From: Deepak Sikri <deepak.sikri@xxxxxx>
OPEN POINTS: 1. Suspend to RAM support needs to be added.
2. The basic framework added for S2R.
3. SPEAr13xx: The power domains need to be added.
4. Extensive testing needs to be done.
5. For SPEAr13xx: PLL-4 has not been switch off while moving
into sleep. There is some problem in getting the pll back to on.
6. Not functional on SPEAr6XX
Signed-off-by: Deepak Sikri <deepak.sikri@xxxxxx>
Signed-off-by: Rajeev Kumar <rajeev-dlh.kumar@xxxxxx>
Signed-off-by: shiraz hashim <shiraz.hashim@xxxxxx>
Signed-off-by: Viresh Kumar <viresh.kumar@xxxxxx>
---
arch/arm/mach-spear13xx/Makefile | 1 +
arch/arm/mach-spear13xx/include/mach/suspend.h | 47 +++
arch/arm/mach-spear13xx/pm.c | 107 ++++++
arch/arm/mach-spear13xx/sleep.S | 435 ++++++++++++++++++++++++
arch/arm/mach-spear13xx/spear13xx.c | 5 +
arch/arm/mach-spear3xx/include/mach/suspend.h | 44 +++
arch/arm/mach-spear3xx/spear3xx.c | 5 +-
arch/arm/mach-spear6xx/include/mach/suspend.h | 44 +++
arch/arm/mach-spear6xx/spear6xx.c | 9 +-
arch/arm/plat-spear/Makefile | 6 +
arch/arm/plat-spear/pm.c | 104 ++++++
arch/arm/plat-spear/sleep.S | 288 ++++++++++++++++
12 files changed, 1093 insertions(+), 2 deletions(-)
create mode 100644 arch/arm/mach-spear13xx/include/mach/suspend.h
create mode 100644 arch/arm/mach-spear13xx/pm.c
create mode 100644 arch/arm/mach-spear13xx/sleep.S
create mode 100644 arch/arm/mach-spear3xx/include/mach/suspend.h
create mode 100644 arch/arm/mach-spear6xx/include/mach/suspend.h
create mode 100644 arch/arm/plat-spear/pm.c
create mode 100644 arch/arm/plat-spear/sleep.S
diff --git a/arch/arm/mach-spear13xx/Makefile b/arch/arm/mach-spear13xx/Makefile
index 9312fcd..799eefa 100644
--- a/arch/arm/mach-spear13xx/Makefile
+++ b/arch/arm/mach-spear13xx/Makefile
@@ -7,6 +7,7 @@ obj-y += spear13xx.o clock.o fsmc-nor.o
obj-$(CONFIG_SMP) += platsmp.o headsmp.o
obj-$(CONFIG_LOCAL_TIMERS) += localtimer.o
obj-$(CONFIG_PCIEPORTBUS) += pcie.o
+obj-$(CONFIG_PM) += pm.o sleep.o
# spear1300 specific files
obj-$(CONFIG_MACH_SPEAR1300) += spear1300.o
diff --git a/arch/arm/mach-spear13xx/include/mach/suspend.h b/arch/arm/mach-spear13xx/include/mach/suspend.h
new file mode 100644
index 0000000..c8d13e6
--- /dev/null
+++ b/arch/arm/mach-spear13xx/include/mach/suspend.h
@@ -0,0 +1,47 @@
+/*
+ * arch/arm/mach-spear13xx/include/mach/suspend.h
+ *
+ * Sleep mode defines for SPEAr13xx machine family
+ *
+ * Copyright (C) 2010 ST Microelectronics
+ * AUTHOR : Deepak Sikri <deepak.sikri@xxxxxx>
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#ifndef __MACH_SUSPEND_H
+#define __MACH_SUSPEND_H
+
+#include <mach/spear.h>
+
+#ifndef __ASSEMBLER__
+extern void spear_sleep_mode(suspend_state_t state);
+extern unsigned int spear_sleep_mode_sz;
+extern void spear_wakeup(void);
+extern unsigned int spear_wakeup_sz;
+#endif
+
+/* SRAM related defines*/
+#define SRAM_STACK_STRT_OFF 0x500
+#define SRAM_STACK_SCR_OFFS 0xF00
+#define SPEAR_START_SRAM SPEAR13XX_SYSRAM1_BASE
+#define SPEAR_LIMIT_SRAM (SPEAR_START_SRAM + SZ_4K - 1)
+#define SPEAR_SRAM_STACK_PA (SPEAR_START_SRAM + SRAM_STACK_STRT_OFF)
+#define SPEAR_SRAM_SCR_REG (SPEAR_START_SRAM + SRAM_STACK_SCR_OFFS)
+/* SPEAr subsystem physical addresses */
+#define MPMC_BASE_PA SPEAR13XX_MPMC_BASE
+#define MISC_BASE_PA SPEAR13XX_MISC_BASE
+
+/* ARM Modes of Operation */
+#define MODE_USR_32 0x10
+#define MODE_FIQ_32 0x11
+#define MODE_IRQ_32 0x12
+#define MODE_SVC_32 0x13
+#define MODE_ABT_32 0x17
+#define MODE_UND_32 0x1B
+#define MODE_SYS_32 0x1F
+#define MODE_BITS 0x1F
+
+#endif /* __MACH_SUSPEND_H */
diff --git a/arch/arm/mach-spear13xx/pm.c b/arch/arm/mach-spear13xx/pm.c
new file mode 100644
index 0000000..1fe3f54
--- /dev/null
+++ b/arch/arm/mach-spear13xx/pm.c
@@ -0,0 +1,107 @@
+/*
+ * arch/arm/mach-spear13xx/pm.c
+ *
+ * SPEAr13xx Power Management source file
+ *
+ * Copyright (C) 2010 ST Microelectronics
+ * Deepak Sikri <deepak.sikri@xxxxxx>
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#include <linux/suspend.h>
+#include <linux/sysfs.h>
+#include <linux/module.h>
+#include <asm/cacheflush.h>
+#include <mach/irqs.h>
+#include <mach/suspend.h>
+#include <mach/hardware.h>
+
+static int spear_pm_sleep(suspend_state_t state)
+{
+ void (*spear_sram_sleep)(suspend_state_t state) = NULL;
+ void (*spear_sram_wake)(void) = NULL;
+ void *sram_dest = (void *)IO_ADDRESS(SPEAR_START_SRAM);
+
+ if (state == PM_SUSPEND_MEM) {
+ spear_sram_wake = memcpy(sram_dest, (void *)spear_wakeup,
+ spear_wakeup_sz);
+ /* Increment destination pointer by the size copied*/
+ sram_dest += roundup(spear_wakeup_sz, 4);
+ }
+
+ /* Copy the Sleep code on to the SRAM*/
+ spear_sram_sleep = memcpy(sram_dest, (void *)spear_sleep_mode,
+ spear_sleep_mode_sz);
+ flush_cache_all();
+ /* Jump to the suspend routines in sram */
+ spear_sram_sleep(state);
+ return 0;
+}
+
+/*
+ * spear_pm_prepare - Do preliminary suspend work.
