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>
The new fncpy API is better suited* for copying some
code to SRAM at runtime. This patch changes the ad-hoc
code to the more generic fncpy API.
*: 1. fncpy ensures that the thumb mode bit is propagated,
2. fncpy provides the security of type safety between the
original function and the sram function pointer.
Tested OK on OMAP3 in low power modes (RET/OFF)
using omap2plus_defconfig with !CONFIG_THUMB2_KERNEL.
Compile tested on OMAP1/2 using omap1_defconfig.
Boot tested on OMAP1 & OMAP2
Tested OK with suspend/resume on OMAP2420/n810
Boots fine on osk5912 and n800
Signed-off-by: Jean Pihet <j-pihet@ti.com>
Acked-by: Kevin Hilman <khilman@ti.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Reviewed-by: Dave Martin <dave.martin@linaro.org>
Tested-by: Kevin Hilman <khilman@ti.com>
Tested-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The SRAM PA addresses are locally defined and used at
different places, i.e. SRAM management code and idle sleep code.
The macros are now defined at a centralized place, for
easier maintenance.
Tested on N900 and Beagleboard with full RET and OFF modes,
using cpuidle and suspend.
Signed-off-by: Jean Pihet <j-pihet@ti.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Tested-by: Nishanth Menon<nm@ti.com>
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
This patch fixes sparse warnings due non declarations of static functions.
arch/arm/plat-omap/sram.c:130:13: warning: symbol 'omap_detect_sram' was not declared. Should it be static?
arch/arm/plat-omap/sram.c:216:13: warning: symbol 'omap_map_sram' was not declared. Should it be static?
arch/arm/plat-omap/sram.c:450:12: warning: symbol 'omap_sram_init' was not declared. Should it be static?
arch/arm/plat-omap/sram.c:348:12: warning: symbol 'omap242x_sram_init' was not declared. Should it be static?
arch/arm/plat-omap/sram.c:369:12: warning: symbol 'omap243x_sram_init' was not declared. Should it be static?
arch/arm/plat-omap/sram.c:425:12: warning: symbol 'omap34xx_sram_init' was not declared. Should it be static?
arch/arm/plat-omap/sram.c:441:12: warning: symbol 'omap44xx_sram_init' was not declared. Should it be static
arch/arm/plat-omap/mcbsp.c:36:6: warning: symbol 'omap_mcbsp_write' was not declared. Should it be static?
arch/arm/plat-omap/mcbsp.c:50:5: warning: symbol 'omap_mcbsp_read' was not declared. Should it be static?
arch/arm/plat-omap/mcbsp.c:65:6: warning: symbol 'omap_mcbsp_st_write' was not declared. Should it be static?
arch/arm/plat-omap/mcbsp.c:70:5: warning: symbol 'omap_mcbsp_st_read' was not declared. Should it be static?
arch/arm/plat-omap/mcbsp.c:1648:15: warning: symbol 'omap_st_add' was not declared. Should it be static?
arch/arm/plat-omap/fb.c:414:15: warning: symbol 'omapfb_reserve_sram' was not declared. Should it be static?
arch/arm/plat-omap/cpu-omap.c:43:5: warning: symbol 'omap_verify_speed' was not declared. Should it be static?
arch/arm/plat-omap/cpu-omap.c:61:14: warning: symbol 'omap_getspeed' was not declared. Should it be static?
Signed-off-by: Manjunath Kondaiah G <manjugk@ti.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: Nishanth Menon <nm@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Add context save and restore for CORE powerdomain resources in order
to support off-mode.
Signed-off-by: Rajendra Nayak <rnayak@ti.com>
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
Generalize the copy of SRAM functions into omap_push_sram_idle()
so it can be used on init but also after off-mode transitions.
Signed-off-by: Rajendra Nayak <rnayak@ti.com>
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
Move the remaining headers under plat-omap/include/mach
to plat-omap/include/plat. Also search and replace the
files using these headers to include using the right path.
This was done with:
#!/bin/bash
mach_dir_old="arch/arm/plat-omap/include/mach"
plat_dir_new="arch/arm/plat-omap/include/plat"
headers=$(cd $mach_dir_old && ls *.h)
omap_dirs="arch/arm/*omap*/ \
drivers/video/omap \
sound/soc/omap"
other_files="drivers/leds/leds-ams-delta.c \
drivers/mfd/menelaus.c \
drivers/mfd/twl4030-core.c \
drivers/mtd/nand/ams-delta.c"
for header in $headers; do
old="#include <mach\/$header"
new="#include <plat\/$header"
for dir in $omap_dirs; do
find $dir -type f -name \*.[chS] | \
xargs sed -i "s/$old/$new/"
done
find drivers/ -type f -name \*omap*.[chS] | \
xargs sed -i "s/$old/$new/"
for file in $other_files; do
sed -i "s/$old/$new/" $file
done
done
for header in $(ls $mach_dir_old/*.h); do
git mv $header $plat_dir_new/
done
Signed-off-by: Tony Lindgren <tony@atomide.com>
Santosh Shilimkar