linux/arch/arm/mach-omap2/omap4-common.c

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/*
* OMAP4 specific common source file.
*
* Copyright (C) 2010 Texas Instruments, Inc.
* Author:
* 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.
*/
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/io.h>
#include <linux/irq.h>
#include <linux/irqchip.h>
#include <linux/platform_device.h>
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>
2011-06-26 01:04:31 +00:00
#include <linux/memblock.h>
#include <linux/of_irq.h>
#include <linux/of_platform.h>
#include <linux/export.h>
#include <linux/irqchip/arm-gic.h>
#include <linux/irqchip/irq-crossbar.h>
#include <linux/of_address.h>
#include <linux/reboot.h>
#include <linux/genalloc.h>
#include <asm/hardware/cache-l2x0.h>
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>
2011-06-26 01:04:31 +00:00
#include <asm/mach/map.h>
#include <asm/memblock.h>
#include <asm/smp_twd.h>
#include "omap-wakeupgen.h"
ARM: OMAP: Split plat/hardware.h, use local soc.h for omap2+ As the plat and mach includes need to disappear for single zImage work, we need to remove plat/hardware.h. Do this by splitting plat/hardware.h into omap1 and omap2+ specific files. The old plat/hardware.h already has omap1 only defines, so it gets moved to mach/hardware.h for omap1. For omap2+, we use the local soc.h that for now just includes the related SoC headers to keep this patch more readable. Note that the local soc.h still includes plat/cpu.h that can be dealt with in later patches. Let's also include plat/serial.h from common.h for all the board-*.c files. This allows making the include files local later on without patching these files again. Note that only minimal changes are done in this patch for the drivers/watchdog/omap_wdt.c driver to keep things compiling. Further patches are needed to eventually remove cpu_is_omap usage in the drivers. Also only minimal changes are done to sound/soc/omap/* to remove the unneeded includes and to define OMAP44XX_MCPDM_L3_BASE locally so there's no need to include omap44xx.h. While at it, also sort some of the includes in the standard way. Cc: linux-watchdog@vger.kernel.org Cc: alsa-devel@alsa-project.org Cc: Peter Ujfalusi <peter.ujfalusi@ti.com> Cc: Jarkko Nikula <jarkko.nikula@bitmer.com> Cc: Liam Girdwood <lrg@ti.com> Acked-by: Wim Van Sebroeck <wim@iguana.be> Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Tony Lindgren <tony@atomide.com>
2012-08-31 17:59:07 +00:00
#include "soc.h"
#include "iomap.h"
#include "common.h"
#include "prminst44xx.h"
#include "prcm_mpu44xx.h"
#include "omap4-sar-layout.h"
#include "omap-secure.h"
#include "sram.h"
#ifdef CONFIG_CACHE_L2X0
static void __iomem *l2cache_base;
#endif
static void __iomem *sar_ram_base;
ARM: OMAP4460: Workaround for ROM bug because of CA9 r2pX GIC control register change. On OMAP4+ devices, GIC register context is lost when MPUSS hits the OSWR(Open Switch Retention). On the CPU wakeup path, ROM code gets executed and one of the steps in it is to restore the saved context of the GIC. The ROM Code GIC distributor restoration is split in two parts: CPU specific register done by each CPU and common register done by only one CPU. Below is the abstract flow. ............................................................... - MPUSS in OSWR state. - CPU0 wakes up on the event(interrupt) and start executing ROM code. [..] - CPU0 executes "GIC Restoration:" [...] - CPU0 swicthes to non-secure mode and jumps to OS resume code. [...] - CPU0 is online in OS - CPU0 enables the GIC distributor. GICD.Enable Non-secure = 1 - CPU0 wakes up CPU1 with clock-domain force wakeup method. - CPU0 continues it's execution. [..] - CPU1 wakes up and start executing ROM