* [PATCH v2 1/5] ARM: OMAP2+: Introduce low-level suspend code for AM33XX
2017-05-19 20:04 [PATCH v2 0/5] ARM: OMAP2+: AM33XX/AM43XX: Add suspend-resume support Dave Gerlach
@ 2017-05-19 20:04 ` Dave Gerlach
2017-05-19 20:04 ` [PATCH v2 2/5] ARM: OMAP2+: Introduce low-level suspend code for AM43XX Dave Gerlach
` (3 subsequent siblings)
4 siblings, 0 replies; 15+ messages in thread
From: Dave Gerlach @ 2017-05-19 20:04 UTC (permalink / raw)
To: Tony Lindgren, Santosh Shilimkar, Russell King
Cc: linux-arm-kernel, linux-omap, linux-kernel, Dave Gerlach, Keerthy J
In preparation for suspend-resume support for AM33XX, add
the assembly file with the code which is copied to internal
memory (OCMC RAM) during bootup and runs from there.
As part of the low power entry (DeepSleep0 mode in AM33XX TRM),
the code running from OCMC RAM does the following
1. Calls routine to store the EMIF configuration
2. Calls routine to place external memory in self-refresh
3. Disables EMIF clock
4. Executes WFI after writing to MPU_CLKCTRL register.
If no interrupts have come, WFI execution on MPU gets registered
as an interrupt with the WKUP-M3. WKUP-M3 takes care of disabling
some clocks which MPU should not (L3, L4, OCMC RAM etc) and takes
care of clockdomain and powerdomain transitions as part of the
DeepSleep0 mode entry.
In case a late interrupt comes in, WFI ends up as a NOP and MPU
continues execution from internal memory. The 'abort path' code
undoes whatever was done as part of the low power entry and indicates
a suspend failure by passing a non-zero value to the cpu_resume routine.
The 'resume path' code is similar to the 'abort path' with the key
difference of MMU being enabled in the 'abort path' but being
disabled in the 'resume path' due to MPU getting powered off.
Signed-off-by: Dave Gerlach <d-gerlach@ti.com>
---
arch/arm/mach-omap2/sleep33xx.S | 221 ++++++++++++++++++++++++++++++++++++++++
1 file changed, 221 insertions(+)
create mode 100644 arch/arm/mach-omap2/sleep33xx.S
diff --git a/arch/arm/mach-omap2/sleep33xx.S b/arch/arm/mach-omap2/sleep33xx.S
new file mode 100644
index 000000000000..1141bfb5108f
--- /dev/null
+++ b/arch/arm/mach-omap2/sleep33xx.S
@@ -0,0 +1,221 @@
+/*
+ * Low level suspend code for AM33XX SoCs
+ *
+ * Copyright (C) 2012-2017 Texas Instruments Incorporated - http://www.ti.com/
+ * Dave Gerlach, Vaibhav Bedia
+ *
+ * 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 <linux/ti-emif-sram.h>
+#include <asm/asm-offsets.h>
+#include <asm/assembler.h>
+#include <asm/memory.h>
+
+#include "iomap.h"
+#include "cm33xx.h"
+
+#define AM33XX_CM_CLKCTRL_MODULESTATE_DISABLED 0x00030000
+#define AM33XX_CM_CLKCTRL_MODULEMODE_DISABLE 0x0003
+#define AM33XX_CM_CLKCTRL_MODULEMODE_ENABLE 0x0002
+
+ .arm
+ .align 3
+
+ENTRY(am33xx_do_wfi)
+ stmfd sp!, {r4 - r11, lr} @ save registers on stack
+
+ /*
+ * Flush all data from the L1 and L2 data cache before disabling
+ * SCTLR.C bit.
+ */
+ ldr r1, kernel_flush
+ blx r1
+
+ /*
+ * Clear the SCTLR.C bit to prevent further data cache
+ * allocation. Clearing SCTLR.C would make all the data accesses
+ * strongly ordered and would not hit the cache.
+ */
+ mrc p15, 0, r0, c1, c0, 0
+ bic r0, r0, #(1 << 2) @ Disable the C bit
+ mcr p15, 0, r0, c1, c0, 0
+ isb
+
+ /*
+ * Invalidate L1 and L2 data cache.
+ */
+ ldr r1, kernel_flush
+ blx r1
+
+ adr r9, am33xx_emif_sram_table
+
+ ldr r3, [r9, #EMIF_PM_SAVE_CONTEXT_OFFSET]
+ blx r3
+
+ ldr r3, [r9, #EMIF_PM_ENTER_SR_OFFSET]
+ blx r3
+
+ /* Disable EMIF */
+ ldr r1, virt_emif_clkctrl
+ ldr r2, [r1]
+ bic r2, r2, #AM33XX_CM_CLKCTRL_MODULEMODE_DISABLE
+ str r2, [r1]
+
+ ldr r1, virt_emif_clkctrl
+wait_emif_disable:
+ ldr r2, [r1]
+ mov r3, #AM33XX_CM_CLKCTRL_MODULESTATE_DISABLED
+ cmp r2, r3
+ bne wait_emif_disable
+
+ /*
+ * For the MPU WFI to be registered as an interrupt
+ * to WKUP_M3, MPU_CLKCTRL.MODULEMODE needs to be set
+ * to DISABLED
+ */
+ ldr r1, virt_mpu_clkctrl
+ ldr r2, [r1]
+ bic r2, r2, #AM33XX_CM_CLKCTRL_MODULEMODE_DISABLE
+ str r2, [r1]
+
+ /*
+ * Execute an ISB instruction to ensure that all of the
+ * CP15 register changes have been committed.
+ */
+ isb
+
+ /*
+ * Execute a barrier instruction to ensure that all cache,
+ * TLB and branch predictor maintenance operations issued
+ * have completed.
+ */
+ dsb
+ dmb
+
+ /*
+ * Execute a WFI instruction and wait until the
+ * STANDBYWFI output is asserted to indicate that the
+ * CPU is in idle and low power state. CPU can specualatively
+ * prefetch the instructions so add NOPs after WFI. Thirteen
+ * NOPs as per Cortex-A8 pipeline.
+ */
+ wfi
+
+ nop
+ nop
+ nop
+ nop
+ nop
+ nop
+ nop
+ nop
+ nop
+ nop
+ nop
+ nop
+ nop
+
+ /* We come here in case of an abort due to a late interrupt */
+
+ /* Set MPU_CLKCTRL.MODULEMODE back to ENABLE */
+ ldr r1, virt_mpu_clkctrl
+ mov r2, #AM33XX_CM_CLKCTRL_MODULEMODE_ENABLE
+ str r2, [r1]
+
+ /* Re-enable EMIF */
+ ldr r1, virt_emif_clkctrl
+ mov r2, #AM33XX_CM_CLKCTRL_MODULEMODE_ENABLE
+ str r2, [r1]
+wait_emif_enable:
+ ldr r3, [r1]
+ cmp r2, r3
+ bne wait_emif_enable
+
+
+ ldr r1, [r9, #EMIF_PM_ABORT_SR_OFFSET]
+ blx r1
+
+ /*
+ * Set SCTLR.C bit to allow data cache allocation
+ */
+ mrc p15, 0, r0, c1, c0, 0
+ orr r0, r0, #(1 << 2) @ Enable the C bit
+ mcr p15, 0, r0, c1, c0, 0
+ isb
+
+ /* Let the suspend code know about the abort */
+ mov r0, #1
+ ldmfd sp!, {r4 - r11, pc} @ restore regs and return
+ENDPROC(am33xx_do_wfi)
+
+ .align
+ENTRY(am33xx_resume_offset)
+ .word . - am33xx_do_wfi
+
+ENTRY(am33xx_resume_from_deep_sleep)
+ /* Re-enable EMIF */
+ ldr r0, phys_emif_clkctrl
+ mov r1, #AM33XX_CM_CLKCTRL_MODULEMODE_ENABLE
+ str r1, [r0]
+wait_emif_enable1:
+ ldr r2, [r0]
+ cmp r1, r2
+ bne wait_emif_enable1
+
+ adr r9, am33xx_emif_sram_table
+
+ ldr r1, [r9, #EMIF_PM_RESTORE_CONTEXT_OFFSET]
+ blx r1
+
+ ldr r1, [r9, #EMIF_PM_EXIT_SR_OFFSET]
+ blx r1
+
+resume_to_ddr:
+ /* We are back. Branch to the common CPU resume routine */
+ mov r0, #0
+ ldr pc, resume_addr
+ENDPROC(am33xx_resume_from_deep_sleep)
+
+/*
+ * Local variables
+ */
+ .align
+resume_addr:
+ .word cpu_resume - PAGE_OFFSET + 0x80000000
+kernel_flush:
+ .word v7_flush_dcache_all
+virt_mpu_clkctrl:
+ .word AM33XX_CM_MPU_MPU_CLKCTRL
+virt_emif_clkctrl:
+ .word AM33XX_CM_PER_EMIF_CLKCTRL
+phys_emif_clkctrl:
+ .word (AM33XX_CM_BASE + AM33XX_CM_PER_MOD + \
+ AM33XX_CM_PER_EMIF_CLKCTRL_OFFSET)
+
+.align 3
+/* DDR related defines */
+am33xx_emif_sram_table:
+ .space EMIF_PM_FUNCTIONS_SIZE
+
+ENTRY(am33xx_pm_sram)
+.word am33xx_do_wfi
+.word am33xx_do_wfi_sz
+.word am33xx_resume_offset
+.word am33xx_emif_sram_table
+.word am33xx_pm_ro_sram_data
+
+.align 3
+ENTRY(am33xx_pm_ro_sram_data)
+ .space AMX3_PM_RO_SRAM_DATA_SIZE
+
+ENTRY(am33xx_do_wfi_sz)
+ .word . - am33xx_do_wfi
--
2.13.0
^ permalink raw reply related [flat|nested] 15+ messages in thread* [PATCH v2 2/5] ARM: OMAP2+: Introduce low-level suspend code for AM43XX
2017-05-19 20:04 [PATCH v2 0/5] ARM: OMAP2+: AM33XX/AM43XX: Add suspend-resume support Dave Gerlach
2017-05-19 20:04 ` [PATCH v2 1/5] ARM: OMAP2+: Introduce low-level suspend code for AM33XX Dave Gerlach
@ 2017-05-19 20:04 ` Dave Gerlach
2017-05-19 20:04 ` [PATCH v2 3/5] ARM: OMAP2+: pm33xx-core: Add platform code needed for PM Dave Gerlach
` (2 subsequent siblings)
4 siblings, 0 replies; 15+ messages in thread
From: Dave Gerlach @ 2017-05-19 20:04 UTC (permalink / raw)
To: Tony Lindgren, Santosh Shilimkar, Russell King
Cc: linux-arm-kernel, linux-omap, linux-kernel, Dave Gerlach, Keerthy J
Although similar to AM33XX, introduce a new low-level asm file for
suspend containing new context save and restore paths for EMIF and l2
cache disabling and enabling.
Signed-off-by: Dave Gerlach <d-gerlach@ti.com>
---
arch/arm/mach-omap2/sleep43xx.S | 394 ++++++++++++++++++++++++++++++++++++++++
1 file changed, 394 insertions(+)
create mode 100644 arch/arm/mach-omap2/sleep43xx.S
diff --git a/arch/arm/mach-omap2/sleep43xx.S b/arch/arm/mach-omap2/sleep43xx.S
new file mode 100644
index 000000000000..a3d71b53e936
--- /dev/null
+++ b/arch/arm/mach-omap2/sleep43xx.S
@@ -0,0 +1,394 @@
+/*
+ * Low level suspend code for AM43XX SoCs
+ *
+ * Copyright (C) 2013-2017 Texas Instruments Incorporated - http://www.ti.com/
+ * Dave Gerlach, Vaibhav Bedia
+ *
+ * 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 <linux/ti-emif-sram.h>
+
+#include <asm/asm-offsets.h>
+#include <asm/assembler.h>
+#include <asm/hardware/cache-l2x0.h>
+#include <asm/memory.h>
+
+#include "cm33xx.h"
+#include "common.h"
+#include "iomap.h"
+#include "omap-secure.h"
+#include "omap44xx.h"
+#include "prm33xx.h"
+#include "prcm43xx.h"
+
+#define AM33XX_CM_CLKCTRL_MODULESTATE_DISABLED 0x00030000
+#define AM33XX_CM_CLKCTRL_MODULEMODE_DISABLE 0x0003
+#define AM33XX_CM_CLKCTRL_MODULEMODE_ENABLE 0x0002
+
+#define AM43XX_EMIF_POWEROFF_ENABLE 0x1
+#define AM43XX_EMIF_POWEROFF_DISABLE 0x0
+
+#define AM43XX_CM_CLKSTCTRL_CLKTRCTRL_SW_SLEEP 0x1
+#define AM43XX_CM_CLKSTCTRL_CLKTRCTRL_HW_AUTO 0x3
+
+#define AM43XX_CM_BASE 0x44DF0000
+
+#define AM43XX_CM_REGADDR(inst, reg) \
+ AM33XX_L4_WK_IO_ADDRESS(AM43XX_CM_BASE + (inst) + (reg))
+
+#define AM43XX_CM_MPU_CLKSTCTRL AM43XX_CM_REGADDR(AM43XX_CM_MPU_INST, \
+ AM43XX_CM_MPU_MPU_CDOFFS)
+#define AM43XX_CM_MPU_MPU_CLKCTRL AM43XX_CM_REGADDR(AM43XX_CM_MPU_INST, \
+ AM43XX_CM_MPU_MPU_CLKCTRL_OFFSET)
+#define AM43XX_CM_PER_EMIF_CLKCTRL AM43XX_CM_REGADDR(AM43XX_CM_PER_INST, \
+ AM43XX_CM_PER_EMIF_CLKCTRL_OFFSET)
+#define AM43XX_PRM_EMIF_CTRL_OFFSET 0x0030
+
+ .arm
+ .align 3
+
+ENTRY(am43xx_do_wfi)
+ stmfd sp!, {r4 - r11, lr} @ save registers on stack
+
+ /* Retrieve l2 cache virt address BEFORE we shut off EMIF */
+ ldr r1, get_l2cache_base
+ blx r1
+ mov r8, r0
+
+ /*
+ * Flush all data from the L1 and L2 data cache before disabling
+ * SCTLR.C bit.
