linux/arch/arm/plat-omap/sram.c
Santosh Shilimkar 137d105d50 ARM: OMAP4: Fix errata i688 with MPU interconnect barriers.
On OMAP4 SOC, intecronnects has many write buffers in the async bridges
and they need to be drained before CPU enters into standby state.

Patch 'OMAP4: PM: Add CPUX OFF mode support' added CPU PM support
but OMAP errata i688 (Async Bridge Corruption) needs to be taken
care to avoid issues like system freeze, CPU deadlocks, random
crashes with register accesses, synchronisation loss on initiators
operating on both interconnect port simultaneously.

As per the errata, if a data is stalled inside asynchronous bridge
because of back pressure, it may be accepted multiple times, creating
pointer misalignment that will corrupt next transfers on that data
path until next reset of the system (No recovery procedure once
the issue is hit, the path remains consistently broken).
Async bridge can be found on path between MPU to EMIF and
MPU to L3 interconnect. This situation can happen only when the
idle is initiated by a Master Request Disconnection (which is
trigged by software when executing WFI on CPU).

The work-around for this errata needs all the initiators
connected through async bridge must ensure that data path
is properly drained before issuing WFI. This condition will be
met if one Strongly ordered access is performed to the
target right before executing the WFI. In MPU case, L3 T2ASYNC
FIFO and DDR T2ASYNC FIFO needs to be drained. IO barrier ensure
that there is no synchronisation loss on initiators operating
on both interconnect port simultaneously.

Thanks to Russell for a tip to conver assembly function to
C fuction there by reducing 40 odd lines of code from the patch.

Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: Richard Woodruff <r-woodruff2@ti.com>
Acked-by: Jean Pihet <j-pihet@ti.com>
Reviewed-by: Kevin Hilman <khilman@ti.com>
Tested-by: Vishwanath BS <vishwanath.bs@ti.com>
Signed-off-by: Kevin Hilman <khilman@ti.com>
2011-12-08 11:29:01 -08:00