code. [..] - CPU1 executes "GIC Restoration:" [..] - CPU1 swicthes to non-secure mode and jumps to OS resume code. [...] - CPU1 is online in OS and start executing. [...] - GIC Restoration: /* Common routine for HS and GP devices */ { if (GICD != 1) { /* This will be true in OSWR state */ if (GIC_SAR_BACKUP_STATE == SAVED) - CPU restores GIC distributor else - reconfigure GIC distributor to boot values. GICD.Enable secure = 1 } if (GIC_SAR_BACKUP_STATE == SAVED) - CPU restore its GIC CPU interface registers if saved. else - reconfigure its GIC CPU interface registers to boot values. } ............................................................... So as mentioned in the flow, GICD != 1 condition decides how the GIC registers are handled in ROM code wakeup path from OSWR. As evident from the flow, ROM code relies on the entire GICD register value and not specific register bits. The assumption was valid till CortexA9 r1pX version since there was only one banked bit to control secure and non-secure GICD. Secure view which ROM code sees: bit 0 == Enable Non-secure Non-secure view which HLOS sees: bit 0 == Enable secure But GICD register has changed between CortexA9 r1pX and r2pX. On r2pX GICD register is composed of 2 bits. Secure view which ROM code sees: bit 1 == Enable Non-secure bit 0 == Enable secure Non-secure view which HLOS sees: bit 0 == Enable Non-secure Hence on OMAP4460(r2pX) devices, if you go through the above flow again during CPU1 wakeup, GICD == 3 and hence ROM code fails to understand the real wakeup power state and reconfigures GIC distributor to boot values. This is nasty since you loose the entire interrupt controller context in a live system. The ROM code fix done on next OMAP4 device (OMAP4470 - r2px) is to check "GICD.Enable secure != 1" for GIC restoration in OSWR wakeup path. Since ROM code can't be fixed on OMAP4460 devices, a work around needs to be implemented. As evident from the flow, as long as CPU1 sees GICD == 1 in it's wakeup path from OSWR, the issue won't happen. Below is the flow with the work-around. ............................................................... - MPUSS in OSWR state. - CPU0 wakes up on the event(interrupt) and start executing ROM code. [..] - CPU0 executes "GIC Restoration:" [..] - CPU0 swicthes to non-secure mode and jumps to OS resume code. [..] - CPU0 is online in OS. - CPU0 does GICD.Enable Non-secure = 0 - CPU0 wakes up CPU1 with clock domain force wakeup method. - CPU0 waits for GICD.Enable Non-secure = 1 - CPU0 coninues it's execution. [..] - CPU1 wakes up and start executing ROM code. [..] - CPU1 executes "GIC Restoration:" [..] - CPU1 swicthes to non-secure mode and jumps to OS resume code. [..] - CPU1 is online in OS - CPU1 does GICD.Enable Non-secure = 1 - CPU1 start executing [...] ............................................................... With this procedure, the GIC configuration done between the CPU0 wakeup and CPU1 wakeup will not be lost but during this short windows, the CPU0 will not receive interrupts. The BUG is applicable to only OMAP4460(r2pX) devices. OMAP4470 (also r2pX) is not affected by this bug because ROM code has been fixed. Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com> Signed-off-by: Tero Kristo <t-kristo@ti.com> Signed-off-by: Kevin Hilman <khilman@ti.com>
2012-10-18 09:20:05 +00:00
static void __iomem *gic_dist_base_addr;
static void __iomem *twd_base;
#define IRQ_LOCALTIMER 29
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>
2011-06-26 01:04:31 +00:00
#ifdef CONFIG_OMAP4_ERRATA_I688
/* Used to implement memory barrier on DRAM path */
#define OMAP4_DRAM_BARRIER_VA 0xfe600000
void __iomem *dram_sync, *sram_sync;
static phys_addr_t paddr;
static u32 size;