+ */
+ ldr r1, kernel_flush
+ blx r1
+
+ /*
+ * Clear the SCTLR.C bit to prevent further data cache
+ * allocation. Clearing SCTLR.C would make all the data accesses
+ * strongly ordered and would not hit the cache.
+ */
+ mrc p15, 0, r0, c1, c0, 0
+ bic r0, r0, #(1 << 2) @ Disable the C bit
+ mcr p15, 0, r0, c1, c0, 0
+ isb
+ dsb
+
+ /*
+ * Invalidate L1 and L2 data cache.
+ */
+ ldr r1, kernel_flush
+ blx r1
+
+#ifdef CONFIG_CACHE_L2X0
+ /*
+ * Clean and invalidate the L2 cache.
+ */
+#ifdef CONFIG_PL310_ERRATA_727915
+ mov r0, #0x03
+ mov r12, #OMAP4_MON_L2X0_DBG_CTRL_INDEX
+ dsb
+ smc #0
+ dsb
+#endif
+ mov r0, r8
+ adr r4, am43xx_pm_ro_sram_data
+ ldr r3, [r4, #AMX3_PM_RO_SRAM_DATA_VIRT_OFFSET]
+
+ mov r2, r0
+ ldr r0, [r2, #L2X0_AUX_CTRL]
+ str r0, [r3, #AMX3_PM_L2_AUX_CTRL_VAL_OFFSET]
+ ldr r0, [r2, #L310_PREFETCH_CTRL]
+ str r0, [r3, #AMX3_PM_L2_PREFETCH_CTRL_VAL_OFFSET]
+
+ ldr r0, l2_val
+ str r0, [r2, #L2X0_CLEAN_INV_WAY]
+wait:
+ ldr r0, [r2, #L2X0_CLEAN_INV_WAY]
+ ldr r1, l2_val
+ ands r0, r0, r1
+ bne wait
+#ifdef CONFIG_PL310_ERRATA_727915
+ mov r0, #0x00
+ mov r12, #OMAP4_MON_L2X0_DBG_CTRL_INDEX
+ dsb
+ smc #0
+ dsb
+#endif
+l2x_sync:
+ mov r0, r8
+ mov r2, r0
+ mov r0, #0x0
+ str r0, [r2, #L2X0_CACHE_SYNC]
+sync:
+ ldr r0, [r2, #L2X0_CACHE_SYNC]
+ ands r0, r0, #0x1
+ bne sync
+#endif
+
+ adr r9, am43xx_emif_sram_table
+
+ ldr r3, [r9, #EMIF_PM_SAVE_CONTEXT_OFFSET]
+ blx r3
+
+ ldr r3, [r9, #EMIF_PM_ENTER_SR_OFFSET]
+ blx r3
+
+ /* Disable EMIF */
+ ldr r1, am43xx_virt_emif_clkctrl
+ ldr r2, [r1]
+ bic r2, r2, #AM33XX_CM_CLKCTRL_MODULEMODE_DISABLE
+ str r2, [r1]
+
+wait_emif_disable:
+ ldr r2, [r1]
+ mov r3, #AM33XX_CM_CLKCTRL_MODULESTATE_DISABLED
+ cmp r2, r3
+ bne wait_emif_disable
+
+ /*
+ * For the MPU WFI to be registered as an interrupt
+ * to WKUP_M3, MPU_CLKCTRL.MODULEMODE needs to be set
+ * to DISABLED
+ */
+ ldr r1, am43xx_virt_mpu_clkctrl
+ ldr r2, [r1]
+ bic r2, r2, #AM33XX_CM_CLKCTRL_MODULEMODE_DISABLE
+ str r2, [r1]
+
+ /*
+ * Put MPU CLKDM to SW_SLEEP
+ */
+ ldr r1, am43xx_virt_mpu_clkstctrl
+ mov r2, #AM43XX_CM_CLKSTCTRL_CLKTRCTRL_SW_SLEEP
+ str r2, [r1]
+
+ /*
+ * Execute a barrier instruction to ensure that all cache,
+ * TLB and branch predictor maintenance operations issued
+ * have completed.
+ */
+ dsb
+ dmb
+
+ /*
+ * Execute a WFI instruction and wait until the
+ * STANDBYWFI output is asserted to indicate that the
+ * CPU is in idle and low power state. CPU can specualatively
+ * prefetch the instructions so add NOPs after WFI. Sixteen
+ * NOPs as per Cortex-A9 pipeline.
+ */
+ wfi
+
+ nop
+ nop
+ nop
+ nop
+ nop
+ nop
+ nop
+ nop
+ nop
+ nop
+ nop
+ nop
+ nop
+ nop
+ nop
+ nop
+
+ /* We come here in case of an abort due to a late interrupt */
+ ldr r1, am43xx_virt_mpu_clkstctrl
+ mov r2, #AM43XX_CM_CLKSTCTRL_CLKTRCTRL_HW_AUTO
+ str r2, [r1]
+
+ /* Set MPU_CLKCTRL.MODULEMODE back to ENABLE */
+ ldr r1, am43xx_virt_mpu_clkctrl
+ mov r2, #AM33XX_CM_CLKCTRL_MODULEMODE_ENABLE
+ str r2, [r1]
+
+ /* Re-enable EMIF */
+ ldr r1, am43xx_virt_emif_clkctrl
+ mov r2, #AM33XX_CM_CLKCTRL_MODULEMODE_ENABLE
+ str r2, [r1]
+wait_emif_enable:
+ ldr r3, [r1]
+ cmp r2, r3
+ bne wait_emif_enable
+
+ /*
+ * Set SCTLR.C bit to allow data cache allocation
+ */
+ mrc p15, 0, r0, c1, c0, 0
+ orr r0, r0, #(1 << 2) @ Enable the C bit
+ mcr p15, 0, r0, c1, c0, 0
+ isb
+
+ ldr r1, [r9, #EMIF_PM_ABORT_SR_OFFSET]
+ blx r1
+
+ /* Let the suspend code know about the abort */
+ mov r0, #1
+ ldmfd sp!, {r4 - r11, pc} @ restore regs and return
+ENDPROC(am43xx_do_wfi)
+
+ .align
+ENTRY(am43xx_resume_offset)
+ .word . - am43xx_do_wfi
+
+ENTRY(am43xx_resume_from_deep_sleep)
+ /* Set MPU CLKSTCTRL to HW AUTO so that CPUidle works properly */
+ ldr r1, am43xx_virt_mpu_clkstctrl
+ mov r2, #AM43XX_CM_CLKSTCTRL_CLKTRCTRL_HW_AUTO
+ str r2, [r1]
+
+ /* For AM43xx, use EMIF power down until context is restored */
+ ldr r2, am43xx_phys_emif_poweroff
+ mov r1, #AM43XX_EMIF_POWEROFF_ENABLE
+ str r1, [r2, #0x0]
+
+ /* Re-enable EMIF */
+ ldr r1, am43xx_phys_emif_clkctrl
+ mov r2, #AM33XX_CM_CLKCTRL_MODULEMODE_ENABLE
+ str r2, [r1]
+wait_emif_enable1:
+ ldr r3, [r1]
+ cmp r2, r3
+ bne wait_emif_enable1
+
+ adr r9, am43xx_emif_sram_table
+
+ ldr r1, [r9, #EMIF_PM_RESTORE_CONTEXT_OFFSET]
+ blx r1
+
+ ldr r1, [r9, #EMIF_PM_EXIT_SR_OFFSET]
+ blx r1
+
+ ldr r2, am43xx_phys_emif_poweroff
+ mov r1, #AM43XX_EMIF_POWEROFF_DISABLE
+ str r1, [r2, #0x0]
+
+#ifdef CONFIG_CACHE_L2X0
+ ldr r2, l2_cache_base
+ ldr r0, [r2, #L2X0_CTRL]
+ and r0, #0x0f
+ cmp r0, #1
+ beq skip_l2en @ Skip if already enabled
+
+ adr r4, am43xx_pm_ro_sram_data
+ ldr r3, [r4, #AMX3_PM_RO_SRAM_DATA_PHYS_OFFSET]
+ ldr r0, [r3, #AMX3_PM_L2_PREFETCH_CTRL_VAL_OFFSET]
+
+ ldr r12, l2_smc1
+ dsb
+ smc #0
+ dsb
+set_aux_ctrl:
+ ldr r0, [r3, #AMX3_PM_L2_AUX_CTRL_VAL_OFFSET]
+ ldr r12, l2_smc2
+ dsb
+ smc #0
+ dsb
+
+ /* L2 invalidate on resume */
+ ldr r0, l2_val
+ ldr r2, l2_cache_base
+ str r0, [r2, #L2X0_INV_WAY]
+wait2:
+ ldr r0, [r2, #L2X0_INV_WAY]
+ ldr r1, l2_val
+ ands r0, r0, r1
+ bne wait2
+#ifdef CONFIG_PL310_ERRATA_727915
+ mov r0, #0x00
+ mov r12, #OMAP4_MON_L2X0_DBG_CTRL_INDEX
+ dsb
+ smc #0
+ dsb
+#endif
+l2x_sync2:
+ ldr r2, l2_cache_base
+ mov r0, #0x0
+ str r0, [r2, #L2X0_CACHE_SYNC]
+sync2:
+ ldr r0, [r2, #L2X0_CACHE_SYNC]
+ ands r0, r0, #0x1
+ bne sync2
+
+ mov r0, #0x1
+ ldr r12, l2_smc3
+ dsb
+ smc #0
+ dsb
+#endif
+skip_l2en:
+ /* We are back. Branch to the common CPU resume routine */
+ mov r0, #0
+ ldr pc, resume_addr
+ENDPROC(am43xx_resume_from_deep_sleep)
+
+/*
+ * Local variables
+ */
+ .align
+resume_addr:
+ .word cpu_resume - PAGE_OFFSET + 0x80000000
+get_l2cache_base:
+ .word omap4_get_l2cache_base
+kernel_flush:
+ .word v7_flush_dcache_all
+ddr_start:
+ .word PAGE_OFFSET
+
+am43xx_phys_emif_poweroff:
+ .word (AM43XX_CM_BASE + AM43XX_PRM_DEVICE_INST + \
+ AM43XX_PRM_EMIF_CTRL_OFFSET)
+am43xx_virt_mpu_clkstctrl:
+ .word (AM43XX_CM_MPU_CLKSTCTRL)
+am43xx_virt_mpu_clkctrl:
+ .word (AM43XX_CM_MPU_MPU_CLKCTRL)
+am43xx_virt_emif_clkctrl:
+ .word (AM43XX_CM_PER_EMIF_CLKCTRL)
+am43xx_phys_emif_clkctrl:
+ .word (AM43XX_CM_BASE + AM43XX_CM_PER_INST + \
+ AM43XX_CM_PER_EMIF_CLKCTRL_OFFSET)
+
+/* L2 cache related defines for AM437x */
+l2_cache_base:
+ .word OMAP44XX_L2CACHE_BASE
+l2_smc1:
+ .word OMAP4_MON_L2X0_PREFETCH_INDEX
+l2_smc2:
+ .word OMAP4_MON_L2X0_AUXCTRL_INDEX
+l2_smc3:
+ .word OMAP4_MON_L2X0_CTRL_INDEX
+l2_val:
+ .word 0xffff
+
+.align 3
+/* DDR related defines */
+ENTRY(am43xx_emif_sram_table)
+ .space EMIF_PM_FUNCTIONS_SIZE
+
+ENTRY(am43xx_pm_sram)
+.word am43xx_do_wfi
+.word am43xx_do_wfi_sz
+.word am43xx_resume_offset
+.word am43xx_emif_sram_table
+.word am43xx_pm_ro_sram_data
+
+.align 3
+
+ENTRY(am43xx_pm_ro_sram_data)
+ .space AMX3_PM_RO_SRAM_DATA_SIZE
+
+ENTRY(am43xx_do_wfi_sz)
+ .word . - am43xx_do_wfi
--
2.13.0
^ permalink raw reply related [flat|nested] 15+ messages in thread* [PATCH v2 3/5] ARM: OMAP2+: pm33xx-core: Add platform code needed for PM
2017-05-19 20:04 [PATCH v2 0/5] ARM: OMAP2+: AM33XX/AM43XX: Add suspend-resume support Dave Gerlach
2017-05-19 20:04 ` [PATCH v2 1/5] ARM: OMAP2+: Introduce low-level suspend code for AM33XX Dave Gerlach
2017-05-19 20:04 ` [PATCH v2 2/5] ARM: OMAP2+: Introduce low-level suspend code for AM43XX Dave Gerlach
@ 2017-05-19 20:04 ` Dave Gerlach
2017-05-22 14:56 ` Tony Lindgren
2017-07-04 13:14 ` Johan Hovold
2017-05-19 20:04 ` [PATCH v2 4/5] soc: ti: Add pm33xx driver for basic suspend support Dave Gerlach
2017-05-19 20:04 ` [PATCH v2 5/5] ARM: OMAP2+: Create dummy platform_device for pm33xx Dave Gerlach
4 siblings, 2 replies; 15+ messages in thread
From: Dave Gerlach @ 2017-05-19 20:04 UTC (permalink / raw)
To: Tony Lindgren, Santosh Shilimkar, Russell King
Cc: linux-arm-kernel, linux-omap, linux-kernel, Dave Gerlach, Keerthy J
Most of the PM code needed for am335x and am437x can be moved into a
module under drivers but some core code must remain in mach-omap2 at the
moment. This includes some internal clockdomain APIs and low-level ARM
APIs which are also not exported for use by modules.