+ *
+ */
+static int spear_pm_prepare(void)
+{
+ /* We cannot sleep in idle until we have resumed */
+ disable_hlt();
+ return 0;
+}
+
+/*
+ * spear_pm_enter - Actually enter a sleep state.
+ * @state: State we're entering.
+ *
+ */
+static int spear_pm_enter(suspend_state_t state)
+{
+ int ret;
+
+ switch (state) {
+ case PM_SUSPEND_STANDBY:
+ case PM_SUSPEND_MEM:
+ ret = spear_pm_sleep(state);
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ return ret;
+}
+
+/*
+ * spear_pm_finish - Finish up suspend sequence.
+ *
+ * This is called after we wake back up (or if entering the sleep state
+ * failed).
+ */
+static void spear_pm_finish(void)
+{
+ enable_hlt();
+}
+
+static const struct platform_suspend_ops spear_pm_ops = {
+ .prepare = spear_pm_prepare,
+ .enter = spear_pm_enter,
+ .finish = spear_pm_finish,
+ .valid = suspend_valid_only_mem,
+};
+
+static int __init spear_pm_init(void)
+{
+ void * sram_limit_va = (void *)IO_ADDRESS(SPEAR_LIMIT_SRAM);
+ void * sram_st_va = (void *)IO_ADDRESS(SPEAR_START_SRAM);
+
+ /* In case the suspend code size is more than sram size return */
+ if (spear_sleep_mode_sz > (sram_limit_va - sram_st_va))
+ return -ENOMEM;
+
+ suspend_set_ops(&spear_pm_ops);
+
+ return 0;
+}
+arch_initcall(spear_pm_init);
diff --git a/arch/arm/mach-spear13xx/sleep.S b/arch/arm/mach-spear13xx/sleep.S
new file mode 100644
index 0000000..9c7f12b
--- /dev/null
+++ b/arch/arm/mach-spear13xx/sleep.S
@@ -0,0 +1,435 @@
+/*
+ * linux/arch/arm/mach-spear13xx/sleep.S
+ *
+ * SPEAR13xx specific functions that will run in internal SRAM.
+ * The functions are used in power management.
+ *
+ * Copyright (C) 2010 ST MicroElectronics
+ * Deepak Sikri <deepak.sikri@xxxxxx>
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#include <linux/linkage.h>
+#include <asm/assembler.h>
+#include <mach/hardware.h>
+#include <mach/suspend.h>
+
+/* #define DDR_PLL_SREFRESH */
+/* #define TEST_PWRDOMAINS */
+.text
+ENTRY(spear_wakeup)
+
+spear_wakeup:
+ b spear_wakeup
+ adr r0, spear_sleep_restore
+ bx r0
+
+ENTRY(spear_wakeup_sz)
+ .word . - spear_wakeup
+/*
+ * spear_sleep_mode()
+ * Forces SPEAr into sleep
+ */
+ENTRY(spear_sleep_mode)
+ stmfd sp!, {r0-r12, lr} @ save registers on stack
+ /* Store Stack address in r8 */
+ ldr r8, SRAM_STACK_VA
+
+ /* Store sp and spsr to SDRAM */
+ mov r4, sp
+ mrs r5, spsr
+ mov r6, lr
+ stmia r8!, {r4-r6}
+
+ /* Save all ARM registers */
+ /* Coprocessor access control register */
+ mrc p15, 0, r6, c1, c0, 2
+ stmia r8!, {r6}
+ /* TTBR0, TTBR1 and Translation table base control */
+ mrc p15, 0, r4, c2, c0, 0
+ mrc p15, 0, r5, c2, c0, 1
+ mrc p15, 0, r6, c2, c0, 2
+ stmia r8!, {r4-r6}
+ /*
+ * Domain access control register, data fault status register,
+ * and instruction fault status register
+ */
+ mrc p15, 0, r4, c3, c0, 0
+ mrc p15, 0, r5, c5, c0, 0
+ mrc p15, 0, r6, c5, c0, 1
+ stmia r8!, {r4-r6}
+ /*
+ * Data aux fault status register, instruction aux fault status,
+ * data fault address register and instruction fault address register
+ */
+ mrc p15, 0, r4, c5, c1, 0
+ mrc p15, 0, r5, c5, c1, 1
+ mrc p15, 0, r6, c6, c0, 0
+ mrc p15, 0, r7, c6, c0, 2
+ stmia r8!, {r4-r7}
+ /*
+ * user r/w thread and process ID, user r/o thread and process ID,
+ * priv only thread and process ID, cache size selection
+ */
+ mrc p15, 0, r4, c13, c0, 2
+ mrc p15, 0, r5, c13, c0, 3
+ mrc p15, 0, r6, c13, c0, 4
+ mrc p15, 2, r7, c0, c0, 0
+ stmia r8!, {r4-r7}
+ /* Data TLB lockdown, instruction TLB lockdown registers */
+ mrc p15, 0, r5, c10, c0, 0
+ mrc p15, 0, r6, c10, c0, 1