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>
2011-06-26 01:04:31 +00:00
void omap_bus_sync(void)
{
if (dram_sync && sram_sync) {
writel_relaxed(readl_relaxed(dram_sync), dram_sync);
writel_relaxed(readl_relaxed(sram_sync), sram_sync);
isb();
}
}
EXPORT_SYMBOL(omap_bus_sync);
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>
2011-06-26 01:04:31 +00:00
static int __init omap4_sram_init(void)
{
struct device_node *np;
struct gen_pool *sram_pool;
np = of_find_compatible_node(NULL, NULL, "ti,omap4-mpu");
if (!np)
pr_warn("%s:Unable to allocate sram needed to handle errata I688\n",
__func__);
sram_pool = of_get_named_gen_pool(np, "sram", 0);
if (!sram_pool)
pr_warn("%s:Unable to get sram pool needed to handle errata I688\n",
__func__);
else
sram_sync = (void *)gen_pool_alloc(sram_pool, PAGE_SIZE);
return 0;
}
omap_arch_initcall(omap4_sram_init);
/* Steal one page physical memory for barrier implementation */
int __init omap_barrier_reserve_memblock(void)
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>
2011-06-26 01:04:31 +00:00
{
size = ALIGN(PAGE_SIZE, SZ_1M);
paddr = arm_memblock_steal(size, SZ_1M);
return 0;
}
void __init omap_barriers_init(void)
{
struct map_desc dram_io_desc[1];
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>
2011-06-26 01:04:31 +00:00
dram_io_desc[0].virtual = OMAP4_DRAM_BARRIER_VA;
dram_io_desc[0].pfn = __phys_to_pfn(paddr);
dram_io_desc[0].length = size;
dram_io_desc[0].type = MT_MEMORY_RW_SO;
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>
2011-06-26 01:04:31 +00:00
iotable_init(dram_io_desc, ARRAY_SIZE(dram_io_desc));
dram_sync = (void __iomem *) dram_io_desc[0].virtual;
pr_info("OMAP4: Map 0x%08llx to 0x%08lx for dram barrier\n",
(long long) paddr, dram_io_desc[0].virtual);
}
#else
void __init omap_barriers_init(void)
{}
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>
2011-06-26 01:04:31 +00:00
#endif
ARM: OMAP4460: Workaround for ROM bug because of CA9 r2pX GIC control register change. On OMAP4+ devices, GIC register context is lost when MPUSS hits the OSWR(Open Switch Retention). On the CPU wakeup path, ROM code gets executed and one of the steps in it is to restore the saved context of the GIC. The ROM Code GIC distributor restoration is split in two parts: CPU specific register done by each CPU and common register done by only one CPU. Below is the abstract flow. ............................................................... - MPUSS in OSWR state. - CPU0 wakes up on the event(interrupt) and start executing ROM code. [..] - CPU0 executes "GIC Restoration:" [...] - CPU0 swicthes to non-secure mode and jumps to OS resume code. [...] - CPU0 is online in OS - CPU0 enables the GIC distributor. GICD.Enable Non-secure = 1 - CPU0 wakes up CPU1 with clock-domain force wakeup method. - CPU0 continues it's execution. [..] - CPU1 wakes up and start executing ROM code. [..] - CPU1 executes "GIC Restoration:" [..] - CPU1 swicthes to non-secure mode and jumps to OS resume code. [...] - CPU1 is online in OS and start executing. [...] - GIC Restoration: /* Common routine for HS and GP devices */ { if (GICD != 1) { /* This will be true in OSWR state */ if (GIC_SAR_BACKUP_STATE == SAVED) - CPU restores GIC distributor else - reconfigure GIC distributor to boot values. GICD.Enable secure = 1 } if (GIC_SAR_BACKUP_STATE == SAVED) - CPU restore its GIC CPU interface registers if saved. else - reconfigure its GIC CPU interface registers to boot values. } ............................................................... So as mentioned in the flow, GICD != 1 condition decides how the GIC registers are handled in ROM code wakeup path from OSWR. As evident from the flow, ROM code relies on the entire GICD register value and not specific register bits. The