Implement a few functions that handle these low-level platform
operations can be passed to the pm33xx module through the use of
platform data.
In addition to this, to be able to share data structures between C and
the sleep33xx and sleep43xx assembly code, we can automatically generate
all of the C struct member offsets and sizes as macros by making use of
the ARM asm-offsets file. In the same header that we define our data
structures in we also define all the macros in an inline function and by
adding a call to this in the asm_offsets file all macros are properly
generated and available to the assembly code without cluttering up the
asm-offsets file.
Signed-off-by: Dave Gerlach <d-gerlach@ti.com>
---
arch/arm/kernel/asm-offsets.c | 2 +
arch/arm/mach-omap2/Kconfig | 1 +
arch/arm/mach-omap2/Makefile | 4 +
arch/arm/mach-omap2/pm.h | 5 +
arch/arm/mach-omap2/pm33xx-core.c | 181 +++++++++++++++++++++++++++++++++++
include/linux/platform_data/pm33xx.h | 69 +++++++++++++
6 files changed, 262 insertions(+)
create mode 100644 arch/arm/mach-omap2/pm33xx-core.c
create mode 100644 include/linux/platform_data/pm33xx.h
diff --git a/arch/arm/kernel/asm-offsets.c b/arch/arm/kernel/asm-offsets.c
index d728b5660e36..62253e7bfac4 100644
--- a/arch/arm/kernel/asm-offsets.c
+++ b/arch/arm/kernel/asm-offsets.c
@@ -28,6 +28,7 @@
#include <asm/vdso_datapage.h>
#include <asm/hardware/cache-l2x0.h>
#include <linux/kbuild.h>
+#include <linux/platform_data/pm33xx.h>
#include <linux/ti-emif-sram.h>
/*
@@ -187,6 +188,7 @@ int main(void)
#if defined(CONFIG_SOC_AM33XX) || defined(CONFIG_SOC_AM43XX)
BLANK();
ti_emif_offsets();
+ amx3_pm_asm_offsets();
#endif
return 0;
diff --git a/arch/arm/mach-omap2/Kconfig b/arch/arm/mach-omap2/Kconfig
index 0465338183c7..940173fa0992 100644
--- a/arch/arm/mach-omap2/Kconfig
+++ b/arch/arm/mach-omap2/Kconfig
@@ -72,6 +72,7 @@ config SOC_AM43XX
select ARM_ERRATA_754322
select ARM_ERRATA_775420
select OMAP_INTERCONNECT
+ select ARM_CPU_SUSPEND if PM
config SOC_DRA7XX
bool "TI DRA7XX"
diff --git a/arch/arm/mach-omap2/Makefile b/arch/arm/mach-omap2/Makefile
index c89757abb0ae..8475ae3f9ff1 100644
--- a/arch/arm/mach-omap2/Makefile
+++ b/arch/arm/mach-omap2/Makefile
@@ -88,6 +88,8 @@ omap-4-5-pm-common += pm44xx.o
obj-$(CONFIG_ARCH_OMAP4) += $(omap-4-5-pm-common)
obj-$(CONFIG_SOC_OMAP5) += $(omap-4-5-pm-common)
obj-$(CONFIG_SOC_DRA7XX) += $(omap-4-5-pm-common)
+obj-$(CONFIG_SOC_AM33XX) += pm33xx-core.o sleep33xx.o
+obj-$(CONFIG_SOC_AM43XX) += pm33xx-core.o sleep43xx.o
obj-$(CONFIG_PM_DEBUG) += pm-debug.o
obj-$(CONFIG_POWER_AVS_OMAP) += sr_device.o
@@ -95,6 +97,8 @@ obj-$(CONFIG_POWER_AVS_OMAP_CLASS3) += smartreflex-class3.o
AFLAGS_sleep24xx.o :=-Wa,-march=armv6
AFLAGS_sleep34xx.o :=-Wa,-march=armv7-a$(plus_sec)
+AFLAGS_sleep33xx.o :=-Wa,-march=armv7-a$(plus_sec)
+AFLAGS_sleep43xx.o :=-Wa,-march=armv7-a$(plus_sec)
endif
diff --git a/arch/arm/mach-omap2/pm.h b/arch/arm/mach-omap2/pm.h
index b668719b9b25..2f9649b89053 100644
--- a/arch/arm/mach-omap2/pm.h
+++ b/arch/arm/mach-omap2/pm.h
@@ -81,6 +81,11 @@ extern unsigned int omap3_do_wfi_sz;
/* ... and its pointer from SRAM after copy */
extern void (*omap3_do_wfi_sram)(void);
+struct am33xx_pm_platform_data *am33xx_pm_get_pdata(void);
+
+extern struct am33xx_pm_sram_addr am33xx_pm_sram;
+extern struct am33xx_pm_sram_addr am43xx_pm_sram;
+
/* save_secure_ram_context function pointer and size, for copy to SRAM */
extern int save_secure_ram_context(u32 *addr);
extern unsigned int save_secure_ram_context_sz;
diff --git a/arch/arm/mach-omap2/pm33xx-core.c b/arch/arm/mach-omap2/pm33xx-core.c
new file mode 100644
index 000000000000..c84ffc4de2e9
--- /dev/null
+++ b/arch/arm/mach-omap2/pm33xx-core.c
@@ -0,0 +1,181 @@
+/*
+ * AM33XX Arch Power Management Routines
+ *
+ * Copyright (C) 2016-2017 Texas Instruments Incorporated - http://www.ti.com/
+ * Dave Gerlach
+ *
+ * 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 <asm/smp_scu.h>
+#include <asm/suspend.h>
+#include <linux/platform_data/pm33xx.h>
+
+#include "cm33xx.h"
+#include "common.h"
+#include "control.h"
+#include "clockdomain.h"
+#include "iomap.h"
+#include "omap_hwmod.h"
+#include "pm.h"
+#include "powerdomain.h"
+#include "prm33xx.h"
+#include "soc.h"
+#include "sram.h"
+
+static struct powerdomain *cefuse_pwrdm, *gfx_pwrdm, *per_pwrdm, *mpu_pwrdm;
+static struct clockdomain *gfx_l4ls_clkdm;
+static void __iomem *scu_base;
+
+static int __init am43xx_map_scu(void)
+{
+ scu_base = ioremap(scu_a9_get_base(), SZ_256);
+
+ if (!scu_base)
+ return -ENOMEM;
+
+ return 0;
+}
+
+static int amx3_common_init(void)
+{
+ gfx_pwrdm = pwrdm_lookup("gfx_pwrdm");
+ per_pwrdm = pwrdm_lookup("per_pwrdm");
+ mpu_pwrdm = pwrdm_lookup("mpu_pwrdm");
+
+ if ((!gfx_pwrdm) || (!per_pwrdm) || (!mpu_pwrdm))
+ return -ENODEV;
+
+ (void)clkdm_for_each(omap_pm_clkdms_setup, NULL);
+
+ /* CEFUSE domain can be turned off post bootup */
+ cefuse_pwrdm = pwrdm_lookup("cefuse_pwrdm");
+ if (cefuse_pwrdm)
+ omap_set_pwrdm_state(cefuse_pwrdm, PWRDM_POWER_OFF);
+ else
+ pr_err("PM: Failed to get cefuse_pwrdm\n");
+
+ return 0;
+}
+
+static int am33xx_suspend_init(void)
+{
+ int ret;
+
+ gfx_l4ls_clkdm = clkdm_lookup("gfx_l4ls_gfx_clkdm");
+
+ if (!gfx_l4ls_clkdm) {
+ pr_err("PM: Cannot lookup gfx_l4ls_clkdm clockdomains\n");
+ return -ENODEV;
+ }
+
+ ret = amx3_common_init();
+
+ return ret;
+}
+
+static int am43xx_suspend_init(void)
+{
+ int ret = 0;
+
+ ret = am43xx_map_scu();
+ if (ret) {
+ pr_err("PM: Could not ioremap SCU\n");
+ return ret;
+ }
+
+ ret = amx3_common_init();
+
+ return ret;
+}
+
+static void amx3_pre_suspend_common(void)
+{
+ omap_set_pwrdm_state(gfx_pwrdm, PWRDM_POWER_OFF);
+}
+
+static void amx3_post_suspend_common(void)
+{
+ int status;
+ /*
+ * Because gfx_pwrdm is the only one under MPU control,
+ * comment on transition status
+ */
+ status = pwrdm_read_pwrst(gfx_pwrdm);
+ if (status != PWRDM_POWER_OFF)
+ pr_err("PM: GFX domain did not transition: %x\n", status);
+}
+
+static int am33xx_suspend(unsigned int state, int (*fn)(unsigned long))
+{
+ int ret = 0;
+
+ amx3_pre_suspend_common();
+ ret = cpu_suspend(0, fn);
+ amx3_post_suspend_common();
+
+ /*
+ * BUG: GFX_L4LS clock domain needs to be woken up to
+ * ensure thet L4LS clock domain does not get stuck in
+ * transition. If that happens L3 module does not get
+ * disabled, thereby leading to PER power domain
+ * transition failing
+ */
+
+ clkdm_wakeup(gfx_l4ls_clkdm);
+ clkdm_sleep(gfx_l4ls_clkdm);
+
+ return ret;
+}
+
+static int am43xx_suspend(unsigned int state, int (*fn)(unsigned long))
+{
+ int ret = 0;
+
+ amx3_pre_suspend_common();
+ scu_power_mode(scu_base, SCU_PM_POWEROFF);
+ ret = cpu_suspend(0, fn);
+ scu_power_mode(scu_base, SCU_PM_NORMAL);
+ amx3_post_suspend_common();
+
+ return ret;
+}
+
+static struct am33xx_pm_sram_addr *amx3_get_sram_addrs(void)
+{
+ if (soc_is_am33xx())
+ return &am33xx_pm_sram;
+ else if (soc_is_am437x())
+ return &am43xx_pm_sram;
+ else
+ return NULL;
+}
+
+static struct am33xx_pm_platform_data am33xx_ops = {
+ .init = am33xx_suspend_init,
+ .soc_suspend = am33xx_suspend,
+ .get_sram_addrs = amx3_get_sram_addrs,
+};
+
+static struct am33xx_pm_platform_data am43xx_ops = {
+ .init = am43xx_suspend_init,
+ .soc_suspend = am43xx_suspend,
+ .get_sram_addrs = amx3_get_sram_addrs,
+};
+
+struct am33xx_pm_platform_data *am33xx_pm_get_pdata(void)
+{
+ if (soc_is_am33xx())
+ return &am33xx_ops;
+ else if (soc_is_am437x())
+ return &am43xx_ops;
+ else
+ return NULL;
+}
diff --git a/include/linux/platform_data/pm33xx.h b/include/linux/platform_data/pm33xx.h
new file mode 100644
index 000000000000..c191ab681093
--- /dev/null
+++ b/include/linux/platform_data/pm33xx.h
@@ -0,0 +1,69 @@
+/*
+ * TI pm33xx platform data
+ *
+ * Copyright (C) 2016-2017 Texas Instruments, Inc.