+ stmia r8!, {r5-r6}
+ /* Secure or non secure vector base address, FCSE PID, Context PID*/
+ mrc p15, 0, r4, c12, c0, 0
+ mrc p15, 0, r5, c13, c0, 0
+ mrc p15, 0, r6, c13, c0, 1
+ stmia r8!, {r4-r6}
+ /* Primary remap, normal remap registers */
+ mrc p15, 0, r4, c10, c2, 0
+ mrc p15, 0, r5, c10, c2, 1
+ stmia r8!, {r4-r5}
+ /* Store current cpsr*/
+ mrs r2, cpsr
+ stmia r8!, {r2}
+ mrc p15, 0, r4, c1, c0, 0
+ /* save control register */
+ stmia r8!, {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
+ dsb
+ isb
+ /* Extract the physical address to jump to */
+ adr r0, mmu_off
+ mov r1, #0xcfffffff
+ and r0, r0, r1
+ ldr r1, =0x20000000
+ orr r0, r0, r1
+ mov r2, r0
+
+ /* Disable MMU */
+ mrc p15, 0, r0, c1, c0, 0
+ ldr r1, DISABLE_I_C_M_V
+ bic r0, r0, r1
+ mcr p15, 0, r0, c1, c0, 0
+ /* Move the Physical address into PC */
+ bx r2
+ nop
+mmu_off:
+ /* Put the DDR in self refresh mode */
+ ldr r6, MISC_BASE_P
+ /* Program MPMC Control Status register in Misc Space */
+ ldr r0, [r6, #0x334]
+ /* Set srefresh_enter bit(2) */
+ orr r0, r0, #0x4
+ str r0, [r6, #0x334]
+wait_till_srefresh_on:
+ ldr r0, [r6, #0x334]
+ /* check for cke_status bit(13) */
+ tst r0, #0x2000
+ beq wait_till_srefresh_on
+
+ /* Put the system in slow mode */
+ ldr r0, [r6, #0x200]
+ bic r0, r0, #0x4
+ /* Set the apt mode bits(2:0) in SCCTRL register */
+ orr r0, r0, #0x2
+ str r0, [r6, #0x200] /* System is now in slow mode */
+wait_till_slow_mode:
+ ldr r0, [r6, #0x200]
+ /* Wait for the mode to be updated */
+ and r0, r0, #0xF0000
+ /* Poll the SCCTRL register status bits (6:3) */
+ cmp r0, #0xA0000
+ bne wait_till_slow_mode
+
+ /*
+ * Put the all the system pll's to off state
+ * The loop of count 3 is provided below to
+ * switch off the pll-1/2/3.
+ * r1 contains the offset for the pll control
+ * registers in the misc space.
+ * DDR pll-4 requires different processing.
+ */
+ ldr r1, MISC_PLL_OFFS
+ ldr r2, =0x0 /* PLL Counter 1, 2, 3, 4 */
+swoff_pll:
+ ldr r0, [r6, r1]
+ /* Clear pll_enable bit(1) of PLL1_CTR register in Misc registers */
+ bic r0, r0, #0x02
+ str r0, [r6, r1]
+ add r1, #0xc
+ add r2, #0x1
+ cmp r2, #0x3 /* Switch off pll-1/2/3 */
+ bne swoff_pll
+
+#ifdef DDR_PLL_SREFRESH
+ /* Switch off pll-4 */
+ ldr r0, [r6, r1]
+ /* Clear pll_enable bit(2) of PLL1_CTR register in Misc registers */
+ bic r0, r0, #0x04
+ str r0, [r6, r1]
+#endif
+
+#ifdef TEST_PWRDOMAINS
+ /* Switch off the undesired PLL's */
+ nop
+ ldr r6, MISC_BASE_P
+ ldr r0, [r6, #0x200]
+ bic r0, r0, #0x7
+ orr r0, r0, #0x2
+ str r0, [r6, #0x200 ]
+wait_ack0:
+ ldr r0, [r6, #0x200]
+ and r0, r0, #0xF0000
+ cmp r0, #0xA0000
+ bne wait_ack0
+ ldr r6, MISC_BASE_P
+ ldr r0, [r6, #0x100]
+
+ /*
+ * Switch off the power domains.
+ * Clear the ack bit
+ */
+ bic r0, r0, #0xc000
+ str r0, [r6, #0x100]
+
+ bic r0, r0, #0x1000
+ str r0, [r6, #0x100]
+
+wait_ack1:
+ ldr r0, [r6, #0x100]
+ tst r0, #0x4000
+ beq wait_ack1
+
+ /* Clear the ack bit */
+ bic r0, r0, #0xc000
+ str r0, [r6, #0x100]
+
+ bic r0, r0, #0x0800
+ str r0, [r6, #0x100]
+wait_ack2:
+ ldr r0, [r6, #0x100]
+ tst r0, #0x4000
+ beq wait_ack2
+
+ /* Clear the ack bit */
+ bic r0, r0, #0xc000
+ str r0, [r6, #0x100]
+
+ bic r0, r0, #0x2400
+ str r0, [r6, #0x100]
+wait_ack3:
+ ldr r0, [r6, #0x100]
+ tst r0, #0x4000
+ beq wait_ack3
+#endif
+ wfi @ wait for interrupt
+ nop
+spear_sleep_restore:
+ /*
+ * Reenable the switched off pll's. The Pll's are
+ * enabled using loop count of 4 to activalte all the
+ * pll-1/2/3/4.
+ * The strobing is done for pll-4 only.
