Santosh Shilimkar <santosh.shilimkar@xxxxxx> writes:
> In addition to the standard power-management technique, the OMAP5
> MPU subsystem also employs an SR3-APG (mercury) power management
> technology to reduce leakage.
>
> It allows for full logic and memories retention on MPU_C0 and MPU_C1 and
> is controlled by the PRCM_MPU.
>
> Acked-by: Nishanth Menon <nm@xxxxxx>
> Signed-off-by: Santosh Shilimkar <santosh.shilimkar@xxxxxx>
> ---
> arch/arm/mach-omap2/omap-mpuss-lowpower.c | 27 +++++++++++++++++++++++++++
> 1 file changed, 27 insertions(+)
>
> diff --git a/arch/arm/mach-omap2/omap-mpuss-lowpower.c b/arch/arm/mach-omap2/omap-mpuss-lowpower.c
> index b1441b1..d390d18 100644
> --- a/arch/arm/mach-omap2/omap-mpuss-lowpower.c
> +++ b/arch/arm/mach-omap2/omap-mpuss-lowpower.c
> @@ -62,6 +62,10 @@
> #include "prm44xx.h"
> #include "prm-regbits-44xx.h"
>
> +/* Add defines needed for mercury mode. Refer MPU's PRM_PSCON_COUNT */
> +#define PRM_PSCON_HG_EN (1 << 24)
> +#define PRM_PSCON_HG_RAMPUP (1 << 25)
nit: use BIT()
> #ifdef CONFIG_SMP
>
> struct omap4_cpu_pm_info {
> @@ -337,6 +341,28 @@ int __cpuinit omap4_hotplug_cpu(unsigned int cpu, unsigned int power_state)
> return 0;
> }
>
> +/**
> + * enable_mercury_retention_mode: Enable OMAP5 mercury retention feature
> + *
> + * OMAP5 devices supports SR3-APG (mercury) power management technology to
> + * reduce leakage. It allows for full logic and memories retention on
> + * MPU_C0 and MPU_C1 and is controlled by the PRCM_MPU. The function enable
> + * the mercury retention feature.
> + */
> +static void enable_mercury_retention_mode(void)
__init ?
This is very OMAP5 specific (unless you generalize the offsets used) so
should this have omap5_ prefix?
Kevin
> +{
> + u32 reg;
> +
> + /*
> + * To enable mercury mode, both HG_EN and HG_RAMPUP needs to be
> + * enabled from PRM_PSCON_COUNT register.
> + */
> + reg = omap4_prcm_mpu_read_inst_reg(OMAP54XX_PRCM_MPU_DEVICE_INST,
> + OMAP54XX_PRCM_MPU_PRM_PSCON_COUNT_OFFSET);
> + reg |= PRM_PSCON_HG_EN | PRM_PSCON_HG_RAMPUP;
> + omap4_prcm_mpu_write_inst_reg(reg, OMAP54XX_PRCM_MPU_DEVICE_INST,
> + OMAP54XX_PRCM_MPU_PRM_PSCON_COUNT_OFFSET);
nit: when I see 'reg', I expect it to be a register/offset. But this is
a register value. Maybe use 'val' instead as you've done elsewhere in
this series.
Kevin
> +}
>
> /*
> * Initialise OMAP4 MPUSS
> @@ -415,6 +441,7 @@ int __init omap4_mpuss_init(void)
> cpu_context_offset = OMAP4_RM_CPU0_CPU0_CONTEXT_OFFSET;
> } else if (soc_is_omap54xx()) {
> cpu_context_offset = OMAP54XX_RM_CPU0_CPU0_CONTEXT_OFFSET;
> + enable_mercury_retention_mode();
> }
>
> return 0;
--
To unsubscribe from this list: send the line "unsubscribe linux-omap" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