+ * Dave Gerlach <d-gerlach@ti.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#ifndef _LINUX_PLATFORM_DATA_PM33XX_H
+#define _LINUX_PLATFORM_DATA_PM33XX_H
+
+#include <linux/kbuild.h>
+
+#ifndef __ASSEMBLER__
+struct am33xx_pm_sram_addr {
+ void (*do_wfi)(void);
+ unsigned long *do_wfi_sz;
+ unsigned long *resume_offset;
+ unsigned long *emif_sram_table;
+ unsigned long *ro_sram_data;
+};
+
+struct am33xx_pm_platform_data {
+ int (*init)(void);
+ int (*soc_suspend)(unsigned int state, int (*fn)(unsigned long));
+ struct am33xx_pm_sram_addr *(*get_sram_addrs)(void);
+};
+
+struct am33xx_pm_sram_data {
+ u32 wfi_flags;
+ u32 l2_aux_ctrl_val;
+ u32 l2_prefetch_ctrl_val;
+};
+
+struct am33xx_pm_ro_sram_data {
+ u32 amx3_pm_sram_data_virt;
+ u32 amx3_pm_sram_data_phys;
+};
+
+extern inline void amx3_pm_asm_offsets(void)
+{
+ DEFINE(AMX3_PM_WFI_FLAGS_OFFSET,
+ offsetof(struct am33xx_pm_sram_data, wfi_flags));
+ DEFINE(AMX3_PM_L2_AUX_CTRL_VAL_OFFSET,
+ offsetof(struct am33xx_pm_sram_data, l2_aux_ctrl_val));
+ DEFINE(AMX3_PM_L2_PREFETCH_CTRL_VAL_OFFSET,
+ offsetof(struct am33xx_pm_sram_data, l2_prefetch_ctrl_val));
+ DEFINE(AMX3_PM_SRAM_DATA_SIZE, sizeof(struct am33xx_pm_sram_data));
+
+ BLANK();
+
+ DEFINE(AMX3_PM_RO_SRAM_DATA_VIRT_OFFSET,
+ offsetof(struct am33xx_pm_ro_sram_data, amx3_pm_sram_data_virt));
+ DEFINE(AMX3_PM_RO_SRAM_DATA_PHYS_OFFSET,
+ offsetof(struct am33xx_pm_ro_sram_data, amx3_pm_sram_data_phys));
+ DEFINE(AMX3_PM_RO_SRAM_DATA_SIZE,
+ sizeof(struct am33xx_pm_ro_sram_data));
+}
+
+#endif /* __ASSEMBLER__ */
+#endif /* _LINUX_PLATFORM_DATA_PM33XX_H */
--
2.13.0
^ permalink raw reply related [flat|nested] 15+ messages in thread* Re: [PATCH v2 3/5] ARM: OMAP2+: pm33xx-core: Add platform code needed for PM
2017-05-19 20:04 ` [PATCH v2 3/5] ARM: OMAP2+: pm33xx-core: Add platform code needed for PM Dave Gerlach
@ 2017-05-22 14:56 ` Tony Lindgren
2017-07-04 13:14 ` Johan Hovold
1 sibling, 0 replies; 15+ messages in thread
From: Tony Lindgren @ 2017-05-22 14:56 UTC (permalink / raw)
To: Russell King
Cc: Santosh Shilimkar, Russell King, linux-arm-kernel, linux-omap,
linux-kernel, Keerthy J, Dave Gerlach
Hi,
* Dave Gerlach <d-gerlach@ti.com> [170519 13:08]:
> In addition to this, to be able to share data structures between C and
> the sleep33xx and sleep43xx assembly code, we can automatically generate
> all of the C struct member offsets and sizes as macros by making use of
> the ARM asm-offsets file. In the same header that we define our data
> structures in we also define all the macros in an inline function and by
> adding a call to this in the asm_offsets file all macros are properly
> generated and available to the assembly code without cluttering up the
> asm-offsets file.
...
> diff --git a/arch/arm/kernel/asm-offsets.c b/arch/arm/kernel/asm-offsets.c
> index d728b5660e36..62253e7bfac4 100644
> --- a/arch/arm/kernel/asm-offsets.c
> +++ b/arch/arm/kernel/asm-offsets.c
> @@ -28,6 +28,7 @@
> #include <asm/vdso_datapage.h>
> #include <asm/hardware/cache-l2x0.h>
> #include <linux/kbuild.h>
> +#include <linux/platform_data/pm33xx.h>
> #include <linux/ti-emif-sram.h>
>
> /*
> @@ -187,6 +188,7 @@ int main(void)
> #if defined(CONFIG_SOC_AM33XX) || defined(CONFIG_SOC_AM43XX)
> BLANK();
> ti_emif_offsets();
> + amx3_pm_asm_offsets();
> #endif
>
> return 0;
Russell, care to take a look at the above if you're OK with it or
if you prefer to do it some other way?
Also please see thread "[PATCH v2 0/2] memory: Introduce ti-emif-sram
driver" for similar changes.
Thanks,
Tony
^ permalink raw reply [flat|nested] 15+ messages in thread
* Re: [PATCH v2 3/5] ARM: OMAP2+: pm33xx-core: Add platform code needed for PM
2017-05-19 20:04 ` [PATCH v2 3/5] ARM: OMAP2+: pm33xx-core: Add platform code needed for PM Dave Gerlach
2017-05-22 14:56 ` Tony Lindgren
@ 2017-07-04 13:14 ` Johan Hovold
2017-07-06 19:02 ` Dave Gerlach
1 sibling, 1 reply; 15+ messages in thread
From: Johan Hovold @ 2017-07-04 13:14 UTC (permalink / raw)
To: Dave Gerlach
Cc: Tony Lindgren, Santosh Shilimkar, Russell King, linux-arm-kernel,
linux-omap, linux-kernel, Keerthy J
On Fri, May 19, 2017 at 03:04:36PM -0500, Dave Gerlach wrote:
> Most of the PM code needed for am335x and am437x can be moved into a
> module under drivers but some core code must remain in mach-omap2 at the
> moment. This includes some internal clockdomain APIs and low-level ARM
> APIs which are also not exported for use by modules.
>
> Implement a few functions that handle these low-level platform
> operations can be passed to the pm33xx module through the use of
> platform data.
>
> In addition to this, to be able to share data structures between C and
> the sleep33xx and sleep43xx assembly code, we can automatically generate
> all of the C struct member offsets and sizes as macros by making use of
> the ARM asm-offsets file. In the same header that we define our data
> structures in we also define all the macros in an inline function and by
> adding a call to this in the asm_offsets file all macros are properly
> generated and available to the assembly code without cluttering up the
> asm-offsets file.
>
> Signed-off-by: Dave Gerlach <d-gerlach@ti.com>
> ---
> diff --git a/arch/arm/mach-omap2/pm.h b/arch/arm/mach-omap2/pm.h
> index b668719b9b25..2f9649b89053 100644
> --- a/arch/arm/mach-omap2/pm.h
> +++ b/arch/arm/mach-omap2/pm.h
> @@ -81,6 +81,11 @@ extern unsigned int omap3_do_wfi_sz;
> /* ... and its pointer from SRAM after copy */
> extern void (*omap3_do_wfi_sram)(void);
>
> +struct am33xx_pm_platform_data *am33xx_pm_get_pdata(void);
This one is not used outside of pm33xx-core.c so can now be static, and
this declaration can be dropped.
> diff --git a/arch/arm/mach-omap2/pm33xx-core.c b/arch/arm/mach-omap2/pm33xx-core.c
> new file mode 100644
> index 000000000000..c84ffc4de2e9
> --- /dev/null
> +++ b/arch/arm/mach-omap2/pm33xx-core.c
> @@ -0,0 +1,181 @@
> +/*
> + * AM33XX Arch Power Management Routines
> + *
> + * Copyright (C) 2016-2017 Texas Instruments Incorporated - http://www.ti.com/
> + * Dave Gerlach
> + *
> + * 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 <asm/smp_scu.h>
I get a compilation error here when compiling for am335x without
CONFIG_HAVE_ARM_SCU due to a missing errno.h include:
In file included from /home/johan/work/omicron/src/linux/arch/arm/mach-omap2/pm33xx-core.c:17:0:
/home/johan/work/omicron/src/linux/arch/arm/include/asm/smp_scu.h: In function 'scu_power_mode':
/home/johan/work/omicron/src/linux/arch/arm/include/asm/smp_scu.h:36:10: error: 'EINVAL' undeclared (first use in this function)
return -EINVAL;
^
/home/johan/work/omicron/src/linux/arch/arm/include/asm/smp_scu.h:36:10: note: each undeclared identifier is reported only once for each function it appears in
This is arguably a bug in the header, which I'm submitting a fix for,
but you should include errno.h above anyway as you use its definitions
below as well.
> +#include <asm/suspend.h>
> +#include <linux/platform_data/pm33xx.h>
<snip>
> diff --git a/include/linux/platform_data/pm33xx.h b/include/linux/platform_data/pm33xx.h
> new file mode 100644
> index 000000000000..c191ab681093
> --- /dev/null
> +++ b/include/linux/platform_data/pm33xx.h
> @@ -0,0 +1,69 @@
> +/*
> + * TI pm33xx platform data
> + *
> + * Copyright (C) 2016-2017 Texas Instruments, Inc.
> + * Dave Gerlach <d-gerlach@ti.com>
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
> + * GNU General Public License for more details.
> + */
> +
> +#ifndef _LINUX_PLATFORM_DATA_PM33XX_H
> +#define _LINUX_PLATFORM_DATA_PM33XX_H
> +
And here you should add a linux/types.h include to make this header
self-contained. Right now you are depending on the scu header to pull in
the types for pm33xx-core.c above.
> +#include <linux/kbuild.h>
> +
> +#ifndef __ASSEMBLER__
> +struct am33xx_pm_sram_addr {
> + void (*do_wfi)(void);
> + unsigned long *do_wfi_sz;
> + unsigned long *resume_offset;
> + unsigned long *emif_sram_table;
> + unsigned long *ro_sram_data;
> +};
> +
> +struct am33xx_pm_platform_data {
> + int (*init)(void);
> + int (*soc_suspend)(unsigned int state, int (*fn)(unsigned long));
> + struct am33xx_pm_sram_addr *(*get_sram_addrs)(void);
> +};
> +
> +struct am33xx_pm_sram_data {
> + u32 wfi_flags;
> + u32 l2_aux_ctrl_val;
> + u32 l2_prefetch_ctrl_val;
> +};
> +
> +struct am33xx_pm_ro_sram_data {
> + u32 amx3_pm_sram_data_virt;
> + u32 amx3_pm_sram_data_phys;
> +};
Johan
^ permalink raw reply [flat|nested] 15+ messages in thread* Re: [PATCH v2 3/5] ARM: OMAP2+: pm33xx-core: Add platform code needed for PM
2017-07-04 13:14 ` Johan Hovold
@ 2017-07-06 19:02 ` Dave Gerlach
0 siblings, 0 replies; 15+ messages in thread
From: Dave Gerlach @ 2017-07-06 19:02 UTC (permalink / raw)
To: Johan Hovold
Cc: Tony Lindgren, Santosh Shilimkar, Russell King, linux-arm-kernel,
linux-omap, linux-kernel, Keerthy J
On 07/04/2017 08:14 AM, Johan Hovold wrote:
> On Fri, May 19, 2017 at 03:04:36PM -0500, Dave Gerlach wrote:
>> Most of the PM code needed for am335x and am437x can be moved into a
>> module under drivers but some core code must remain in mach-omap2 at the
>> moment. This includes some internal clockdomain APIs and low-level ARM
>> APIs which are also not exported for use by modules.
>>
>> Implement a few functions that handle these low-level platform
>> operations can be passed to the pm33xx module through the use of
>> platform data.
>>
>> In addition to this, to be able to share data structures between C and
>> the sleep33xx and sleep43xx assembly code, we can automatically generate
>> all of the C struct member offsets and sizes as macros by making use of
>> the ARM asm-offsets file. In the same header that we define our data
>> structures in we also define all the macros in an inline function and by
>> adding a call to this in the asm_offsets file all macros are properly
>> generated and available to the assembly code without cluttering up the
>> asm-offsets file.