assumption was valid till CortexA9 r1pX version since there was only one banked bit to control secure and non-secure GICD. Secure view which ROM code sees: bit 0 == Enable Non-secure Non-secure view which HLOS sees: bit 0 == Enable secure But GICD register has changed between CortexA9 r1pX and r2pX. On r2pX GICD register is composed of 2 bits. Secure view which ROM code sees: bit 1 == Enable Non-secure bit 0 == Enable secure Non-secure view which HLOS sees: bit 0 == Enable Non-secure Hence on OMAP4460(r2pX) devices, if you go through the above flow again during CPU1 wakeup, GICD == 3 and hence ROM code fails to understand the real wakeup power state and reconfigures GIC distributor to boot values. This is nasty since you loose the entire interrupt controller context in a live system. The ROM code fix done on next OMAP4 device (OMAP4470 - r2px) is to check "GICD.Enable secure != 1" for GIC restoration in OSWR wakeup path. Since ROM code can't be fixed on OMAP4460 devices, a work around needs to be implemented. As evident from the flow, as long as CPU1 sees GICD == 1 in it's wakeup path from OSWR, the issue won't happen. Below is the flow with the work-around. ............................................................... - MPUSS in OSWR state. - CPU0 wakes up on the event(interrupt) and start executing ROM code. [..] - CPU0 executes "GIC Restoration:" [..] - CPU0 swicthes to non-secure mode and jumps to OS resume code. [..] - CPU0 is online in OS. - CPU0 does GICD.Enable Non-secure = 0 - CPU0 wakes up CPU1 with clock domain force wakeup method. - CPU0 waits for GICD.Enable Non-secure = 1 - CPU0 coninues it's execution. [..] - CPU1 wakes up and start executing ROM code. [..] - CPU1 executes "GIC Restoration:" [..] - CPU1 swicthes to non-secure mode and jumps to OS resume code. [..] - CPU1 is online in OS - CPU1 does GICD.Enable Non-secure = 1 - CPU1 start executing [...] ............................................................... With this procedure, the GIC configuration done between the CPU0 wakeup and CPU1 wakeup will not be lost but during this short windows, the CPU0 will not receive interrupts. The BUG is applicable to only OMAP4460(r2pX) devices. OMAP4470 (also r2pX) is not affected by this bug because ROM code has been fixed. Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com> Signed-off-by: Tero Kristo <t-kristo@ti.com> Signed-off-by: Kevin Hilman <khilman@ti.com>
2012-10-18 09:20:05 +00:00
void gic_dist_disable(void)
{
if (gic_dist_base_addr)
writel_relaxed(0x0, gic_dist_base_addr + GIC_DIST_CTRL);
ARM: OMAP4460: Workaround for ROM bug because of CA9 r2pX GIC control register change. On OMAP4+ devices, GIC register context is lost when MPUSS hits the OSWR(Open Switch Retention). On the CPU wakeup path, ROM code gets executed and one of the steps in it is to restore the saved context of the GIC. The ROM Code GIC distributor restoration is split in two parts: CPU specific register done by each CPU and common register done by only one CPU. Below is the abstract flow. ............................................................... - MPUSS in OSWR state. - CPU0 wakes up on the event(interrupt) and start executing ROM code. [..] - CPU0 executes "GIC Restoration:" [...] - CPU0 swicthes to non-secure mode and jumps to OS resume code. [...] - CPU0 is online in OS - CPU0 enables the GIC distributor. GICD.Enable Non-secure = 1 - CPU0 wakes up CPU1 with clock-domain force wakeup method. - CPU0 continues it's execution. [..] - CPU1 wakes up and start executing ROM code. [..] - CPU1 executes "GIC Restoration:" [..] - CPU1 swicthes to non-secure mode and jumps to OS resume code. [...] - CPU1 is online in OS and start executing. [...] - GIC Restoration: /* Common routine for