386 lines
10 KiB
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>
*
* Copyright (C) 2009 Texas Instruments
* Added OMAP4 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/tlb.h>
#include <asm/cacheflush.h>
#include <asm/mach/map.h>
#include <plat/sram.h>
#include <plat/board.h>
#include <plat/cpu.h>
#include "sram.h"
/* XXX These "sideways" includes are a sign that something is wrong */
#if defined(CONFIG_ARCH_OMAP2) || defined(CONFIG_ARCH_OMAP3)
# include "../mach-omap2/prm2xxx_3xxx.h"
# include "../mach-omap2/sdrc.h"
#endif
#define OMAP1_SRAM_PA 0x20000000
#define OMAP2_SRAM_PUB_PA (OMAP2_SRAM_PA + 0xf800)
#define OMAP3_SRAM_PUB_PA (OMAP3_SRAM_PA + 0x8000)
#ifdef CONFIG_OMAP4_ERRATA_I688
#define OMAP4_SRAM_PUB_PA OMAP4_SRAM_PA
#else
#define OMAP4_SRAM_PUB_PA (OMAP4_SRAM_PA + 0x4000)
#endif
#if defined(CONFIG_ARCH_OMAP2PLUS)
#define SRAM_BOOTLOADER_SZ 0x00
#else
#define SRAM_BOOTLOADER_SZ 0x80
#endif
#define OMAP24XX_VA_REQINFOPERM0 OMAP2_L3_IO_ADDRESS(0x68005048)
#define OMAP24XX_VA_READPERM0 OMAP2_L3_IO_ADDRESS(0x68005050)
#define OMAP24XX_VA_WRITEPERM0 OMAP2_L3_IO_ADDRESS(0x68005058)
#define OMAP34XX_VA_REQINFOPERM0 OMAP2_L3_IO_ADDRESS(0x68012848)
#define OMAP34XX_VA_READPERM0 OMAP2_L3_IO_ADDRESS(0x68012850)
#define OMAP34XX_VA_WRITEPERM0 OMAP2_L3_IO_ADDRESS(0x68012858)
#define OMAP34XX_VA_ADDR_MATCH2 OMAP2_L3_IO_ADDRESS(0x68012880)
#define OMAP34XX_VA_SMS_RG_ATT0 OMAP2_L3_IO_ADDRESS(0x6C000048)
#define GP_DEVICE 0x300
#define ROUND_DOWN(value,boundary) ((value) & (~((boundary)-1)))
static unsigned long omap_sram_start;
static void __iomem *omap_sram_base;
static unsigned long omap_sram_size;
static void __iomem *omap_sram_ceil;
/*
* Depending on the target RAMFS firewall setup, the public usable amount of
* SRAM varies. The default accessible size for all device types is 2k. A GP
* device allows ARM11 but not other initiators for full size. This
* functionality seems ok until some nice security API happens.
*/
static int is_sram_locked(void)
{
if (OMAP2_DEVICE_TYPE_GP == omap_type()) {
/* RAMFW: R/W access to all initiators for all qualifier sets */
if (cpu_is_omap242x()) {
__raw_writel(0xFF, OMAP24XX_VA_REQINFOPERM0); /* all q-vects */
__raw_writel(0xCFDE, OMAP24XX_VA_READPERM0); /* all i-read */
__raw_writel(0xCFDE, OMAP24XX_VA_WRITEPERM0); /* all i-write */
}
if (cpu_is_omap34xx()) {
__raw_writel(0xFFFF, OMAP34XX_VA_REQINFOPERM0); /* all q-vects */
__raw_writel(0xFFFF, OMAP34XX_VA_READPERM0); /* all i-read */
__raw_writel(0xFFFF, OMAP34XX_VA_WRITEPERM0); /* all i-write */
__raw_writel(0x0, OMAP34XX_VA_ADDR_MATCH2);
__raw_writel(0xFFFFFFFF, OMAP34XX_VA_SMS_RG_ATT0);
}
return 0;
} else
return 1; /* assume locked with no PPA or security driver */
}
/*
* 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.
*/
static void __init omap_detect_sram(void)
{
if (cpu_class_is_omap2()) {
if (is_sram_locked()) {
if (cpu_is_omap34xx()) {
omap_sram_start = OMAP3_SRAM_PUB_PA;
if ((omap_type() == OMAP2_DEVICE_TYPE_EMU) ||
(omap_type() == OMAP2_DEVICE_TYPE_SEC)) {
omap_sram_size = 0x7000; /* 28K */
} else {
omap_sram_size = 0x8000; /* 32K */
}
} else if (cpu_is_omap44xx()) {
omap_sram_start = OMAP4_SRAM_PUB_PA;
omap_sram_size = 0xa000; /* 40K */
} else {
omap_sram_start = OMAP2_SRAM_PUB_PA;
omap_sram_size = 0x800; /* 2K */
}
} else {
if (cpu_is_omap34xx()) {
omap_sram_start = OMAP3_SRAM_PA;
omap_sram_size = 0x10000; /* 64K */
} else if (cpu_is_omap44xx()) {
omap_sram_start = OMAP4_SRAM_PA;
omap_sram_size = 0xe000; /* 56K */
} else {
omap_sram_start = OMAP2_SRAM_PA;
if (cpu_is_omap242x())
omap_sram_size = 0xa0000; /* 640K */
else if (cpu_is_omap243x())
omap_sram_size = 0x10000; /* 64K */
}
}
} else {
omap_sram_start = OMAP1_SRAM_PA;
if (cpu_is_omap7xx())
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 = SZ_256K;
else {
pr_err("Could not detect SRAM size\n");
omap_sram_size = 0x4000;
}
}
}
/*
* Note that we cannot use ioremap for SRAM, as clock init needs SRAM early.
*/
static void __init omap_map_sram(void)
{
int cached = 1;
if (omap_sram_size == 0)
return;
#ifdef CONFIG_OMAP4_ERRATA_I688