>>
>> Signed-off-by: Dave Gerlach <d-gerlach@ti.com>
>> ---
>
>> diff --git a/arch/arm/mach-omap2/pm.h b/arch/arm/mach-omap2/pm.h
>> index b668719b9b25..2f9649b89053 100644
>> --- a/arch/arm/mach-omap2/pm.h
>> +++ b/arch/arm/mach-omap2/pm.h
>> @@ -81,6 +81,11 @@ extern unsigned int omap3_do_wfi_sz;
>> /* ... and its pointer from SRAM after copy */
>> extern void (*omap3_do_wfi_sram)(void);
>>
>> +struct am33xx_pm_platform_data *am33xx_pm_get_pdata(void);
>
> This one is not used outside of pm33xx-core.c so can now be static, and
> this declaration can be dropped.
Yes you are correct, seems I missed this in a refactor.
>
>> diff --git a/arch/arm/mach-omap2/pm33xx-core.c b/arch/arm/mach-omap2/pm33xx-core.c
>> new file mode 100644
>> index 000000000000..c84ffc4de2e9
>> --- /dev/null
>> +++ b/arch/arm/mach-omap2/pm33xx-core.c
>> @@ -0,0 +1,181 @@
>> +/*
>> + * AM33XX Arch Power Management Routines
>> + *
>> + * Copyright (C) 2016-2017 Texas Instruments Incorporated - http://www.ti.com/
>> + * Dave Gerlach
>> + *
>> + * 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 <asm/smp_scu.h>
>
> I get a compilation error here when compiling for am335x without
> CONFIG_HAVE_ARM_SCU due to a missing errno.h include:
>
> In file included from /home/johan/work/omicron/src/linux/arch/arm/mach-omap2/pm33xx-core.c:17:0:
> /home/johan/work/omicron/src/linux/arch/arm/include/asm/smp_scu.h: In function 'scu_power_mode':
> /home/johan/work/omicron/src/linux/arch/arm/include/asm/smp_scu.h:36:10: error: 'EINVAL' undeclared (first use in this function)
> return -EINVAL;
> ^
> /home/johan/work/omicron/src/linux/arch/arm/include/asm/smp_scu.h:36:10: note: each undeclared identifier is reported only once for each function it appears in
>
> This is arguably a bug in the header, which I'm submitting a fix for,
> but you should include errno.h above anyway as you use its definitions
> below as well.
>
Yes ok, good catch.
>> +#include <asm/suspend.h>
>> +#include <linux/platform_data/pm33xx.h>
>
> <snip>
>
>> diff --git a/include/linux/platform_data/pm33xx.h b/include/linux/platform_data/pm33xx.h
>> new file mode 100644
>> index 000000000000..c191ab681093
>> --- /dev/null
>> +++ b/include/linux/platform_data/pm33xx.h
>> @@ -0,0 +1,69 @@
>> +/*
>> + * TI pm33xx platform data
>> + *
>> + * Copyright (C) 2016-2017 Texas Instruments, Inc.
>> + * Dave Gerlach <d-gerlach@ti.com>
>> + *
>> + * This program is free software; you can redistribute it and/or modify
>> + * it under the terms of the GNU General Public License version 2 as
>> + * published by the Free Software Foundation.
>> + *
>> + * This program is distributed in the hope that it will be useful,
>> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
>> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
>> + * GNU General Public License for more details.
>> + */
>> +
>> +#ifndef _LINUX_PLATFORM_DATA_PM33XX_H
>> +#define _LINUX_PLATFORM_DATA_PM33XX_H
>> +
>
> And here you should add a linux/types.h include to make this header
> self-contained. Right now you are depending on the scu header to pull in
> the types for pm33xx-core.c above.
>
Ok will do. Thanks for the comments.
Regards,
Dave
>> +#include <linux/kbuild.h>
>> +
>> +#ifndef __ASSEMBLER__
>> +struct am33xx_pm_sram_addr {
>> + void (*do_wfi)(void);
>> + unsigned long *do_wfi_sz;
>> + unsigned long *resume_offset;
>> + unsigned long *emif_sram_table;
>> + unsigned long *ro_sram_data;
>> +};
>> +
>> +struct am33xx_pm_platform_data {
>> + int (*init)(void);
>> + int (*soc_suspend)(unsigned int state, int (*fn)(unsigned long));
>> + struct am33xx_pm_sram_addr *(*get_sram_addrs)(void);
>> +};
>> +
>> +struct am33xx_pm_sram_data {
>> + u32 wfi_flags;
>> + u32 l2_aux_ctrl_val;
>> + u32 l2_prefetch_ctrl_val;
>> +};
>> +
>> +struct am33xx_pm_ro_sram_data {
>> + u32 amx3_pm_sram_data_virt;
>> + u32 amx3_pm_sram_data_phys;
>> +};
>
> Johan
>
^ permalink raw reply [flat|nested] 15+ messages in thread
* [PATCH v2 4/5] soc: ti: Add pm33xx driver for basic suspend support
2017-05-19 20:04 [PATCH v2 0/5] ARM: OMAP2+: AM33XX/AM43XX: Add suspend-resume support Dave Gerlach
` (2 preceding siblings ...)
2017-05-19 20:04 ` [PATCH v2 3/5] ARM: OMAP2+: pm33xx-core: Add platform code needed for PM Dave Gerlach
@ 2017-05-19 20:04 ` Dave Gerlach
2017-07-03 16:54 ` Johan Hovold
2017-05-19 20:04 ` [PATCH v2 5/5] ARM: OMAP2+: Create dummy platform_device for pm33xx Dave Gerlach
4 siblings, 1 reply; 15+ messages in thread
From: Dave Gerlach @ 2017-05-19 20:04 UTC (permalink / raw)
To: Tony Lindgren, Santosh Shilimkar, Russell King
Cc: linux-arm-kernel, linux-omap, linux-kernel, Dave Gerlach, Keerthy J
AM335x and AM437x support various low power modes as documented
in section 8.1.4.3 of the AM335x Technical Reference Manual and
section 6.4.3 of the AM437x Technical Reference Manual.
DeepSleep0 mode offers the lowest power mode with limited
wakeup sources without a system reboot and is mapped as
the suspend state in the kernel. In this state, MPU and
PER domains are turned off with the internal RAM held in
retention to facilitate the resume process. As part of
the boot process, the assembly code is copied over to OCMCRAM
so it can be executed to turn of the EMIF and put DDR into self
refresh.
Both platforms have a Cortex-M3 (WKUP_M3) which assists the MPU
in DeepSleep0 entry and exit. WKUP_M3 takes care
of the clockdomain and powerdomain transitions based on the
intended low power state. MPU needs to load the appropriate
WKUP_M3 binary onto the WKUP_M3 memory space before it can
leverage any of the PM features like DeepSleep. This loading
is handled by the remoteproc driver wkup_m3_rproc.
Communication with the WKUP_M3 is handled by a wkup_m3_ipc
driver that exposes the specific PM functionality to be used
the PM code.
In the current implementation when the suspend process
is initiated, MPU interrupts the WKUP_M3 to let it know about
the intent of entering DeepSleep0 and waits for an ACK. When
the ACK is received MPU continues with its suspend process
to suspend all the drivers and then jumps to assembly in
OCMC RAM. The assembly code puts the external RAM in self-refresh
mode, gates the MPU clock, and then finally executes the WFI
instruction. Execution of the WFI instruction with MPU clock gated
triggers another interrupt to the WKUP_M3 which then continues
with the power down sequence wherein the clockdomain and
powerdomain transition takes place. As part of the sleep sequence,
WKUP_M3 unmasks the interrupt lines for the wakeup sources. WFI
execution on WKUP_M3 causes the hardware to disable the main
oscillator of the SoC and from here system remains in sleep state
until a wake source brings the system into resume path.
When a wakeup event occurs, WKUP_M3 starts the power-up
sequence by switching on the power domains and finally
enabling the clock to MPU. Since the MPU gets powered down
as part of the sleep sequence in the resume path ROM code
starts executing. The ROM code detects a wakeup from sleep
and then jumps to the resume location in OCMC which was
populated in one of the IPC registers as part of the suspend
sequence.
Code is based on work by Vaibhav Bedia.
Signed-off-by: Dave Gerlach <d-gerlach@ti.com>
---
drivers/soc/ti/Kconfig | 9 +
drivers/soc/ti/Makefile | 1 +
drivers/soc/ti/pm33xx.c | 337 +++++++++++++++++++++++++++++++++++
include/linux/platform_data/pm33xx.h | 4 +-
4 files changed, 349 insertions(+), 2 deletions(-)
create mode 100644 drivers/soc/ti/pm33xx.c
diff --git a/drivers/soc/ti/Kconfig b/drivers/soc/ti/Kconfig
index 39e152abe6b9..92770d84a288 100644
--- a/drivers/soc/ti/Kconfig
+++ b/drivers/soc/ti/Kconfig
@@ -28,6 +28,15 @@ config KEYSTONE_NAVIGATOR_DMA
If unsure, say N.
+config AMX3_PM
+ tristate "AMx3 Power Management"
+ depends on SOC_AM33XX || SOC_AM43XX
+ depends on WKUP_M3_IPC && TI_EMIF_SRAM && SRAM
+ help
+ Enable power management on AM335x and AM437x. Required for suspend to mem
+ and standby states on both AM335x and AM437x platforms and for deeper cpuidle
+ c-states on AM335x.