HS and GP devices */ { if (GICD != 1) { /* This will be true in OSWR state */ if (GIC_SAR_BACKUP_STATE == SAVED) - CPU restores GIC distributor else - reconfigure GIC distributor to boot values. GICD.Enable secure = 1 } if (GIC_SAR_BACKUP_STATE == SAVED) - CPU restore its GIC CPU interface registers if saved. else - reconfigure its GIC CPU interface registers to boot values. } ............................................................... So as mentioned in the flow, GICD != 1 condition decides how the GIC registers are handled in ROM code wakeup path from OSWR. As evident from the flow, ROM code relies on the entire GICD register value and not specific register bits. The assumption was valid till CortexA9 r1pX version since there was only one banked bit to control secure and non-secure GICD. Secure view which ROM code sees: bit 0 == Enable Non-secure Non-secure view which HLOS sees: bit 0 == Enable secure But GICD register has changed between CortexA9 r1pX and r2pX. On r2pX GICD register is composed of 2 bits. Secure view which ROM code sees: bit 1 == Enable Non-secure bit 0 == Enable secure Non-secure view which HLOS sees: bit 0 == Enable Non-secure Hence on OMAP4460(r2pX) devices, if you go through the above flow again during CPU1 wakeup, GICD == 3 and hence ROM code fails to understand the real wakeup power state and reconfigures GIC distributor to boot values. This is nasty since you loose the entire interrupt controller context in a live system. The ROM code fix done on next OMAP4 device (OMAP4470 - r2px) is to check "GICD.Enable secure != 1" for GIC restoration in OSWR wakeup path. Since ROM code can't be fixed on OMAP4460 devices, a work around needs to be implemented. As evident from the flow, as long as CPU1 sees GICD == 1 in it's wakeup path from OSWR, the issue won't happen. Below is the flow with the work-around. ............................................................... - MPUSS in OSWR state. - CPU0 wakes up on the event(interrupt) and start executing ROM code. [..] - CPU0 executes "GIC Restoration:" [..] - CPU0 swicthes to non-secure mode and jumps to OS resume code. [..] - CPU0 is online in OS. - CPU0 does GICD.Enable Non-secure = 0 - CPU0 wakes up CPU1 with clock domain force wakeup method. - CPU0 waits for GICD.Enable Non-secure = 1 - CPU0 coninues it's execution. [..] - CPU1 wakes up and start executing ROM code. [..] - CPU1 executes "GIC Restoration:" [..] - CPU1 swicthes to non-secure mode and jumps to OS resume code. [..] - CPU1 is online in OS - CPU1 does GICD.Enable Non-secure = 1 - CPU1 start executing [...] ............................................................... With this procedure, the GIC configuration done between the CPU0 wakeup and CPU1 wakeup will not be lost but during this short windows, the CPU0 will not receive interrupts. The BUG is applicable to only OMAP4460(r2pX) devices. OMAP4470 (also r2pX) is not affected by this bug because ROM code has been fixed. Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com> Signed-off-by: Tero Kristo <t-kristo@ti.com> Signed-off-by: Kevin Hilman <khilman@ti.com>
2012-10-18 09:20:05 +00:00
}
void gic_dist_enable(void)
{
if (gic_dist_base_addr)
writel_relaxed(0x1, gic_dist_base_addr + GIC_DIST_CTRL);
}
bool gic_dist_disabled(void)
{
return !(readl_relaxed(gic_dist_base_addr + GIC_DIST_CTRL) & 0x1);
}
void gic_timer_retrigger(void)
{
u32 twd_int = readl_relaxed(twd_base + TWD_TIMER_INTSTAT);
u32 gic_int = readl_relaxed(gic_dist_base_addr + GIC_DIST_PENDING_SET);
u32 twd_ctrl = readl_relaxed(twd_base + TWD_TIMER_CONTROL);
if (twd_int && !(gic_int & BIT(IRQ_LOCALTIMER))) {
/*
* The local timer interrupt got lost while the distributor was
* disabled. Ack the pending interrupt, and retrigger it.