+ */
+
+ ldr r6, MISC_BASE_P
+ ldr r1, MISC_PLL_OFFS
+ ldr r2, =0x0 /* PLL Counter 1, 2, 3, 4 */
+swon_pll_1_3:
+ /* Switch on Pll-1/2/3 */
+ ldr r0, [r6, r1]
+ orr r0, r0, #0x2
+ str r0, [r6, r1]
+pll_lock_1_3:
+ /* Set the pll_lock bit(0) in PLLX_CTR register in misc space*/
+ ldr r5, [r6, r1]
+ and r5, r5, #0x1
+ /* Wait for pll lock status */
+ cmp r5, #0x1
+ bne pll_lock_1_3
+
+ /* Loop for all the pll's */
+ add r1, #0xc
+ add r2, #0x1
+ cmp r2, #0x3 /* Switch on till pll-3 */
+ bne swon_pll_1_3
+
+#ifdef DDR_PLL_SREFRESH
+ /* Switch on PLL-4, strobe the pll also */
+ ldr r0, [r6, r1]
+ ldr r0, PLL_VAL1
+ str r0, [r6, r1]
+ ldr r0, PLL_VAL2
+ str r0, [r6, r1]
+ ldr r0, PLL_VAL3
+ str r0, [r6, r1]
+ ldr r0, PLL_VAL2
+ str r0, [r6, r1]
+pll_lock_4:
+ /* Set the pll_lock bit(0) in PLLX_CTR register in misc space*/
+ ldr r5, [r6, r1]
+ and r5, r5, #0x1
+ /* Wait for pll lock status */
+ cmp r5, #0x1
+ bne pll_lock_4
+#endif
+
+ /* Put the system in normal mode */
+ ldr r0, [r6, #0x200]
+ bic r0, r0, #0x7
+ /* Set the apt mode bits(2:0) in SCCTRL register */
+ orr r0, r0, #0x4
+ str r0, [r6, #0x200] /* System is now in slow mode */
+wait_till_normal_mode:
+ ldr r0, [r6, #0x200]
+ /* Wait for the mode to be updated */
+ and r0, r0, #0xF0000
+ /* Poll the SCCTRL register status bits (6:3) */
+ cmp r0, #0xf0000
+ bne wait_till_normal_mode
+
+ /*
+ * Invalidate all instruction caches to PoU
+ * and flush branch target cache
+ */
+ mov r1, #0
+ mcr p15, 0, r1, c7, c5, 0
+
+ ldr r3, SRAM_STACK_PA
+ ldmia r3!, {r4-r6}
+ mov sp, r4
+ msr spsr_cxsf, r5
+ mov lr, r6
+
+ ldmia r3!, {r4-r9}
+ /* Coprocessor access Control Register */
+ mcr p15, 0, r4, c1, c0, 2
+
+ /* TTBR0 */
+ mcr p15, 0, r5, c2, c0, 0
+ /* TTBR1 */
+ mcr p15, 0, r6, c2, c0, 1
+ /* Translation table base control register */
+ mcr p15, 0, r7, c2, c0, 2
+ /*domain access Control Register */
+ mcr p15, 0, r8, c3, c0, 0
+ /* data fault status Register */
+ mcr p15, 0, r9, c5, c0, 0
+
+ ldmia r3!, {r4-r8}
+ /* instruction fault status Register */
+ mcr p15, 0, r4, c5, c0, 1
+ /*Data Auxiliary Fault Status Register */
+ mcr p15, 0, r5, c5, c1, 0
+ /*Instruction Auxiliary Fault Status Register*/
+ mcr p15, 0, r6, c5, c1, 1
+ /*Data Fault Address Register */
+ mcr p15, 0, r7, c6, c0, 0
+ /*Instruction Fault Address Register*/
+ mcr p15, 0, r8, c6, c0, 2
+ ldmia r3!, {r4-r7}
+
+ /* user r/w thread and process ID */
+ mcr p15, 0, r4, c13, c0, 2
+ /* user ro thread and process ID */
+ mcr p15, 0, r5, c13, c0, 3
+ /*Privileged only thread and process ID */
+ mcr p15, 0, r6, c13, c0, 4
+ /* cache size selection */
+ mcr p15, 2, r7, c0, c0, 0
+ ldmia r3!, {r4-r8}
+ /* Data TLB lockdown registers */
+ mcr p15, 0, r4, c10, c0, 0
+ /* Instruction TLB lockdown registers */
+ mcr p15, 0, r5, c10, c0, 1
+ /* Secure or Nonsecure Vector Base Address */
+ mcr p15, 0, r6, c12, c0, 0
+ /* FCSE PID */
+ mcr p15, 0, r7, c13, c0, 0
+ /* Context PID */
+ mcr p15, 0, r8, c13, c0, 1
+
+ ldmia r3!, {r4-r5}
+ /* primary memory remap register */
+ mcr p15, 0, r4, c10, c2, 0
+ /*normal memory remap register */
+ mcr p15, 0, r5, c10, c2, 1
+
+ /* Restore cpsr */
+ ldmfd r3!, {r4} /*load CPSR from SDRAM*/
+ msr cpsr, r4 /*store cpsr */
+ dsb
+ isb
+ mov r0, #0
+ mcr p15, 0, r0, c7, c5, 4 @ Flush prefetch buffer
+ mcr p15, 0, r0, c7, c5, 6 @ Invalidate branch predictor array
+ mcr p15, 0, r0, c8, c5, 0 @ Invalidate instruction TLB
+ mcr p15, 0, r0, c8, c6, 0 @ Invalidate data TLB
+
+ adr r5, mmu_on
+ mov r1, #0xcfffffff
+ and r5, r5, r1
+ ldr r1, =0x30000000
+ orr r5, r5, r1
+ mov r4, r5
+
+ /* Move the DDR out of self refresh mode */
+ ldr r6, MISC_BASE_P
+ ldr r7, MPMC_BASE_P
+ /* Program MPMC Control Status register in Misc Space */
+ ldr r0, [r6, #0x334]
+ /* Clear srefresh_enter bit(2) */
+ bic r0, r0, #0x4
+ str r0, [r6, #0x334]
+ /* Additional clearance is required in the mpmc space */
+ ldr r0, [r7, #0x2c]
+ /*
+ * Clear bit srefresh bit (2) of MPMC_11 register
+ * The misc wrapper does not works fine by itself till
+ * this bit is also cleared.