+
config WKUP_M3_IPC
tristate "TI AMx3 Wkup-M3 IPC Driver"
depends on WKUP_M3_RPROC
diff --git a/drivers/soc/ti/Makefile b/drivers/soc/ti/Makefile
index 7d572736c86e..d9bd4ba424be 100644
--- a/drivers/soc/ti/Makefile
+++ b/drivers/soc/ti/Makefile
@@ -4,5 +4,6 @@
obj-$(CONFIG_KEYSTONE_NAVIGATOR_QMSS) += knav_qmss.o
knav_qmss-y := knav_qmss_queue.o knav_qmss_acc.o
obj-$(CONFIG_KEYSTONE_NAVIGATOR_DMA) += knav_dma.o
+obj-$(CONFIG_AMX3_PM) += pm33xx.o
obj-$(CONFIG_WKUP_M3_IPC) += wkup_m3_ipc.o
obj-$(CONFIG_TI_SCI_PM_DOMAINS) += ti_sci_pm_domains.o
diff --git a/drivers/soc/ti/pm33xx.c b/drivers/soc/ti/pm33xx.c
new file mode 100644
index 000000000000..cfeb8df7e82a
--- /dev/null
+++ b/drivers/soc/ti/pm33xx.c
@@ -0,0 +1,337 @@
+/*
+ * AM33XX Power Management Routines
+ *
+ * Copyright (C) 2012-2017 Texas Instruments Incorporated - http://www.ti.com/
+ * Vaibhav Bedia, Dave Gerlach
+ *
+ * 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/cpu.h>
+#include <linux/err.h>
+#include <linux/genalloc.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_data/pm33xx.h>
+#include <linux/platform_device.h>
+#include <linux/sizes.h>
+#include <linux/sram.h>
+#include <linux/suspend.h>
+#include <linux/ti-emif-sram.h>
+#include <linux/wkup_m3_ipc.h>
+
+#include <asm/proc-fns.h>
+#include <asm/suspend.h>
+#include <asm/system_misc.h>
+
+#define AMX3_PM_SRAM_SYMBOL_OFFSET(sym) ((unsigned long)(sym) - \
+ (unsigned long)pm_sram->do_wfi)
+
+static int (*am33xx_do_wfi_sram)(unsigned long unused);
+static phys_addr_t am33xx_do_wfi_sram_phys;
+
+static struct gen_pool *sram_pool, *sram_pool_data;
+static unsigned long ocmcram_location, ocmcram_location_data;
+
+static struct am33xx_pm_platform_data *pm_ops;
+static struct am33xx_pm_sram_addr *pm_sram;
+
+static struct wkup_m3_ipc *m3_ipc;
+
+static u32 sram_suspend_address(unsigned long addr)
+{
+ return ((unsigned long)am33xx_do_wfi_sram +
+ AMX3_PM_SRAM_SYMBOL_OFFSET(addr));
+}
+
+#ifdef CONFIG_SUSPEND
+static int am33xx_pm_suspend(suspend_state_t suspend_state)
+{
+ int i, ret = 0;
+
+ ret = pm_ops->soc_suspend((unsigned long)suspend_state,
+ am33xx_do_wfi_sram);
+
+ if (ret) {
+ pr_err("PM: Kernel suspend failure\n");
+ } else {
+ i = m3_ipc->ops->request_pm_status(m3_ipc);
+
+ switch (i) {
+ case 0:
+ pr_info("PM: Successfully put all powerdomains to target state\n");
+ break;
+ case 1:
+ pr_err("PM: Could not transition all powerdomains to target state\n");
+ ret = -1;
+ break;
+ default:
+ pr_err("PM: CM3 returned unknown result = %d\n", i);
+ ret = -1;
+ }
+ }
+
+ return ret;
+}
+
+static int am33xx_pm_enter(suspend_state_t suspend_state)
+{
+ int ret = 0;
+
+ switch (suspend_state) {
+ case PM_SUSPEND_MEM:
+ case PM_SUSPEND_STANDBY:
+ ret = am33xx_pm_suspend(suspend_state);
+ break;
+ default:
+ ret = -EINVAL;
+ }
+
+ return ret;
+}
+
+static int am33xx_pm_begin(suspend_state_t state)
+{
+ int ret = -EINVAL;
+
+ switch (state) {
+ case PM_SUSPEND_MEM:
+ ret = m3_ipc->ops->prepare_low_power(m3_ipc, WKUP_M3_DEEPSLEEP);
+ break;
+ case PM_SUSPEND_STANDBY:
+ ret = m3_ipc->ops->prepare_low_power(m3_ipc, WKUP_M3_STANDBY);
+ break;
+ }
+
+ return ret;
+}
+
+static void am33xx_pm_end(void)
+{
+ m3_ipc->ops->finish_low_power(m3_ipc);
+}
+
+static int am33xx_pm_valid(suspend_state_t state)
+{
+ switch (state) {
+ case PM_SUSPEND_STANDBY:
+ case PM_SUSPEND_MEM:
+ return 1;
+ default:
+ return 0;
+ }
+}
+
+static const struct platform_suspend_ops am33xx_pm_ops = {
+ .begin = am33xx_pm_begin,
+ .end = am33xx_pm_end,
+ .enter = am33xx_pm_enter,
+ .valid = am33xx_pm_valid,
+};
+#endif /* CONFIG_SUSPEND */
+
+static void am33xx_pm_set_ipc_ops(void)
+{
+ u32 resume_address;
+ int temp;
+
+ temp = ti_emif_get_mem_type();
+ if (temp < 0) {
+ pr_err("PM: Cannot determine memory type, no PM available\n");
+ return;
+ }
+ m3_ipc->ops->set_mem_type(m3_ipc, temp);
+
+ /* Physical resume address to be used by ROM code */
+ resume_address = am33xx_do_wfi_sram_phys +
+ *pm_sram->resume_offset + 0x4;
+
+ m3_ipc->ops->set_resume_address(m3_ipc, (void *)resume_address);
+}
+
+static void am33xx_pm_free_sram(void)
+{
+ gen_pool_free(sram_pool, ocmcram_location, *pm_sram->do_wfi_sz);
+ gen_pool_free(sram_pool_data, ocmcram_location_data,
+ sizeof(struct am33xx_pm_ro_sram_data));
+}
+
+/*
+ * Push the minimal suspend-resume code to SRAM
+ */
+static int am33xx_prepare_push_sram_idle(void)
+{
+ struct device_node *np;
+
+ np = of_find_compatible_node(NULL, NULL, "ti,omap3-mpu");
+
+ if (!np) {
+ np = of_find_compatible_node(NULL, NULL, "ti,omap4-mpu");
+ if (!np) {
+ pr_warn("PM: %s: Unable to find device node for mpu\n",
+ __func__);
+ return -ENODEV;
+ }
+ }
+
+ sram_pool = of_gen_pool_get(np, "pm-sram", 0);
+ if (!sram_pool) {
+ pr_warn("PM: %s: Unable to get sram pool for ocmcram\n",
+ __func__);
+ return -ENODEV;
+ }
+
+ sram_pool_data = of_gen_pool_get(np, "pm-sram", 1);
+ if (!sram_pool_data) {
+ pr_warn("PM: %s: Unable to get sram data pool for ocmcram\n",
+ __func__);
+ return -ENODEV;
+ }
+
+ ocmcram_location = gen_pool_alloc(sram_pool, *pm_sram->do_wfi_sz);
+ if (!ocmcram_location) {
+ pr_warn("PM: %s: Unable to allocate memory from ocmcram\n",
+ __func__);
+ return -ENOMEM;
+ }
+
+ ocmcram_location_data = gen_pool_alloc(sram_pool_data,
+ sizeof(struct emif_regs_amx3));
+ if (!ocmcram_location_data) {
+ pr_err("PM: Unable to allocate memory from ocmcram\n");
+ gen_pool_free(sram_pool, ocmcram_location, *pm_sram->do_wfi_sz);
+ return -ENOMEM;
+ }
+
+ return 0;
+}
+
+static int am33xx_push_sram_idle(void)
+{
+ struct am33xx_pm_ro_sram_data ro_sram_data;
+ int ret;
+ void *copy_addr;
+
+ ro_sram_data.amx3_pm_sram_data_virt = ocmcram_location_data;
+ ro_sram_data.amx3_pm_sram_data_phys =
+ gen_pool_virt_to_phys(sram_pool_data, ocmcram_location_data);
+
+ /* Save physical address to calculate resume offset during pm init */
+ am33xx_do_wfi_sram_phys = gen_pool_virt_to_phys(sram_pool,
+ ocmcram_location);
+
+ am33xx_do_wfi_sram = sram_exec_copy(sram_pool, (void *)ocmcram_location,
+ pm_sram->do_wfi,
+ *pm_sram->do_wfi_sz);
+ if (!am33xx_do_wfi_sram) {
+ pr_err("PM: %s: am33xx_do_wfi copy to sram failed\n", __func__);
+ return -ENODEV;
+ }
+
+ ret = ti_emif_copy_pm_function_table(sram_pool,
+ (void *)sram_suspend_address((unsigned long)pm_sram->emif_sram_table));
+ if (ret) {
+ pr_warn("PM: %s: EMIF function copy failed\n", __func__);
+ return -EPROBE_DEFER;
+ }
+
+ copy_addr = sram_exec_copy(sram_pool,
+ (void *)sram_suspend_address((unsigned long)pm_sram->ro_sram_data),
+ &ro_sram_data,
+ sizeof(ro_sram_data));
+ if (!copy_addr) {
+ pr_err("PM: %s: ro_sram_data copy to sram failed\n", __func__);
+ return -ENODEV;
+ }
+
+ return 0;
+}
+
+static int am33xx_pm_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ int ret;
+
+ if (!of_machine_is_compatible("ti,am33xx") &&
+ !of_machine_is_compatible("ti,am43"))
+ return -ENODEV;
+
+ pm_ops = dev->platform_data;
+ if (!pm_ops) {
+ pr_err("PM: Cannot get core PM ops!\n");
+ return -ENODEV;
+ }
+
+ pm_sram = pm_ops->get_sram_addrs();
+ if (!pm_sram) {
+ pr_err("PM: Cannot get PM asm function addresses!!\n");
+ return -ENODEV;
+ }
+
+ ret = am33xx_prepare_push_sram_idle();
+ if (ret)
+ return ret;
+
+ ret = am33xx_push_sram_idle();
+ if (ret)
+ goto err_free_sram;
+
+ m3_ipc = wkup_m3_ipc_get();
+ if (!m3_ipc) {
+ pr_err("PM: Cannot get wkup_m3_ipc handle\n");
+ ret = -EPROBE_DEFER;
+ goto err_free_sram;
+ }
+
+ am33xx_pm_set_ipc_ops();
+
+#ifdef CONFIG_SUSPEND
+ suspend_set_ops(&am33xx_pm_ops);
+#endif /* CONFIG_SUSPEND */
+
+ ret = pm_ops->init();
+ if (ret) {
+ pr_err("Unable to call core pm init!\n");
+ ret = -ENODEV;
+ goto err_put_wkup_m3_ipc;
+ }
+
+ return 0;
+
+err_put_wkup_m3_ipc:
+ wkup_m3_ipc_put(m3_ipc);
+err_free_sram:
+ am33xx_pm_free_sram();
+ return ret;
+}
+
+static int am33xx_pm_remove(struct platform_device *pdev)
+{
+ suspend_set_ops(NULL);
+ wkup_m3_ipc_put(m3_ipc);
+ am33xx_pm_free_sram();
+ return 0;
+}
+
+static struct platform_driver am33xx_pm_driver = {
+ .driver = {
+ .name = "pm33xx",
+ },
+ .probe = am33xx_pm_probe,
+ .remove = am33xx_pm_remove,
+};
+module_platform_driver(am33xx_pm_driver);
+
+MODULE_ALIAS("platform:pm33xx");
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("am33xx power management driver");
diff --git a/include/linux/platform_data/pm33xx.h b/include/linux/platform_data/pm33xx.h
index c191ab681093..b8d6c3a9b46c 100644
--- a/include/linux/platform_data/pm33xx.h
+++ b/include/linux/platform_data/pm33xx.h
@@ -38,12 +38,12 @@ struct am33xx_pm_sram_data {
u32 wfi_flags;
u32 l2_aux_ctrl_val;
u32 l2_prefetch_ctrl_val;
-};
+} __packed __aligned(8);
struct am33xx_pm_ro_sram_data {
u32 amx3_pm_sram_data_virt;
u32 amx3_pm_sram_data_phys;
-};
+} __packed __aligned(8);
extern inline void amx3_pm_asm_offsets(void)
{
--
2.13.0
^ permalink raw reply related [flat|nested] 15+ messages in thread* Re: [PATCH v2 4/5] soc: ti: Add pm33xx driver for basic suspend support
2017-05-19 20:04 ` [PATCH v2 4/5] soc: ti: Add pm33xx driver for basic suspend support Dave Gerlach
@ 2017-07-03 16:54 ` Johan Hovold
2017-07-04 13:46 ` Johan Hovold
2017-07-06 19:08 ` Dave Gerlach
0 siblings, 2 replies; 15+ messages in thread
From: Johan Hovold @ 2017-07-03 16:54 UTC (permalink / raw)
To: Dave Gerlach
Cc: Tony Lindgren, Santosh Shilimkar, Russell King, linux-arm-kernel,
linux-omap, linux-kernel, Keerthy J
On Fri, May 19, 2017 at 03:04:37PM -0500, Dave Gerlach wrote:
> AM335x and AM437x support various low power modes as documented
> in section 8.1.4.3 of the AM335x Technical Reference Manual and
> section 6.4.3 of the AM437x Technical Reference Manual.
>
> DeepSleep0 mode offers the lowest power mode with limited
> wakeup sources without a system reboot and is mapped as
> the suspend state in the kernel. In this state, MPU and
> PER domains are turned off with the internal RAM held in
> retention to facilitate the resume process. As part of
> the boot process, the assembly code is copied over to OCMCRAM
> so it can be executed to turn of the EMIF and put DDR into self
> refresh.
>
> Both platforms have a Cortex-M3 (WKUP_M3) which assists the MPU
> in DeepSleep0 entry and exit. WKUP_M3 takes care
> of the clockdomain and powerdomain transitions based on the
> intended low power state. MPU needs to load the appropriate
> WKUP_M3 binary onto the WKUP_M3 memory space before it can
> leverage any of the PM features like DeepSleep. This loading
> is handled by the remoteproc driver wkup_m3_rproc.
>
> Communication with the WKUP_M3 is handled by a wkup_m3_ipc
> driver that exposes the specific PM functionality to be used
> the PM code.
> +static void am33xx_pm_free_sram(void)
> +{
> + gen_pool_free(sram_pool, ocmcram_location, *pm_sram->do_wfi_sz);
> + gen_pool_free(sram_pool_data, ocmcram_location_data,
> + sizeof(struct am33xx_pm_ro_sram_data));
> +}
> +
> +/*
> + * Push the minimal suspend-resume code to SRAM
> + */
> +static int am33xx_prepare_push_sram_idle(void)
> +{
> + struct device_node *np;
> +
> + np = of_find_compatible_node(NULL, NULL, "ti,omap3-mpu");
> +
Stray newline.
> + if (!np) {
> + np = of_find_compatible_node(NULL, NULL, "ti,omap4-mpu");
> + if (!np) {
> + pr_warn("PM: %s: Unable to find device node for mpu\n",
> + __func__);
> + return -ENODEV;
> + }
> + }
You never put the reference to np you acquire here.
[snip]
> +static int am33xx_push_sram_idle(void)
> +{
> + struct am33xx_pm_ro_sram_data ro_sram_data;
> + int ret;
> + void *copy_addr;
> +
> + ro_sram_data.amx3_pm_sram_data_virt = ocmcram_location_data;
> + ro_sram_data.amx3_pm_sram_data_phys =
> + gen_pool_virt_to_phys(sram_pool_data, ocmcram_location_data);
> +
> + /* Save physical address to calculate resume offset during pm init */
> + am33xx_do_wfi_sram_phys = gen_pool_virt_to_phys(sram_pool,
> + ocmcram_location);
> +
> + am33xx_do_wfi_sram = sram_exec_copy(sram_pool, (void *)ocmcram_location,
> + pm_sram->do_wfi,
> + *pm_sram->do_wfi_sz);
> + if (!am33xx_do_wfi_sram) {
> + pr_err("PM: %s: am33xx_do_wfi copy to sram failed\n", __func__);
> + return -ENODEV;
> + }
> +
> + ret = ti_emif_copy_pm_function_table(sram_pool,
> + (void *)sram_suspend_address((unsigned long)pm_sram->emif_sram_table));
> + if (ret) {
> + pr_warn("PM: %s: EMIF function copy failed\n", __func__);
> + return -EPROBE_DEFER;
> + }
Here's the dependency to the emif device I commented on earlier (and
below).
