[PATCH 04/10] ARM: OMAP5 / DRA7: PM: Enable Mercury retention mode on CPUx powerdomains
From: nm@ti.com (Nishanth Menon)
Date: 2014-08-22 14:05:46
Also in:
linux-omap, lkml
Subsystem:
arm port, omap2+ support, the rest · Maintainers:
Russell King, Aaro Koskinen, Andreas Kemnade, Kevin Hilman, Roger Quadros, Tony Lindgren, Linus Torvalds
From: Santosh Shilimkar <redacted>
In addition to the standard power-management technique, the OMAP5 / DRA7
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. Only "Fast-mode" is supported on the
OMAP5 and DRA7 family of processors.
Signed-off-by: Santosh Shilimkar <redacted>
[nm at ti.com: minor consolidation]
Signed-off-by: Nishanth Menon <nm@ti.com>
---
This has a minor checkpatch warning for aligning with '(', but that
when fixed results in over 80 char warning. So choose '(' check instead :D.
arch/arm/mach-omap2/omap-mpuss-lowpower.c | 16 ++++++++++++++++
1 file changed, 16 insertions(+)
diff --git a/arch/arm/mach-omap2/omap-mpuss-lowpower.c b/arch/arm/mach-omap2/omap-mpuss-lowpower.c
index 63a1dd7..fad6e8c 100644
--- a/arch/arm/mach-omap2/omap-mpuss-lowpower.c
+++ b/arch/arm/mach-omap2/omap-mpuss-lowpower.c@@ -321,6 +321,21 @@ int 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); + /* Enable HG_EN, HG_RAMPUP = fast mode */ + 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)
@@ -397,6 +412,7 @@ int __init omap4_mpuss_init(void) cpu_context_offset = OMAP4_RM_CPU0_CPU0_CONTEXT_OFFSET; } else if (soc_is_omap54xx() || soc_is_dra7xx()) { cpu_context_offset = OMAP54XX_RM_CPU0_CPU0_CONTEXT_OFFSET; + enable_mercury_retention_mode(); } return 0;
--
1.7.9.5