+ */
+ bic r0, r0, #0x10000
+ str r0, [r7, #0x2c]
+wait_for_refresh_exit:
+ ldr r0, [r6, #0x334]
+ tst r0, #0x2000
+ bne wait_for_refresh_exit
+
+ ldmfd r3!, {r2}
+ /* restore the MMU control register from stack to enable mmu */
+ mcr p15, 0, r2, c1, c0, 0
+ bx r4
+
+mmu_on:
+ ldmfd sp!, {r0-r12, pc} @ restore regs and return
+ nop
+
+MPMC_BASE_P :
+ .word MPMC_BASE_PA
+MISC_BASE_P :
+ .word MISC_BASE_PA
+SRAM_STACK_VA :
+ .word IO_ADDRESS(SPEAR_SRAM_STACK_PA)
+SRAM_STACK_PA :
+ .word SPEAR_SRAM_STACK_PA
+DISABLE_I_C_M_V:
+ .word 0x1805
+MISC_PLL_OFFS:
+ .word 0x214
+#ifdef DDR_PLL_SREFRESH
+PLL_VAL1:
+ .word 0x060a
+PLL_VAL2:
+ .word 0x060e
+PLL_VAL3:
+ .word 0x0606
+#endif
+ENTRY(spear_sleep_mode_sz)
+ .word . - spear_sleep_mode
diff --git a/arch/arm/mach-spear13xx/spear13xx.c b/arch/arm/mach-spear13xx/spear13xx.c
index cdf132e..08e87d7 100644
--- a/arch/arm/mach-spear13xx/spear13xx.c
+++ b/arch/arm/mach-spear13xx/spear13xx.c
@@ -464,6 +464,11 @@ struct map_desc spear13xx_io_desc[] __initdata = {
.pfn = __phys_to_pfn(SPEAR13XX_SYSRAM0_BASE),
.length = SZ_32K,
.type = MT_DEVICE
+ }, {
+ .virtual = IO_ADDRESS(SPEAR13XX_SYSRAM1_BASE),
+ .pfn = __phys_to_pfn(SPEAR13XX_SYSRAM1_BASE),
+ .length = SZ_1M,
+ .type = MT_MEMORY_NONCACHED
},
};
diff --git a/arch/arm/mach-spear3xx/include/mach/suspend.h b/arch/arm/mach-spear3xx/include/mach/suspend.h
new file mode 100644
index 0000000..a525173
--- /dev/null
+++ b/arch/arm/mach-spear3xx/include/mach/suspend.h
@@ -0,0 +1,44 @@
+/*
+ * arch/arm/mach-spear3xx/include/mach/suspend.h
+ *
+ * Sleep mode defines for SPEAr3xx machine family
+ *
+ * Copyright (C) 2010 ST Microelectronics
+ * AUTHOR : Deepak Sikri <deepak.sikri@xxxxxx>
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#ifndef __MACH_SUSPEND_H
+#define __MACH_SUSPEND_H
+
+#include <mach/spear.h>
+
+#ifndef __ASSEMBLER__
+extern void spear_sleep_mode(suspend_state_t state);
+extern unsigned int spear_sleep_mode_sz;
+#endif
+
+/* SRAM related defines*/
+#define SRAM_STACK_SCR_OFFS 0xF00
+#define SPEAR_START_SRAM SPEAR3XX_ICM1_SRAM_BASE
+#define SPEAR_SRAM_SIZE SZ_4K
+#define SPEAR_SRAM_SCR_REG (SPEAR_START_SRAM + SRAM_STACK_SCR_OFFS)
+/* SPEAr subsystem physical addresses */
+#define SYS_CTRL_BASE_PA SPEAR3XX_ICM3_SYS_CTRL_BASE
+#define MPMC_BASE_PA SPEAR3XX_ICM3_SDRAM_CTRL_BASE
+#define MISC_BASE_PA SPEAR3XX_ICM3_MISC_REG_BASE
+
+/* ARM Modes of Operation */
+#define MODE_USR_32 0x10
+#define MODE_FIQ_32 0x11
+#define MODE_IRQ_32 0x12
+#define MODE_SVC_32 0x13
+#define MODE_ABT_32 0x17
+#define MODE_UND_32 0x1B
+#define MODE_SYS_32 0x1F
+#define MODE_BITS 0x1F
+
+#endif /* __MACH_SUSPEND_H */
diff --git a/arch/arm/mach-spear3xx/spear3xx.c b/arch/arm/mach-spear3xx/spear3xx.c
index c9727ac..2dfa9d5 100644
--- a/arch/arm/mach-spear3xx/spear3xx.c
+++ b/arch/arm/mach-spear3xx/spear3xx.c
@@ -22,6 +22,8 @@
#include <mach/generic.h>
#include <mach/spear.h>
+#define SPEAR3XX_WKUP_SRCS (1 << IRQ_MAC_1 | 1 << IRQ_USB_DEV | \
+ 1 << IRQ_BASIC_RTC | 1 << IRQ_BASIC_GPIO)
/* Add spear3xx machines common devices here */
/* gpio device registeration */
static struct pl061_platform_data gpio_plat_data = {
@@ -246,7 +248,8 @@ void __init spear3xx_init(void)
/* This will initialize vic */
void __init spear3xx_init_irq(void)
{
- vic_init((void __iomem *)VA_SPEAR3XX_ML1_VIC_BASE, 0, ~0, 0);
+ vic_init((void __iomem *)VA_SPEAR3XX_ML1_VIC_BASE, 0, ~0,
+ SPEAR3XX_WKUP_SRCS);
}
/* Following will create static virtual/physical mappings */
diff --git a/arch/arm/mach-spear6xx/include/mach/suspend.h b/arch/arm/mach-spear6xx/include/mach/suspend.h
new file mode 100644
index 0000000..e98e831
--- /dev/null
+++ b/arch/arm/mach-spear6xx/include/mach/suspend.h
@@ -0,0 +1,44 @@
+/*
+ * arch/arm/mach-spear6xx/include/mach/suspend.h
+ *
+ * Sleep mode defines for SPEAr6xx machine family
+ *
+ * Copyright (C) 2010 ST Microelectronics
+ * AUTHOR : Deepak Sikri <deepak.sikri@xxxxxx>
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#ifndef __MACH_SUSPEND_H
+#define __MACH_SUSPEND_H
+
+#include <mach/spear.h>
+
+#ifndef __ASSEMBLER__
+extern void spear_sleep_mode(suspend_state_t state);