> +
> + copy_addr = sram_exec_copy(sram_pool,
> + (void *)sram_suspend_address((unsigned long)pm_sram->ro_sram_data),
> + &ro_sram_data,
> + sizeof(ro_sram_data));
> + if (!copy_addr) {
> + pr_err("PM: %s: ro_sram_data copy to sram failed\n", __func__);
> + return -ENODEV;
> + }
> +
> + return 0;
> +}
> +
> +static int am33xx_pm_probe(struct platform_device *pdev)
> +{
> + struct device *dev = &pdev->dev;
> + int ret;
> +
> + if (!of_machine_is_compatible("ti,am33xx") &&
> + !of_machine_is_compatible("ti,am43"))
> + return -ENODEV;
> +
> + pm_ops = dev->platform_data;
> + if (!pm_ops) {
> + pr_err("PM: Cannot get core PM ops!\n");
> + return -ENODEV;
> + }
> +
> + pm_sram = pm_ops->get_sram_addrs();
> + if (!pm_sram) {
> + pr_err("PM: Cannot get PM asm function addresses!!\n");
> + return -ENODEV;
> + }
> +
> + ret = am33xx_prepare_push_sram_idle();
Perhaps calling this one am33xx_pm_alloc_sram() would be more
descriptive (and match the release function)?
> + if (ret)
> + return ret;
> +
> + ret = am33xx_push_sram_idle();
> + if (ret)
> + goto err_free_sram;
As I mentioned in my comments to the emif-sram driver, you may need to
create device link to the emif-sram device to prevent it from going away
under you here.
> +
> + m3_ipc = wkup_m3_ipc_get();
> + if (!m3_ipc) {
> + pr_err("PM: Cannot get wkup_m3_ipc handle\n");
You shouldn't log this as an error when probe is being deferred.
Why not use dev_err and friends for logging now that you have a struct
device?
And similarly to the emif-sram device, you may need to create a
device-link also to the ipc device to prevent its driver from being
unbound.
> + ret = -EPROBE_DEFER;
> + goto err_free_sram;
> + }
> +
> + am33xx_pm_set_ipc_ops();
> +
> +#ifdef CONFIG_SUSPEND
> + suspend_set_ops(&am33xx_pm_ops);
> +#endif /* CONFIG_SUSPEND */
This renders a lockdep splash about a circular locking dependency when
suspending since we're taking the pm_mutex in suspend_set_ops here, and
during suspend we flush any deferred probes while already holding the
mutex:
======================================================
WARNING: possible circular locking dependency detected
4.12.0-rc7 #11 Not tainted
------------------------------------------------------
bash/404 is trying to acquire lock:
(deferred_probe_work){+.+.+.}, at: [<c014cf3c>] flush_work+0x30/0x27c
but task is already holding lock:
(pm_mutex){+.+...}, at: [<c01792dc>] pm_suspend+0x190/0xc94
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #1 (pm_mutex){+.+...}:
__mutex_lock+0x80/0x694
mutex_lock_nested+0x2c/0x34
suspend_set_ops+0x4c/0x128
am33xx_pm_probe+0x1fc/0x3a8
platform_drv_probe+0x5c/0xc0
driver_probe_device+0x37c/0x490
__device_attach_driver+0xac/0x128
bus_for_each_drv+0x74/0xa8
__device_attach+0xc4/0x154
device_initial_probe+0x1c/0x20
bus_probe_device+0x98/0xa0
deferred_probe_work_func+0x4c/0xe4
process_one_work+0x1f4/0x758
worker_thread+0x1e0/0x514
kthread+0x128/0x158
ret_from_fork+0x14/0x24
-> #0 (deferred_probe_work){+.+.+.}:
lock_acquire+0x108/0x264
flush_work+0x60/0x27c
wait_for_device_probe+0x24/0xa4
dpm_prepare+0xd0/0x91c
dpm_suspend_start+0x1c/0x70
suspend_devices_and_enter+0xc4/0xeac
pm_suspend+0x890/0xc94
state_store+0x80/0xdc
kobj_attr_store+0x1c/0x28
sysfs_kf_write+0x5c/0x60
kernfs_fop_write+0x128/0x254
__vfs_write+0x38/0x128
vfs_write+0xb4/0x174
SyS_write+0x54/0xb0
ret_fast_syscall+0x0/0x1c
Johan
^ permalink raw reply [flat|nested] 15+ messages in thread* Re: [PATCH v2 4/5] soc: ti: Add pm33xx driver for basic suspend support
2017-07-03 16:54 ` Johan Hovold
@ 2017-07-04 13:46 ` Johan Hovold
2017-07-06 19:08 ` Dave Gerlach
1 sibling, 0 replies; 15+ messages in thread
From: Johan Hovold @ 2017-07-04 13:46 UTC (permalink / raw)
To: Dave Gerlach
Cc: Tony Lindgren, Santosh Shilimkar, Russell King, linux-arm-kernel,
linux-omap, linux-kernel, Keerthy J
On Mon, Jul 03, 2017 at 06:54:19PM +0200, Johan Hovold wrote:
> On Fri, May 19, 2017 at 03:04:37PM -0500, Dave Gerlach wrote:
> > +static int am33xx_pm_probe(struct platform_device *pdev)
> > +#ifdef CONFIG_SUSPEND
> > + suspend_set_ops(&am33xx_pm_ops);
> > +#endif /* CONFIG_SUSPEND */
>
> This renders a lockdep splash about a circular locking dependency when
> suspending since we're taking the pm_mutex in suspend_set_ops here, and
> during suspend we flush any deferred probes while already holding the
> mutex:
Here's the full splat against 4.12:
======================================================
WARNING: possible circular locking dependency detected
4.12.0 #30 Not tainted
------------------------------------------------------
bash/404 is trying to acquire lock:
(deferred_probe_work){+.+.+.}, at: [<c014cf3c>] flush_work+0x30/0x27c
but task is already holding lock:
(pm_mutex){+.+...}, at: [<c01792dc>] pm_suspend+0x190/0xc94
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #1 (pm_mutex){+.+...}:
__mutex_lock+0x80/0x694
mutex_lock_nested+0x2c/0x34
suspend_set_ops+0x4c/0x128
am33xx_pm_probe+0x1fc/0x3a8
platform_drv_probe+0x5c/0xc0
driver_probe_device+0x37c/0x490
__device_attach_driver+0xac/0x128
bus_for_each_drv+0x74/0xa8
__device_attach+0xc4/0x154
device_initial_probe+0x1c/0x20
bus_probe_device+0x98/0xa0
deferred_probe_work_func+0x4c/0xe4
process_one_work+0x1f4/0x758
worker_thread+0x1e0/0x514
kthread+0x128/0x158
ret_from_fork+0x14/0x24
-> #0 (deferred_probe_work){+.+.+.}:
lock_acquire+0x108/0x264
flush_work+0x60/0x27c
wait_for_device_probe+0x24/0xa4
dpm_prepare+0xd0/0x91c
dpm_suspend_start+0x1c/0x70
suspend_devices_and_enter+0xc4/0xeac
pm_suspend+0x890/0xc94
state_store+0x80/0xdc
kobj_attr_store+0x1c/0x28
sysfs_kf_write+0x5c/0x60
kernfs_fop_write+0x128/0x254
__vfs_write+0x38/0x128
vfs_write+0xb4/0x174
SyS_write+0x54/0xb0
ret_fast_syscall+0x0/0x1c
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(pm_mutex);
lock(deferred_probe_work);
lock(pm_mutex);
lock(deferred_probe_work);
*** DEADLOCK ***
4 locks held by bash/404:
#0: (sb_writers#6){.+.+.+}, at: [<c0244fac>] vfs_write+0x160/0x174
#1: (&of->mutex){+.+.+.}, at: [<c02bab64>] kernfs_fop_write+0xe4/0x254
#2: (s_active#99){.+.+.+}, at: [<c02bab6c>] kernfs_fop_write+0xec/0x254
#3: (pm_mutex){+.+...}, at: [<c01792dc>] pm_suspend+0x190/0xc94
stack backtrace:
CPU: 0 PID: 404 Comm: bash Not tainted 4.12.0 #30
Hardware name: Generic AM33XX (Flattened Device Tree)
[<c011192c>] (unwind_backtrace) from [<c010e104>] (show_stack+0x20/0x24)
[<c010e104>] (show_stack) from [<c03f2da0>] (dump_stack+0x24/0x28)
[<c03f2da0>] (dump_stack) from [<c016e070>] (print_circular_bug+0x20c/0x334)
[<c016e070>] (print_circular_bug) from [<c0171660>] (__lock_acquire+0x1bf4/0x1c08)
[<c0171660>] (__lock_acquire) from [<c0172000>] (lock_acquire+0x108/0x264)
[<c0172000>] (lock_acquire) from [<c014cf6c>] (flush_work+0x60/0x27c)
[<c014cf6c>] (flush_work) from [<c04a7524>] (wait_for_device_probe+0x24/0xa4)
[<c04a7524>] (wait_for_device_probe) from [<c04bae20>] (dpm_prepare+0xd0/0x91c)
[<c04bae20>] (dpm_prepare) from [<c04bb688>] (dpm_suspend_start+0x1c/0x70)
[<c04bb688>] (dpm_suspend_start) from [<c0178364>] (suspend_devices_and_enter+0xc4/0xeac)
[<c0178364>] (suspend_devices_and_enter) from [<c01799dc>] (pm_suspend+0x890/0xc94)
[<c01799dc>] (pm_suspend) from [<c01773f0>] (state_store+0x80/0xdc)
[<c01773f0>] (state_store) from [<c03f442c>] (kobj_attr_store+0x1c/0x28)
[<c03f442c>] (kobj_attr_store) from [<c02bb858>] (sysfs_kf_write+0x5c/0x60)
[<c02bb858>] (sysfs_kf_write) from [<c02baba8>] (kernfs_fop_write+0x128/0x254)
[<c02baba8>] (kernfs_fop_write) from [<c0243830>] (__vfs_write+0x38/0x128)
[<c0243830>] (__vfs_write) from [<c0244f00>] (vfs_write+0xb4/0x174)
[<c0244f00>] (vfs_write) from [<c0245e08>] (SyS_write+0x54/0xb0)
[<c0245e08>] (SyS_write) from [<c01092e0>] (ret_fast_syscall+0x0/0x1c)
Johan
^ permalink raw reply [flat|nested] 15+ messages in thread* Re: [PATCH v2 4/5] soc: ti: Add pm33xx driver for basic suspend support
2017-07-03 16:54 ` Johan Hovold
2017-07-04 13:46 ` Johan Hovold
@ 2017-07-06 19:08 ` Dave Gerlach
2017-07-10 11:46 ` Johan Hovold
1 sibling, 1 reply; 15+ messages in thread
From: Dave Gerlach @ 2017-07-06 19:08 UTC (permalink / raw)
To: Johan Hovold
Cc: Tony Lindgren, Santosh Shilimkar, Russell King, linux-arm-kernel,
linux-omap, linux-kernel, Keerthy J
On 07/03/2017 11:54 AM, Johan Hovold wrote:
> On Fri, May 19, 2017 at 03:04:37PM -0500, Dave Gerlach wrote:
>> AM335x and AM437x support various low power modes as documented
>> in section 8.1.4.3 of the AM335x Technical Reference Manual and
>> section 6.4.3 of the AM437x Technical Reference Manual.
>>
>> DeepSleep0 mode offers the lowest power mode with limited
>> wakeup sources without a system reboot and is mapped as
>> the suspend state in the kernel. In this state, MPU and
>> PER domains are turned off with the internal RAM held in
>> retention to facilitate the resume process. As part of
>> the boot process, the assembly code is copied over to OCMCRAM
>> so it can be executed to turn of the EMIF and put DDR into self
>> refresh.
>>
>> Both platforms have a Cortex-M3 (WKUP_M3) which assists the MPU
>> in DeepSleep0 entry and exit. WKUP_M3 takes care
>> of the clockdomain and powerdomain transitions based on the
>> intended low power state. MPU needs to load the appropriate
>> WKUP_M3 binary onto the WKUP_M3 memory space before it can
>> leverage any of the PM features like DeepSleep. This loading
>> is handled by the remoteproc driver wkup_m3_rproc.