omap_sram_start += PAGE_SIZE;
omap_sram_size -= SZ_16K;
#endif
if (cpu_is_omap34xx()) {
/*
* SRAM must be marked as non-cached on OMAP3 since the
* CORE DPLL M2 divider change code (in SRAM) runs with the
* SDRAM controller disabled, and if it is marked cached,
* the ARM may attempt to write cache lines back to SDRAM
* which will cause the system to hang.
*/
cached = 0;
}
omap_sram_start = ROUND_DOWN(omap_sram_start, PAGE_SIZE);
omap_sram_base = __arm_ioremap_exec(omap_sram_start, omap_sram_size,
cached);
if (!omap_sram_base) {
pr_err("SRAM: Could not map\n");
return;
}
omap_sram_ceil = omap_sram_base + omap_sram_size;
/*
* 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);
}
/*
* 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.
*/
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 + SRAM_BOOTLOADER_SZ);
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;
}
#ifdef CONFIG_ARCH_OMAP1
static void (*_omap_sram_reprogram_clock)(u32 dpllctl, u32 ckctl);
void omap_sram_reprogram_clock(u32 dpllctl, u32 ckctl)
{
BUG_ON(!_omap_sram_reprogram_clock);
_omap_sram_reprogram_clock(dpllctl, ckctl);
}
static int __init omap1_sram_init(void)
{
_omap_sram_reprogram_clock =
omap_sram_push(omap1_sram_reprogram_clock,
omap1_sram_reprogram_clock_sz);
return 0;
}
#else
#define omap1_sram_init() do {} while (0)
#endif
#if defined(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)
{
BUG_ON(!_omap2_sram_ddr_init);
_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)
{
BUG_ON(!_omap2_sram_reprogram_sdrc);
_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)
{
BUG_ON(!_omap2_set_prcm);
return _omap2_set_prcm(dpll_ctrl_val, sdrc_rfr_val, bypass);
}
#endif
#ifdef CONFIG_SOC_OMAP2420
static int __init omap242x_sram_init(void)
{
_omap2_sram_ddr_init = omap_sram_push(omap242x_sram_ddr_init,
omap242x_sram_ddr_init_sz);
_omap2_sram_reprogram_sdrc = omap_sram_push(omap242x_sram_reprogram_sdrc,
omap242x_sram_reprogram_sdrc_sz);
_omap2_set_prcm = omap_sram_push(omap242x_sram_set_prcm,
omap242x_sram_set_prcm_sz);
return 0;
}
#else
static inline int omap242x_sram_init(void)
{
return 0;
}
#endif
#ifdef CONFIG_SOC_OMAP2430
static int __init omap243x_sram_init(void)
{
_omap2_sram_ddr_init = omap_sram_push(omap243x_sram_ddr_init,
omap243x_sram_ddr_init_sz);
_omap2_sram_reprogram_sdrc = omap_sram_push(omap243x_sram_reprogram_sdrc,
omap243x_sram_reprogram_sdrc_sz);
_omap2_set_prcm = omap_sram_push(omap243x_sram_set_prcm,
omap243x_sram_set_prcm_sz);
return 0;
}
#else
static inline int omap243x_sram_init(void)
{
return 0;
}
#endif
#ifdef CONFIG_ARCH_OMAP3
static u32 (*_omap3_sram_configure_core_dpll)(
u32 m2, u32 unlock_dll, u32 f, u32 inc,
u32 sdrc_rfr_ctrl_0, u32 sdrc_actim_ctrl_a_0,
u32 sdrc_actim_ctrl_b_0, u32 sdrc_mr_0,
u32 sdrc_rfr_ctrl_1, u32 sdrc_actim_ctrl_a_1,
u32 sdrc_actim_ctrl_b_1, u32 sdrc_mr_1);
u32 omap3_configure_core_dpll(u32 m2, u32 unlock_dll, u32 f, u32 inc,
u32 sdrc_rfr_ctrl_0, u32 sdrc_actim_ctrl_a_0,
u32 sdrc_actim_ctrl_b_0, u32 sdrc_mr_0,
u32 sdrc_rfr_ctrl_1, u32 sdrc_actim_ctrl_a_1,
u32 sdrc_actim_ctrl_b_1, u32 sdrc_mr_1)
{
BUG_ON(!_omap3_sram_configure_core_dpll);
return _omap3_sram_configure_core_dpll(
m2, unlock_dll, f, inc,
sdrc_rfr_ctrl_0, sdrc_actim_ctrl_a_0,
sdrc_actim_ctrl_b_0, sdrc_mr_0,
sdrc_rfr_ctrl_1, sdrc_actim_ctrl_a_1,
sdrc_actim_ctrl_b_1, sdrc_mr_1);
}
#ifdef CONFIG_PM
void omap3_sram_restore_context(void)
{
omap_sram_ceil = omap_sram_base + omap_sram_size;
_omap3_sram_configure_core_dpll =
omap_sram_push(omap3_sram_configure_core_dpll,
omap3_sram_configure_core_dpll_sz);
omap_push_sram_idle();
}
#endif /* CONFIG_PM */
#endif /* CONFIG_ARCH_OMAP3 */
static inline int omap34xx_sram_init(void)
{
#if defined(CONFIG_ARCH_OMAP3) && defined(CONFIG_PM)
omap3_sram_restore_context();
#endif
return 0;
}
int __init omap_sram_init(void)
{
omap_detect_sram();
omap_map_sram();
if (!(cpu_class_is_omap2()))
omap1_sram_init();
else if (cpu_is_omap242x())
omap242x_sram_init();
else if (cpu_is_omap2430())
omap243x_sram_init();
else if (cpu_is_omap34xx())
omap34xx_sram_init();
return 0;
}