+extern unsigned int spear_sleep_mode_sz;
+#endif
+
+/* SRAM related defines*/
+#define SRAM_STACK_SCR_OFFS 0xF00
+#define SPEAR_START_SRAM SPEAR6XX_ICM1_SRAM_BASE
+#define SPEAR_SRAM_SIZE SZ_4K
+#define SPEAR_SRAM_SCR_REG (SPEAR_START_SRAM + SRAM_STACK_SCR_OFFS)
+/* SPEAr subsystem physical addresses */
+#define SYS_CTRL_BASE_PA SPEAR6XX_ICM3_SYS_CTRL_BASE
+#define MPMC_BASE_PA SPEAR6XX_ICM3_SDRAM_CTRL_BASE
+#define MISC_BASE_PA SPEAR6XX_ICM3_MISC_REG_BASE
+
+/* ARM Modes of Operation */
+#define MODE_USR_32 0x10
+#define MODE_FIQ_32 0x11
+#define MODE_IRQ_32 0x12
+#define MODE_SVC_32 0x13
+#define MODE_ABT_32 0x17
+#define MODE_UND_32 0x1B
+#define MODE_SYS_32 0x1F
+#define MODE_BITS 0x1F
+
+#endif /* __MACH_SUSPEND_H */
diff --git a/arch/arm/mach-spear6xx/spear6xx.c b/arch/arm/mach-spear6xx/spear6xx.c
index cc2692e..8334841 100644
--- a/arch/arm/mach-spear6xx/spear6xx.c
+++ b/arch/arm/mach-spear6xx/spear6xx.c
@@ -24,6 +24,12 @@
#include <mach/generic.h>
#include <mach/spear.h>
+/* The wake sources are routed through vic-2 */
+#define SPEAR6XX_WKUP_SRCS_VIC2 (1 << (IRQ_GMAC_1 - 32) | \
+ 1 << (IRQ_USB_DEV - 32) | \
+ 1 << (IRQ_BASIC_RTC - 32) |\
+ 1 << (IRQ_BASIC_GPIO - 32))
+
/* Add spear6xx machines common devices here */
/* CLCD device registration */
@@ -400,7 +406,8 @@ void __init spear6xx_init(void)
void __init spear6xx_init_irq(void)
{
vic_init((void __iomem *)VA_SPEAR6XX_CPU_VIC_PRI_BASE, 0, ~0, 0);
- vic_init((void __iomem *)VA_SPEAR6XX_CPU_VIC_SEC_BASE, 32, ~0, 0);
+ vic_init((void __iomem *)VA_SPEAR6XX_CPU_VIC_SEC_BASE, 32, ~0,
+ SPEAR6XX_WKUP_SRCS_VIC2);
}
/* Following will create static virtual/physical mappings */
diff --git a/arch/arm/plat-spear/Makefile b/arch/arm/plat-spear/Makefile
index 0e2cf75..1c8ee4a 100644
--- a/arch/arm/plat-spear/Makefile
+++ b/arch/arm/plat-spear/Makefile
@@ -6,6 +6,7 @@
obj-y := clcd.o clock.o pll_clk.o smi.o time.o
obj-$(CONFIG_ARCH_SPEAR3XX) += shirq.o padmux.o
+
obj-$(CONFIG_MACH_SPEAR310) += plgpio.o
obj-$(CONFIG_MACH_SPEAR320) += plgpio.o
obj-$(CONFIG_SPEAR_PWM) += pwm.o
@@ -16,3 +17,8 @@ obj-$(CONFIG_BOARD_SPEAR300_EVB) += i2c_eval_board.o
obj-$(CONFIG_BOARD_SPEAR310_EVB) += i2c_eval_board.o
obj-$(CONFIG_BOARD_SPEAR320_EVB) += i2c_eval_board.o
obj-$(CONFIG_BOARD_SPEAR600_EVB) += i2c_eval_board.o
+
+ifeq ($(CONFIG_PM),y)
+obj-$(CONFIG_ARCH_SPEAR3XX) += pm.o sleep.o
+obj-$(CONFIG_ARCH_SPEAR6XX) += pm.o sleep.o
+endif
diff --git a/arch/arm/plat-spear/pm.c b/arch/arm/plat-spear/pm.c
new file mode 100644
index 0000000..df7c7a1
--- /dev/null
+++ b/arch/arm/plat-spear/pm.c
@@ -0,0 +1,104 @@
+/*
+ * arch/arm/plat-spear/pm.c
+ *
+ * SPEAr3xx & SPEAr6xx Power Management source file
+ *
+ * Copyright (C) 2010 ST Microelectronics
+ * Deepak Sikri <deepak.sikri@xxxxxx>
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#include <linux/suspend.h>
+#include <linux/sysfs.h>
+#include <linux/module.h>
+#include <linux/io.h>
+#include <asm/cacheflush.h>
+#include <mach/irqs.h>
+#include <mach/suspend.h>
+
+static void (*saved_idle)(void);
+static void __iomem *spear_sram_base;
+
+static int spear_pm_sleep(suspend_state_t state)
+{
+ void (*spear_sram_sleep)(suspend_state_t state) = NULL;
+
+ /* Copy the Sleep code on to the SRAM*/
+ spear_sram_sleep = memcpy((void *)spear_sram_base,
+ (void *)spear_sleep_mode, spear_sleep_mode_sz);
+ flush_cache_all();
+ /* Jump to the suspend routines in sram */
+ spear_sram_sleep(state);
+ return 0;
+}
+
+/*
+ * spear_pm_prepare - Do preliminary suspend work.
+ *
+ */
+static int spear_pm_prepare(void)
+{
+ /* We cannot sleep in idle until we have resumed */
+ saved_idle = pm_idle;
+ pm_idle = NULL;
+ return 0;
+}
+
+/*
+ * spear_pm_enter - Actually enter a sleep state.
+ * @state: State we're entering.
+ *
+ */
+static int spear_pm_enter(suspend_state_t state)
+{
+ int ret;
+
+ switch (state) {
+ case PM_SUSPEND_STANDBY:
+ case PM_SUSPEND_MEM:
+ ret = spear_pm_sleep(state);
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ return ret;
+}
+
+/*
+ * spear_pm_finish - Finish up suspend sequence.
+ *
+ * This is called after we wake back up (or if entering the sleep state
+ * failed).
