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.
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@xxxxxx>
---
arch/arm/mach-omap2/omap-mpuss-lowpower.c | 17 +++++++++++++++++
1 file changed, 17 insertions(+)
diff --git a/arch/arm/mach-omap2/omap-mpuss-lowpower.c b/arch/arm/mach-omap2/omap-mpuss-lowpower.c
index bcd2efb..9fda96b 100644
--- a/arch/arm/mach-omap2/omap-mpuss-lowpower.c
+++ b/arch/arm/mach-omap2/omap-mpuss-lowpower.c
@@ -360,6 +360,20 @@ int __cpuinit omap4_hotplug_cpu(unsigned int cpu, unsigned int power_state)
/*
+ * Enable Mercury Fast HG retention mode by default.
+ */
+static void enable_mercury_retention_mode(void)
+{
+ u32 reg;
+
+ reg = omap4_prcm_mpu_read_inst_reg(OMAP54XX_PRCM_MPU_DEVICE_INST,
+ OMAP54XX_PRCM_MPU_PRM_PSCON_COUNT_OFFSET);
+ reg |= BIT(24) | BIT(25);
+ omap4_prcm_mpu_write_inst_reg(reg, OMAP54XX_PRCM_MPU_DEVICE_INST,
+ OMAP54XX_PRCM_MPU_PRM_PSCON_COUNT_OFFSET);
+}
+
+/*
* Initialise OMAP4 MPUSS
*/
int __init omap4_mpuss_init(void)
@@ -438,6 +452,9 @@ int __init omap4_mpuss_init(void)
cpu_context_offset = OMAP54XX_RM_CPU0_CPU0_CONTEXT_OFFSET;
}
+ if (soc_is_omap54xx())
+ enable_mercury_retention_mode();
+
return 0;
}
--
1.7.9.5
--
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
