[PATCH v2] AM3517 : support for suspend/resume

From: Abhilash K V
Date: Wed Sep 14 2011 - 09:49:15 EST


This patch-set adds support for suspension to RAM and
resumption on the AM3517. This includes:
1. Patch to disable dynamic sleep (as it is not supported
on AM35xx).
2. Imported the unique suspend/resume sequence for AM3517,
contained in the new file arch/arm/mach-omap2/sleep3517.S.

Caveat: If "no_console_suspend" is enabled (via boot-args),the
device doesnot resume but simply hangs.
Kevin's fix below should fix this:
http://marc.info/?l=linux-omap&m=131593828001388&w=2#1

Signed-off-by: Ranjith Lohithakshan <ranjithl@xxxxxx>
Reviewed-by: Vaibhav Hiremath <hvaibhav@xxxxxx>
Signed-off-by: Abhilash K V <abhilash.kv@xxxxxx>
---
This patch is dependent on the following patch-sets:
* [PATCH v3 0/2] AM3517: Booting up
at http://marc.info/?l=linux-omap&m=131548349725176&w=2
* [PATCH v2 0/3] AM35x: Adding PM init
at http://marc.info/?l=linux-kernel&m=131548606728209&w=2

The patches are tested on master of tmlind/linux-omap-2.6.git.
Kernel version is 3.1-rc3 and last commit on top of which these patches
were added is:
b148d763841161894ed6629794064065a834aa2b: Linux-omap rebuilt: Updated to
use omap_sdrc_init

with the folowing commit reverted:
f3637a5f2e2eb391ff5757bc83fb5de8f9726464: irq: Always set IRQF_ONESHOT
if no primary handler is specified

Changes in v2:
* Synchronised with the cleaned-up suspend-resume code for OMAP3
* Removed unused *_get_restore_pointer code
* Added SECURE_SRAM feature to disallow saving and restoring
secure ram context for AM35x
* Compacted the number of patches by squashing three closely coupled
ones and eliminating one that was no longer needed.

arch/arm/mach-omap2/Makefile | 3 +-
arch/arm/mach-omap2/id.c | 4 +-
arch/arm/mach-omap2/pm.h | 3 +
arch/arm/mach-omap2/pm34xx.c | 21 ++++-
arch/arm/mach-omap2/sleep3517.S | 156 +++++++++++++++++++++++++++++++++
arch/arm/plat-omap/include/plat/cpu.h | 2 +
6 files changed, 183 insertions(+), 6 deletions(-)
create mode 100644 arch/arm/mach-omap2/sleep3517.S

diff --git a/arch/arm/mach-omap2/Makefile b/arch/arm/mach-omap2/Makefile
index 590e797..37f62ae 100644
--- a/arch/arm/mach-omap2/Makefile
+++ b/arch/arm/mach-omap2/Makefile
@@ -61,7 +61,7 @@ endif
ifeq ($(CONFIG_PM),y)
obj-$(CONFIG_ARCH_OMAP2) += pm24xx.o
obj-$(CONFIG_ARCH_OMAP2) += sleep24xx.o
-obj-$(CONFIG_ARCH_OMAP3) += pm34xx.o sleep34xx.o \
+obj-$(CONFIG_ARCH_OMAP3) += pm34xx.o sleep34xx.o sleep3517.o \
cpuidle34xx.o
obj-$(CONFIG_ARCH_OMAP4) += pm44xx.o
obj-$(CONFIG_PM_DEBUG) += pm-debug.o
@@ -70,6 +70,7 @@ obj-$(CONFIG_OMAP_SMARTREFLEX_CLASS3) += smartreflex-class3.o

AFLAGS_sleep24xx.o :=-Wa,-march=armv6
AFLAGS_sleep34xx.o :=-Wa,-march=armv7-a$(plus_sec)
+AFLAGS_sleep3517.o :=-Wa,-march=armv7-a$(plus_sec)

ifeq ($(CONFIG_PM_VERBOSE),y)
CFLAGS_pm_bus.o += -DDEBUG
diff --git a/arch/arm/mach-omap2/id.c b/arch/arm/mach-omap2/id.c
index da71098..3e40c02 100644
--- a/arch/arm/mach-omap2/id.c
+++ b/arch/arm/mach-omap2/id.c
@@ -202,7 +202,9 @@ static void __init omap3_check_features(void)
if (cpu_is_omap3630())
omap_features |= OMAP3_HAS_192MHZ_CLK;
if (!cpu_is_omap3505() && !cpu_is_omap3517())
- omap_features |= (OMAP3_HAS_IO_WAKEUP | OMAP3_HAS_SR);
+ omap_features |= (OMAP3_HAS_IO_WAKEUP
+ | OMAP3_HAS_SR
+ | OMAP3_HAS_SECURE_SRAM);

omap_features |= OMAP3_HAS_SDRC;

diff --git a/arch/arm/mach-omap2/pm.h b/arch/arm/mach-omap2/pm.h
index ce028f6..952eb2b 100644
--- a/arch/arm/mach-omap2/pm.h
+++ b/arch/arm/mach-omap2/pm.h
@@ -82,10 +82,13 @@ extern unsigned int omap24xx_cpu_suspend_sz;