*/
pr_warn("%s: lost localtimer interrupt\n", __func__);
writel_relaxed(1, twd_base + TWD_TIMER_INTSTAT);
if (!(twd_ctrl & TWD_TIMER_CONTROL_PERIODIC)) {
writel_relaxed(1, twd_base + TWD_TIMER_COUNTER);
twd_ctrl |= TWD_TIMER_CONTROL_ENABLE;
writel_relaxed(twd_ctrl, twd_base + TWD_TIMER_CONTROL);
}
}
}
#ifdef CONFIG_CACHE_L2X0
void __iomem *omap4_get_l2cache_base(void)
{
return l2cache_base;
}
static void omap4_l2c310_write_sec(unsigned long val, unsigned reg)
{
unsigned smc_op;
switch (reg) {
case L2X0_CTRL:
smc_op = OMAP4_MON_L2X0_CTRL_INDEX;
break;
case L2X0_AUX_CTRL:
smc_op = OMAP4_MON_L2X0_AUXCTRL_INDEX;
break;
case L2X0_DEBUG_CTRL:
smc_op = OMAP4_MON_L2X0_DBG_CTRL_INDEX;
break;
case L310_PREFETCH_CTRL:
smc_op = OMAP4_MON_L2X0_PREFETCH_INDEX;
break;
case L310_POWER_CTRL:
pr_info_once("OMAP L2C310: ROM does not support power control setting\n");
return;
default:
WARN_ONCE(1, "OMAP L2C310: ignoring write to reg 0x%x\n", reg);
return;
}
omap_smc1(smc_op, val);
}
int __init omap_l2_cache_init(void)
{
u32 aux_ctrl;
/* Static mapping, never released */
l2cache_base = ioremap(OMAP44XX_L2CACHE_BASE, SZ_4K);
if (WARN_ON(!l2cache_base))
return -ENOMEM;
/* 16-way associativity, parity disabled, way size - 64KB (es2.0 +) */
aux_ctrl = L2C_AUX_CTRL_SHARED_OVERRIDE |
L310_AUX_CTRL_DATA_PREFETCH |
L310_AUX_CTRL_INSTR_PREFETCH;
outer_cache.write_sec = omap4_l2c310_write_sec;
if (of_have_populated_dt())
l2x0_of_init(aux_ctrl, 0xcf9fffff);
else
l2x0_init(l2cache_base, aux_ctrl, 0xcf9fffff);
return 0;
}
#endif
void __iomem *omap4_get_sar_ram_base(void)
{
return sar_ram_base;
}
/*
* SAR RAM used to save and restore the HW
* context in low power modes
*/
static int __init omap4_sar_ram_init(void)
{
unsigned long sar_base;
/*
* To avoid code running on other OMAPs in
* multi-omap builds
*/
if (cpu_is_omap44xx())
sar_base = OMAP44XX_SAR_RAM_BASE;
else if (soc_is_omap54xx())
sar_base = OMAP54XX_SAR_RAM_BASE;
else
return -ENOMEM;
/* Static mapping, never released */
sar_ram_base = ioremap(sar_base, SZ_16K);
if (WARN_ON(!sar_ram_base))
return -ENOMEM;
return 0;
}
omap_early_initcall(omap4_sar_ram_init);
void __init omap_gic_of_init(void)
{
struct device_node *np;
/* Extract GIC distributor and TWD bases for OMAP4460 ROM Errata WA */
if (!cpu_is_omap446x())
goto skip_errata_init;
np = of_find_compatible_node(NULL, NULL, "arm,cortex-a9-gic");
gic_dist_base_addr = of_iomap(np, 0);
WARN_ON(!gic_dist_base_addr);
np = of_find_compatible_node(NULL, NULL, "arm,cortex-a9-twd-timer");
twd_base = of_iomap(np, 0);
WARN_ON(!twd_base);
skip_errata_init:
omap_wakeupgen_init();
#ifdef CONFIG_IRQ_CROSSBAR
irqcrossbar_init();
#endif
irqchip_init();
}