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ARM: OMAP5 / DRA7: PM: Set MPUSS-EMIF clock-domain static dependency 

With EMIF clock-domain put under hardware supervised control, memory
corruption and untraceable crashes are observed on OMAP5. Further
investigation revealed that there is a weakness in the PRCM on this
specific dynamic depedency.

The recommendation is to set MPUSS static dependency towards EMIF
clock-domain to avoid issues. This recommendation holds good for DRA7
family of devices as well.

Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
[rnayak@ti.com: DRA7]
Signed-off-by: Rajendra Nayak <rnayak@ti.com>
[nm@ti.com: conflict resolution, dra7]
Signed-off-by: Nishanth Menon <nm@ti.com>
Reviewed-by: Kevin Hilman <khilman@linaro.org>
Tested-by: Kevin Hilman <khilman@linaro.org>
This commit is contained in:
Santosh Shilimkar 2013-02-06 15:51:45 +05:30 committed by Nishanth Menon
parent a89726d3b4
commit d2136bce9d
1 changed files with 33 additions and 3 deletions
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36
arch/arm/mach-omap2/pm44xx.c
View File

@ -202,6 +202,32 @@ static inline int omap4_init_static_deps(void)
return ret;
}
/**
* omap5_dra7_init_static_deps - Init static clkdm dependencies on OMAP5 and
* DRA7
*
* The dynamic dependency between MPUSS -> EMIF is broken and has
* not worked as expected. The hardware recommendation is to
* enable static dependencies for these to avoid system
* lock ups or random crashes.
*/
static inline int omap5_dra7_init_static_deps(void)
{
struct clockdomain *mpuss_clkdm, *emif_clkdm;
int ret;
mpuss_clkdm = clkdm_lookup("mpu_clkdm");
emif_clkdm = clkdm_lookup("emif_clkdm");
if (!mpuss_clkdm || !emif_clkdm)
return -EINVAL;
ret = clkdm_add_wkdep(mpuss_clkdm, emif_clkdm);
if (ret)
pr_err("Failed to add MPUSS -> EMIF wakeup dependency\n");
return ret;
}
/**
* omap4_pm_init_early - Does early initialization necessary for OMAP4+ devices
*
@ -239,10 +265,14 @@ int __init omap4_pm_init(void)
goto err2;
}
if (cpu_is_omap44xx()) {
if (cpu_is_omap44xx())
ret = omap4_init_static_deps();
if (ret)
goto err2;
else if (soc_is_omap54xx() || soc_is_dra7xx())
ret = omap5_dra7_init_static_deps();
if (ret) {
pr_err("Failed to initialise static dependencies.\n");
goto err2;
}
ret = omap4_mpuss_init();