/* 3xxx */
extern void omap34xx_cpu_suspend(int save_state);
+extern void omap3517_cpu_suspend(int save_state);

/* omap3_do_wfi function pointer and size, for copy to SRAM */
extern void omap3_do_wfi(void);
+extern void omap3517_do_wfi(void);
extern unsigned int omap3_do_wfi_sz;
+extern unsigned int omap3517_do_wfi_sz;
/* ... and its pointer from SRAM after copy */
extern void (*omap3_do_wfi_sram)(void);

diff --git a/arch/arm/mach-omap2/pm34xx.c b/arch/arm/mach-omap2/pm34xx.c
index 7255d9b..44f7bac 100644
--- a/arch/arm/mach-omap2/pm34xx.c
+++ b/arch/arm/mach-omap2/pm34xx.c
@@ -80,6 +80,7 @@ static LIST_HEAD(pwrst_list);

static int (*_omap_save_secure_sram)(u32 *addr);
void (*omap3_do_wfi_sram)(void);
+void (*omap3517_do_wfi_sram)(void);

static struct powerdomain *mpu_pwrdm, *neon_pwrdm;
static struct powerdomain *core_pwrdm, *per_pwrdm;
@@ -323,7 +324,10 @@ static void omap34xx_save_context(u32 *save)

static int omap34xx_do_sram_idle(unsigned long save_state)
{
- omap34xx_cpu_suspend(save_state);
+ if (cpu_is_omap3505() || cpu_is_omap3517())
+ omap3517_cpu_suspend(save_state);
+ else
+ omap34xx_cpu_suspend(save_state);
return 0;
}

@@ -485,6 +489,8 @@ console_still_active:

int omap3_can_sleep(void)
{
+ if (cpu_is_omap3505() || cpu_is_omap3517())
+ return 0;
if (!omap_uart_can_sleep())
return 0;
return 1;
@@ -843,11 +849,18 @@ static int __init clkdms_setup(struct clockdomain *clkdm, void *unused)
*/
void omap_push_sram_idle(void)
{
- omap3_do_wfi_sram = omap_sram_push(omap3_do_wfi, omap3_do_wfi_sz);
+ if (cpu_is_omap3505() || cpu_is_omap3517())
+ omap3517_do_wfi_sram = omap_sram_push(omap3517_do_wfi,
+ omap3517_do_wfi_sz);
+ else
+ omap3_do_wfi_sram = omap_sram_push(omap3_do_wfi,
+ omap3_do_wfi_sz);

if (omap_type() != OMAP2_DEVICE_TYPE_GP)
- _omap_save_secure_sram = omap_sram_push(save_secure_ram_context,
- save_secure_ram_context_sz);
+ if (omap3_has_secure_sram())
+ _omap_save_secure_sram = omap_sram_push(
+ save_secure_ram_context,
+ save_secure_ram_context_sz);
}

