpy.h>
|
|
#include <asm/tlb.h>
|
|
#include <asm/cacheflush.h>
|
|
#include <asm/set_memory.h>
|
|
|
|
#include <asm/mach/map.h>
|
|
|
|
#include <plat/sram.h>
|
|
|
|
#define ROUND_DOWN(value,boundary) ((value) & (~((boundary)-1)))
|
|
|
|
static void __iomem *omap_sram_base;
|
|
static unsigned long omap_sram_skip;
|
|
static unsigned long omap_sram_size;
|
|
static void __iomem *omap_sram_ceil;
|
|
|
|
/*
|
|
* Memory allocator for SRAM: calculates the new ceiling address
|
|
* for pushing a function using the fncpy API.
|
|
*
|
|
* Note that fncpy requires the returned address to be aligned
|
|
* to an 8-byte boundary.
|
|
*/
|
|
static void *omap_sram_push_address(unsigned long size)
|
|
{
|
|
unsigned long available, new_ceil = (unsigned long)omap_sram_ceil;
|
|
|
|
available = omap_sram_ceil - (omap_sram_base + omap_sram_skip);
|
|
|
|
if (size > available) {
|
|
pr_err("Not enough space in SRAM\n");
|
|
return NULL;
|
|
}
|
|
|
|
new_ceil -= size;
|
|
new_ceil = ROUND_DOWN(new_ceil, FNCPY_ALIGN);
|
|
omap_sram_ceil = IOMEM(new_ceil);
|
|
|
|
return (void *)omap_sram_ceil;
|
|
}
|
|
|
|
void *omap_sram_push(void *funcp, unsigned long size)
|
|
{
|
|
void *sram;
|
|
unsigned long base;
|
|
int pages;
|
|
void *dst = NULL;
|
|
|
|
sram = omap_sram_push_address(size);
|
|
if (!sram)
|
|
return NULL;
|
|
|
|
base = (unsigned long)sram & PAGE_MASK;
|
|
pages = PAGE_ALIGN(size) / PAGE_SIZE;
|
|
|
|
set_memory_rw(base, pages);
|
|
|
|
dst = fncpy(sram, funcp, size);
|
|
|
|
set_memory_ro(base, pages);
|
|
set_memory_x(base, pages);
|
|
|
|
return dst;
|
|
}
|
|
|
|
/*
|
|
* The SRAM context is lost during off-idle and stack
|
|
* needs to be reset.
|
|
*/
|
|
void omap_sram_reset(void)
|
|
{
|
|
omap_sram_ceil = omap_sram_base + omap_sram_size;
|
|
}
|
|
|
|
/*
|
|
* Note that we cannot use ioremap for SRAM, as clock init needs SRAM early.
|
|
*/
|
|
void __init omap_map_sram(unsigned long start, unsigned long size,
|
|
unsigned long skip, int cached)
|
|
{
|
|
unsigned long base;
|
|
int pages;
|
|
|
|
if (size == 0)
|
|
return;
|
|
|
|
start = ROUND_DOWN(start, PAGE_SIZE);
|
|
omap_sram_size = size;
|
|
omap_sram_skip = skip;
|
|
omap_sram_base = __arm_ioremap_exec(start, size, cached);
|
|
if (!omap_sram_base) {
|
|
pr_err("SRAM: Could not map\n");
|
|
return;
|
|
}
|
|
|
|
omap_sram_reset();
|
|
|
|
/*
|
|
* Looks like we need to preserve some bootloader code at the
|
|
* beginning of SRAM for jumping to flash for reboot to work...
|
|
*/
|
|
memset_io(omap_sram_base + omap_sram_skip, 0,
|
|
omap_sram_size - omap_sram_skip);
|
|
|
|
base = (unsigned long)omap_sram_base;
|
|
pages = PAGE_ALIGN(omap_sram_size) / PAGE_SIZE;
|
|
|
|
set_memory_ro(base, pages);
|
|
set_memory_x(base, pages);
|
|
}
|
|
|