+ */
+static void spear_pm_finish(void)
+{
+ pm_idle = saved_idle;
+}
+
+static const struct platform_suspend_ops spear_pm_ops = {
+ .prepare = spear_pm_prepare,
+ .enter = spear_pm_enter,
+ .finish = spear_pm_finish,
+ .valid = suspend_valid_only_mem,
+};
+
+static int __init spear_pm_init(void)
+{
+
+ spear_sram_base = ioremap(SPEAR_START_SRAM, SPEAR_SRAM_SIZE);
+
+ if (!spear_sram_base)
+ return -ENOMEM;
+
+ /* In case the suspend code size is more than sram size return */
+ if (spear_sleep_mode_sz > (SPEAR_SRAM_SIZE))
+ return -ENOMEM;
+
+ suspend_set_ops(&spear_pm_ops);
+ return 0;
+}
+arch_initcall(spear_pm_init);
diff --git a/arch/arm/plat-spear/sleep.S b/arch/arm/plat-spear/sleep.S
new file mode 100644
index 0000000..5347789
--- /dev/null
+++ b/arch/arm/plat-spear/sleep.S
@@ -0,0 +1,288 @@
+/*
+ * arch/arm/plat-spear/sleep.S
+ *
+ * SPEAR3xx and SPEAR6xx specific functions that will run in
+ * internal SRAM. The functions are used in power management.
+ *
+ * Copyright (ST) 2010 Deepak Sikri <deepak.sikri@.com>
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#include <linux/linkage.h>
+#include <asm/assembler.h>
+#include <mach/hardware.h>
+#include <mach/suspend.h>
+
+.text
+ENTRY(spear_sleep_mode)
+ stmfd sp!, {r0-r12, lr}
+
+ /* Latch some of MMU registers on to stack */
+ mrc p15, 0, r0, c5, c0, 0 /* FSR--Domain Fault */
+ mrc p15, 0, r1, c5, c0, 1 /* FSR--Instruction Fault */
+ mrc p15, 0, r2, c6, c0, 0 /* FAR */
+ mrc p15, 0, r3, c9, c0, 0 /* Read Dcache Lockdown */
+ mrc p15, 0, r4, c9, c0, 1 /* Read ICache Lockdown */
+ mrc p15, 0, r5, c9, c1, 0 /* Read Data TLB */
+ mrc p15, 0, r6, c9, c1, 1 /* Read Instr TCM region register */
+
+ mrc p15, 0, r7, c10, c0, 0 /* Data TLBLock Down operation */
+ mrc p15, 0, r8, c13, c0, 0 /* FCSE--PID */
+ mrc p15, 0, r9, c13, c0, 1 /* Context-ID */
+
+ /* Save all these registers onto the stack */
+ stmfd sp!, {r0-r9}
+ /* Save the stack pointer */
+ mov r3, sp
+ /* Store the two mode registers */
+ stmfd r3!, {sp, lr}
+ /* Save the current mode with irq disabled */
+ mrs r0, cpsr
+ stmfd r3!, {r0}
+ /*
+ * Save the MMU registers on the SRAM Stack
+ * Domain Register on Back-up RAM structure
+ */
+ mrc p15, 0, r2, c3, c0, 0
+ /* TTB Register */
+ mrc p15, 0, r1, c2, c0, 0
+ /* MMU Enable Register */
+ mrc p15, 0, r0, c1, c0, 0
+ stmfd r3!, {r0, r1, r2}
+ /*
+ * Capture the Physical Address.
+ * This will be used once MMU is Off
+ */
+ adr r0, mmu_off
+ adr r1, spear_sleep_mode
+ /* Store the virtual address on to DDR */
+ stmfd r3!, {r1}
+ sub r1, r0, r1
+ ldr r0, SRAM_START_P
+ add r2, r1, r0
+
+ /* Disable MMU */
+ mrc p15, 0, r0, c1, c0, 0
+ ldr r1, DISABLE_I_C_M_V
+ bic r0, r0, r1
+ mcr p15, 0, r0, c1, c0, 0
+ /* Move the Physical address into PC */
+ bx r2
+
+ /*
+ * This portion of code is executed from SRAM
+ * post MMU has been turned off
+ */
+mmu_off:
+ /* Store the DDR stack address onto scratch pad location */
+ ldr r0, SCRATCH_PAD
+ str r3, [r0]
+
+ ldr r6, MISC_BASE_P
+ ldr r7, MPMC_BASE_P
+ ldr r8, SYS_CTRL_BASE_P
+
+ /*
+ * Put SDRAM in self-refresh mode
+ * Clear START bit(24) of MEMCTL_GP_03 register in MPMC
+ */
+ ldr r0, [r7, #0x1c]
+ ldr r4, =0x1000000
+ /* Begin the command processing in controller */
+ bic r0, r0, r4
+ str r0, [r7, #0x1c]
+ ldr r0, [r7, #0x1c]
+ /* set the SREFRESH bit(16) */
+ ldr r4, =0x10000
+ orr r0, r0, r4
+ str r0, [r7, #0x1c]
+
+ /* Put the DDR into low power mode */
+ ldr r0, [r6, #0xf0]
+ ldr r4, =0x00000001
+ /* Clear DDR_LOW_POWER_DDR2_MODE bit(1) of DDR_PAD register */
+ bic r0, r0, r4
+ str r0, [r6, #0xf0]
+
+ /* Put the system in slow mode, use system controller */
+ ldr r0, [r8]
+ bic r0, r0, #0x4
+ /* Set the apt mode bits(2:0) in SCCTRL register */
+ orr r0, r0, #0x2
+ str r0, [r8] /* System is now in slow mode */
+
+wait_till_slow_mode:
+ ldr r0, [r8]
+ and r0, r0, #0x78 /* Wait for the mode to be updated */
+ cmp r0, #0x10 /* Poll the SCCTRL register status bits (6:3) */
+ bne wait_till_slow_mode
+
+ /* Put the Pll-1 to off. */
+ ldr r0, [r6, #0x08]