static void __init pm_errata_configure(void)
diff --git a/arch/arm/mach-omap2/sleep3517.S b/arch/arm/mach-omap2/sleep3517.S
new file mode 100644
index 0000000..a4147bd
--- /dev/null
+++ b/arch/arm/mach-omap2/sleep3517.S
@@ -0,0 +1,156 @@
+/*
+ * AM3505/3517 Sleep Code.
+ * Ranjith Lohithakshan <ranjithl@xxxxxx>
+ *
+ * Copyright (C) 2009 Texas Instruments Incorporated - http://www.ti.com/
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation version 2.
+ *
+ * This program is distributed "as is" WITHOUT ANY WARRANTY of any
+ * kind, whether express or implied; without even the implied warranty
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/linkage.h>
+#include <asm/assembler.h>
+#include <plat/sram.h>
+#include <mach/io.h>
+
+#include "cm2xxx_3xxx.h"
+#include "prm2xxx_3xxx.h"
+#include "sdrc.h"
+#include "control.h"
+
+#define CM_IDLEST1_CORE_V OMAP34XX_CM_REGADDR(CORE_MOD, CM_IDLEST1)
+#define CM_CLKST_CORE_V OMAP34XX_CM_REGADDR(CORE_MOD,\
+ OMAP3430_CM_CLKSTST)
+#define CM_ICLKEN1_CORE_V OMAP34XX_CM_REGADDR(CORE_MOD, CM_ICLKEN1)
+
+#define EMIF_PM_CTR_V OMAP2_L3_IO_ADDRESS(0x6D000038)
+#define OMAP3517_CONF1_REG_V OMAP2_L4_IO_ADDRESS(0x48002584)
+
+/*
+ * Forces OMAP into idle state
+ *
+ * omap3517_suspend() - This bit of code just executes the WFI
+ * for normal idles.
+ *
+ */
+ENTRY(omap3517_cpu_suspend)
+ stmfd sp!, {r4-r12, lr} @ save registers on stack
+loop:
+ /*b loop*/ @Enable to debug by stepping through code
+ ldr r4, omap3517_do_wfi_sram_addr
+ ldr r5, [r4]
+ /*
+ * Since OFF mode is unsupported r0 is always 0, and so no need to
+ * save context
+ */
+ bx r5 @ jump to the WFI code in SRAM
+/*
+ * Local variables
+ */
+omap3517_do_wfi_sram_addr:
+ .word omap3517_do_wfi_sram
+
+/* ===================================
+ * == WFI instruction => Enter idle ==
+ * ===================================
+ */
+
+/*
+ * Do WFI instruction
+ * Includes the resume path for non-OFF modes
+ *
+ * This code gets copied to internal SRAM and is accessible
+ * from both SDRAM and SRAM
+ * Always executed from SRAM (omap3517_do_wfi_sram),as AM35x does not
+ * support OFF mode
+ */
+ .align 3
+ENTRY(omap3517_do_wfi)
+ /* Put EMIF in self-refresh */
+ ldr r4, emif_pm_ctrl
+ ldr r5, [r4]
+ orr r5, r5, #0x200
+ str r5, [r4]
+
+ /* Disable SDRC and Control Module */
+ ldr r4, cm_iclken1_core
+ ldr r5, [r4]
+ str r5, iclk_core_enable
+ ldr r4, cm_iclken1_core
+ ldr r5, clk_core_disable
+ str r5, [r4]
+wait_sdrc_ok:
+ ldr r4, cm_idlest1_core
+ ldr r5, [r4]
+ and r5, r5, #0x2
+ cmp r5, #0x2
+ bne wait_sdrc_ok
+
+ /* Gate DDR Phy clock */
+ ldr r4, omap3517_conf1
+ ldr r5, emif_phy_gate
+ str r5, [r4]
+
+ /* Data memory barrier and Data sync barrier */
+ mov r1, #0
+ mcr p15, 0, r1, c7, c10, 4
+ mcr p15, 0, r1, c7, c10, 5
+
+ wfi
+
+ nop
+ nop
+ nop
+ nop
+ nop
+ nop
+ nop
+ nop
+ nop
+ nop
+
+ /* Enable SDRC and Control Module */
+ ldr r4, cm_iclken1_core
+ ldr r5, iclk_core_enable
+ str r5, [r4]
+
+ /* Enable DDR Phy Clock */
+ ldr r4, omap3517_conf1
+ ldr r5, emif_phy_enable
+ str r5, [r4]
+
+ /* Take EMIF out of self-refresh */
+ ldr r4, emif_pm_ctrl
+ ldr r5, [r4]
+ bic r5, r5, #0x200
+ str r5, [r4]
+
+ ldmfd sp!, {r4-r12, pc} @ restore regs and return
+
+clk_core_disable:
+ .word 0x0
+iclk_core_enable:
+ .word 0x0
+emif_phy_gate:
+ .word 0x2620
+emif_phy_enable:
+ .word 0x8620
+cm_idlest1_core:
+ .word CM_IDLEST1_CORE_V
+cm_clkst_core:
+ .word CM_CLKST_CORE_V
+emif_pm_ctrl:
+ .word EMIF_PM_CTR_V
+cm_iclken1_core:
+ .word CM_ICLKEN1_CORE_V
+omap3517_conf1:
+ .word OMAP3517_CONF1_REG_V
+ENTRY(omap3517_do_wfi_sz)
+ .word . - omap3517_do_wfi
+
diff --git a/arch/arm/plat-omap/include/plat/cpu.h b/arch/arm/plat-omap/include/plat/cpu.h
index 294e015..7daeb36 100644
--- a/arch/arm/plat-omap/include/plat/cpu.h
+++ b/arch/arm/plat-omap/include/plat/cpu.h
@@ -492,6 +492,7 @@ extern u32 omap_features;
#define OMAP4_HAS_MPU_1_2GHZ BIT(9)
#define OMAP4_HAS_MPU_1_5GHZ BIT(10)
#define OMAP3_HAS_SR BIT(11)
+#define OMAP3_HAS_SECURE_SRAM BIT(12)


#define OMAP3_HAS_FEATURE(feat,flag) \
@@ -509,6 +510,7 @@ OMAP3_HAS_FEATURE(192mhz_clk, 192MHZ_CLK)
OMAP3_HAS_FEATURE(io_wakeup, IO_WAKEUP)
OMAP3_HAS_FEATURE(sdrc, SDRC)
OMAP3_HAS_FEATURE(sr, SR)
+OMAP3_HAS_FEATURE(secure_sram, SECURE_SRAM)

/*
* Runtime detection of OMAP4 features
--
1.7.1

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