+ /* Clear pll_enable bit(2) of PLL1_CTR register in Misc registers */
+ bic r0, r0, #0x04
+ str r0, [r6, #0x08]
+
+ /* Put the Pll-2 to off */
+ ldr r0, [r6, #0x14]
+ /* Clear pll_enable bit(2) of PLL2_CTR register in Misc registers */
+ bic r0, r0, #0x04
+ str r0, [r6, #0x14]
+ mov r2, #0
+ /* Put the system in sleep */
+ ldr r0, [r8]
+ /* Set the apt mode bits(2:0) in SCCTRL register */
+ bic r0, r0, #0x7
+#ifdef TEST_SLOW
+ orr r0, r0, #0x2 /* Slow Mode */
+#endif
+ str r0, [r8]
+ /* Put system in WFI */
+ mcr p15, 0, r2, c7, c0, 4
+wakeup_addr:
+ ldr r6, MISC_BASE_P
+ ldr r7, MPMC_BASE_P
+ ldr r8, SYS_CTRL_BASE_P
+ /* Reenable pll1 and pll2 */
+ ldr r0, PLL_VAL1
+ str r0, [r6, #0x08]
+ str r0, [r6, #0x14]
+ ldr r0, PLL_VAL2
+ str r0, [r6, #0x08]
+ str r0, [r6, #0x14]
+ /* Strobe */
+ ldr r2, PLL_VAL3
+ str r2, [r6, #0x08]
+ str r2, [r6, #0x14]
+ ldr r2, PLL_VAL2
+ str r2, [r6, #0x08]
+ str r2, [r6, #0x14]
+pll1_lock_1:
+ /* Set the pll_lock bit(0) in PLL1_CTR register in misc space*/
+ ldr r2, [r6, #0x08]
+ and r2, r2, #0x1
+ /* Wait for pll-1 lock status */
+ cmp r2, #0x1
+ bne pll1_lock_1
+
+pll2_lock_2:
+ /* Set the pll_lock bit(0) in PLL2_CTR register in misc space*/
+ ldr r2, [r6, #0x14]
+ and r2, r2, #0x1
+ /* Wait for pll-2 lock status */
+ cmp r2, #0x1
+ bne pll2_lock_2
+
+ /* Move the system in Normal mode, use system controller */
+ ldr r3, [r8]
+ /* Set the apt mode bits(2:0) in SCCTRL register */
+ bic r3, r3, #0x7
+ orr r3, r3, #0x4
+ str r3, [r8]
+
+wait_till_norm_mode:
+ ldr r3, [r8]
+ and r3, r3, #0x78
+ cmp r3, #0x20 /* Poll the SCCTRL register status bits (6:3) */
+ bne wait_till_norm_mode
+
+ /* Resume the DDR from Low power mode. */
+ ldr r0, [r6, #0xf0]
+ /* Set DDR_LOW_POWER_DDR2_MODE bit(1) of DDR_PAD register */
+ orr r0, r0, #0x01
+ str r0, [r6, #0xf0]
+
+ /* Exit DDR-SDRAM from self-refresh mode */
+ ldr r1, [r7, #0x1c]
+ /* clear the SREFRESH bit(16) */
+ ldr r4, =0x10000
+ bic r1, r1, r4
+ str r1, [r7, #0x1c]
+
+ /* Begin the command processing in controller */
+ ldr r4, =0x1000000
+ /* Set START bit(24) of MEMCTL_GP_03 register in MPMC*/
+ orr r1, r1, r4
+ str r1, [r7, #0x1c]
+
+ mov r0, r0
+ /* Start the Restore Processing */
+ ldr r0, SCRATCH_PAD
+ ldr r6, [r0]
+
+ /* Restore the Virtual Address to be used */
+ /* Once MMU is made on */
+ ldr r0, SRAM_START_P
+ adr r1, mmu_on
+ sub r0, r1, r0
+ /* Get the physical Address */
+ mov r3, #0xc0000000
+ sub r6, r6, r3
+ /* Fetch the sram virtual address */
+ ldmfd r6!, {r1}
+ add r4, r1, r0
+
+ /* Fetch the MMU Related information latched on SDRAM */
+ ldmfd r6!, {r0, r1, r2}
+ /* Enable the MMU */
+ mcr p15, 0, r2, c3, c0, 0
+ mcr p15, 0, r1, c2, c0, 0
+ mcr p15, 0, r0, c1, c0, 0
+ bx r4
+mmu_on:
+ add r6, r6, r3
+ /* Store the value of cpsr in R0 */
+ mrs r0, cpsr
+ bic r0, r0, #MODE_BITS
+
+ /* Here we will restore our cpsr IRQ/FIQ Disabled */
+ ldr r0, [r6]
+ msr cpsr_cxsf, r0
+ add r6, r6, #4
+
+ /* Now only two user-mode registers are left */
+ ldmfd r6!, {sp, lr}
+ mov r0, r0
+
+ /* Restore stack pointer for the current mode */
+ mov sp, r6
+
+ ldmfd sp!, {r0-r9}
+ mcr p15, 0, r0, c5, c0, 0 /* FSR--Domain Fault */
+ mcr p15, 0, r1, c5, c0, 1 /* FSR--Instruction Fault */
+ mcr p15, 0, r2, c6, c0, 0 /* FAR */
+ mcr p15, 0, r3, c9, c0, 0 /* Read Dcache Lockdown */
+ mcr p15, 0, r4, c9, c0, 1 /* Read ICache Lockdown */
+ mcr p15, 0, r5, c9, c1, 0 /* Read Data TLB */
+ mcr p15, 0, r6, c9, c1, 1 /* Read Instruction Lockdown */
+
+ mcr p15, 0, r7, c10, c0, 0 /* Data TLB LockDown operation */
+ mcr p15, 0, r8, c13, c0, 0 /* FCSE--PID */
+ mcr p15, 0, r9, c13, c0, 1 /* Context-ID */
+
+ mov r0, #0
+ ldmfd sp!, {r0-r12, pc}
+
+SYS_CTRL_BASE_P :
+ .word SYS_CTRL_BASE_PA
+MPMC_BASE_P :
+ .word MPMC_BASE_PA
+MISC_BASE_P :
+ .word MISC_BASE_PA
+SRAM_START_P:
+ .word SPEAR_START_SRAM
+SCRATCH_PAD:
+ .word SPEAR_SRAM_SCR_REG
+DISABLE_I_C_M_V:
+ .word 0x1005
+PLL_VAL1:
+ .word 0x1c0a
+PLL_VAL2:
+ .word 0x1c0e
+PLL_VAL3:
+ .word 0x1c06
+ENTRY(spear_sleep_mode_sz)
+ .word . - spear_sleep_mode
--
1.7.2.2
--
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