>>
>> Communication with the WKUP_M3 is handled by a wkup_m3_ipc
>> driver that exposes the specific PM functionality to be used
>> the PM code.
>
>> +static void am33xx_pm_free_sram(void)
>> +{
>> + gen_pool_free(sram_pool, ocmcram_location, *pm_sram->do_wfi_sz);
>> + gen_pool_free(sram_pool_data, ocmcram_location_data,
>> + sizeof(struct am33xx_pm_ro_sram_data));
>> +}
>> +
>> +/*
>> + * Push the minimal suspend-resume code to SRAM
>> + */
>> +static int am33xx_prepare_push_sram_idle(void)
>> +{
>> + struct device_node *np;
>> +
>> + np = of_find_compatible_node(NULL, NULL, "ti,omap3-mpu");
>> +
>
> Stray newline.
>
Yes thanks.
>> + if (!np) {
>> + np = of_find_compatible_node(NULL, NULL, "ti,omap4-mpu");
>> + if (!np) {
>> + pr_warn("PM: %s: Unable to find device node for mpu\n",
>> + __func__);
>> + return -ENODEV;
>> + }
>> + }
>
> You never put the reference to np you acquire here.
Whoops, it seems I did not, will fix.
>
> [snip]
>
>> +static int am33xx_push_sram_idle(void)
>> +{
>> + struct am33xx_pm_ro_sram_data ro_sram_data;
>> + int ret;
>> + void *copy_addr;
>> +
>> + ro_sram_data.amx3_pm_sram_data_virt = ocmcram_location_data;
>> + ro_sram_data.amx3_pm_sram_data_phys =
>> + gen_pool_virt_to_phys(sram_pool_data, ocmcram_location_data);
>> +
>> + /* Save physical address to calculate resume offset during pm init */
>> + am33xx_do_wfi_sram_phys = gen_pool_virt_to_phys(sram_pool,
>> + ocmcram_location);
>> +
>> + am33xx_do_wfi_sram = sram_exec_copy(sram_pool, (void *)ocmcram_location,
>> + pm_sram->do_wfi,
>> + *pm_sram->do_wfi_sz);
>> + if (!am33xx_do_wfi_sram) {
>> + pr_err("PM: %s: am33xx_do_wfi copy to sram failed\n", __func__);
>> + return -ENODEV;
>> + }
>> +
>> + ret = ti_emif_copy_pm_function_table(sram_pool,
>> + (void *)sram_suspend_address((unsigned long)pm_sram->emif_sram_table));
>> + if (ret) {
>> + pr_warn("PM: %s: EMIF function copy failed\n", __func__);
>> + return -EPROBE_DEFER;
>> + }
>
> Here's the dependency to the emif device I commented on earlier (and
> below).
>
I commented on this in the ti-emif-pm thread but we should be ok, we can't
remove that driver while pm33xx is loaded because of the direct call of exported
symbols, pm33xx holds a reference to ti-emif-pm until it is unloaded. I will
make sure the confirmation that these functions are valid is solid though.
>> +
>> + copy_addr = sram_exec_copy(sram_pool,
>> + (void *)sram_suspend_address((unsigned long)pm_sram->ro_sram_data),
>> + &ro_sram_data,
>> + sizeof(ro_sram_data));
>> + if (!copy_addr) {
>> + pr_err("PM: %s: ro_sram_data copy to sram failed\n", __func__);
>> + return -ENODEV;
>> + }
>> +
>> + return 0;
>> +}
>> +
>> +static int am33xx_pm_probe(struct platform_device *pdev)
>> +{
>> + struct device *dev = &pdev->dev;
>> + int ret;
>> +
>> + if (!of_machine_is_compatible("ti,am33xx") &&
>> + !of_machine_is_compatible("ti,am43"))
>> + return -ENODEV;
>> +
>> + pm_ops = dev->platform_data;
>> + if (!pm_ops) {
>> + pr_err("PM: Cannot get core PM ops!\n");
>> + return -ENODEV;
>> + }
>> +
>> + pm_sram = pm_ops->get_sram_addrs();
>> + if (!pm_sram) {
>> + pr_err("PM: Cannot get PM asm function addresses!!\n");
>> + return -ENODEV;
>> + }
>> +
>> + ret = am33xx_prepare_push_sram_idle();
>
> Perhaps calling this one am33xx_pm_alloc_sram() would be more
> descriptive (and match the release function)?
Not a bad point.
>
>> + if (ret)
>> + return ret;
>> +
>> + ret = am33xx_push_sram_idle();
>> + if (ret)
>> + goto err_free_sram;
>
> As I mentioned in my comments to the emif-sram driver, you may need to
> create device link to the emif-sram device to prevent it from going away
> under you here.
Addressed in ti-emif-pm thread.
>
>> +
>> + m3_ipc = wkup_m3_ipc_get();
>> + if (!m3_ipc) {
>> + pr_err("PM: Cannot get wkup_m3_ipc handle\n");
>
> You shouldn't log this as an error when probe is being deferred.
Yes, good point, just noise.
>
> Why not use dev_err and friends for logging now that you have a struct
> device?
I suppose I could now.
>
> And similarly to the emif-sram device, you may need to create a
> device-link also to the ipc device to prevent its driver from being
> unbound.
As described in the ti-emif-pm thread for that driver, we also call exported
symbols directly from wkup_m3_ipc driver, so pm33xx cannot probe at all if
wkup_m3_ipc is not loaded, and wkup_m3_ipc cannot be removed once pm33xx has
been loaded on top.
>
>> + ret = -EPROBE_DEFER;
>> + goto err_free_sram;
>> + }
>> +
>> + am33xx_pm_set_ipc_ops();
>> +
>> +#ifdef CONFIG_SUSPEND
>> + suspend_set_ops(&am33xx_pm_ops);
>> +#endif /* CONFIG_SUSPEND */
>
> This renders a lockdep splash about a circular locking dependency when
> suspending since we're taking the pm_mutex in suspend_set_ops here, and
> during suspend we flush any deferred probes while already holding the
> mutex:
>
> ======================================================
> WARNING: possible circular locking dependency detected
> 4.12.0-rc7 #11 Not tainted
> ------------------------------------------------------
> bash/404 is trying to acquire lock:
> (deferred_probe_work){+.+.+.}, at: [<c014cf3c>] flush_work+0x30/0x27c
>
> but task is already holding lock:
> (pm_mutex){+.+...}, at: [<c01792dc>] pm_suspend+0x190/0xc94
>
> which lock already depends on the new lock.
>
>
> the existing dependency chain (in reverse order) is:
>
> -> #1 (pm_mutex){+.+...}:
> __mutex_lock+0x80/0x694
> mutex_lock_nested+0x2c/0x34
> suspend_set_ops+0x4c/0x128
> am33xx_pm_probe+0x1fc/0x3a8
> platform_drv_probe+0x5c/0xc0
> driver_probe_device+0x37c/0x490
> __device_attach_driver+0xac/0x128
> bus_for_each_drv+0x74/0xa8
> __device_attach+0xc4/0x154
> device_initial_probe+0x1c/0x20
> bus_probe_device+0x98/0xa0
> deferred_probe_work_func+0x4c/0xe4
> process_one_work+0x1f4/0x758
> worker_thread+0x1e0/0x514
> kthread+0x128/0x158
> ret_from_fork+0x14/0x24
>
> -> #0 (deferred_probe_work){+.+.+.}:
> lock_acquire+0x108/0x264
> flush_work+0x60/0x27c
> wait_for_device_probe+0x24/0xa4
> dpm_prepare+0xd0/0x91c
> dpm_suspend_start+0x1c/0x70
> suspend_devices_and_enter+0xc4/0xeac
> pm_suspend+0x890/0xc94
> state_store+0x80/0xdc
> kobj_attr_store+0x1c/0x28
> sysfs_kf_write+0x5c/0x60
> kernfs_fop_write+0x128/0x254
> __vfs_write+0x38/0x128
> vfs_write+0xb4/0x174
> SyS_write+0x54/0xb0
> ret_fast_syscall+0x0/0x1c
>
Yes thanks, I have seen this before myself now. I will need to look closer into
eliminating this. I am not sure how it is happening, pm_suspend should not be
able to be called if suspend_set_ops has not completed, at which point it should
have released the mutex.
Regards,
Dave
> Johan
>
^ permalink raw reply [flat|nested] 15+ messages in thread* Re: [PATCH v2 4/5] soc: ti: Add pm33xx driver for basic suspend support
2017-07-06 19:08 ` Dave Gerlach
@ 2017-07-10 11:46 ` Johan Hovold
0 siblings, 0 replies; 15+ messages in thread
From: Johan Hovold @ 2017-07-10 11:46 UTC (permalink / raw)
To: Dave Gerlach
Cc: Johan Hovold, Tony Lindgren, Santosh Shilimkar, Russell King,
linux-arm-kernel, linux-omap, linux-kernel, Keerthy J
On Thu, Jul 06, 2017 at 02:08:07PM -0500, Dave Gerlach wrote:
> On 07/03/2017 11:54 AM, Johan Hovold wrote:
> > On Fri, May 19, 2017 at 03:04:37PM -0500, Dave Gerlach wrote:
> >> AM335x and AM437x support various low power modes as documented
> >> in section 8.1.4.3 of the AM335x Technical Reference Manual and
> >> section 6.4.3 of the AM437x Technical Reference Manual.
> >>
> >> DeepSleep0 mode offers the lowest power mode with limited
> >> wakeup sources without a system reboot and is mapped as
> >> the suspend state in the kernel. In this state, MPU and
> >> PER domains are turned off with the internal RAM held in
> >> retention to facilitate the resume process. As part of
> >> the boot process, the assembly code is copied over to OCMCRAM
> >> so it can be executed to turn of the EMIF and put DDR into self
> >> refresh.
> >>
> >> Both platforms have a Cortex-M3 (WKUP_M3) which assists the MPU
> >> in DeepSleep0 entry and exit. WKUP_M3 takes care
> >> of the clockdomain and powerdomain transitions based on the
> >> intended low power state. MPU needs to load the appropriate
> >> WKUP_M3 binary onto the WKUP_M3 memory space before it can
> >> leverage any of the PM features like DeepSleep. This loading
> >> is handled by the remoteproc driver wkup_m3_rproc.
> >>
> >> Communication with the WKUP_M3 is handled by a wkup_m3_ipc
> >> driver that exposes the specific PM functionality to be used
> >> the PM code.
> > And similarly to the emif-sram device, you may need to create a
> > device-link also to the ipc device to prevent its driver from being
> > unbound.
>
> As described in the ti-emif-pm thread for that driver, we also call exported
> symbols directly from wkup_m3_ipc driver, so pm33xx cannot probe at all if
> wkup_m3_ipc is not loaded, and wkup_m3_ipc cannot be removed once pm33xx has
> been loaded on top.
As discussed in the other thread, the ipc driver can be unbound from its
device even if the module remains loaded.
> >
> >> + ret = -EPROBE_DEFER;
> >> + goto err_free_sram;
> >> + }
> >> +
> >> + am33xx_pm_set_ipc_ops();
> >> +
> >> +#ifdef CONFIG_SUSPEND
> >> + suspend_set_ops(&am33xx_pm_ops);
> >> +#endif /* CONFIG_SUSPEND */
> >
> > This renders a lockdep splash about a circular locking dependency when
> > suspending since we're taking the pm_mutex in suspend_set_ops here, and
> > during suspend we flush any deferred probes while already holding the
> > mutex:
> >
> > ======================================================
> > WARNING: possible circular locking dependency detected
> > 4.12.0-rc7 #11 Not tainted
> > ------------------------------------------------------
> > bash/404 is trying to acquire lock:
> > (deferred_probe_work){+.+.+.}, at: [<c014cf3c>] flush_work+0x30/0x27c
> >
> > but task is already holding lock:
> > (pm_mutex){+.+...}, at: [<c01792dc>] pm_suspend+0x190/0xc94
> >
> > which lock already depends on the new lock.
> >
> >
> > the existing dependency chain (in reverse order) is:
> >
> > -> #1 (pm_mutex){+.+...}:
> > __mutex_lock+0x80/0x694
> > mutex_lock_nested+0x2c/0x34
> > suspend_set_ops+0x4c/0x128
> > am33xx_pm_probe+0x1fc/0x3a8
> > platform_drv_probe+0x5c/0xc0
> > driver_probe_device+0x37c/0x490
> > __device_attach_driver+0xac/0x128
> > bus_for_each_drv+0x74/0xa8
> > __device_attach+0xc4/0x154
> > device_initial_probe+0x1c/0x20
> > bus_probe_device+0x98/0xa0
> > deferred_probe_work_func+0x4c/0xe4
> > process_one_work+0x1f4/0x758
> > worker_thread+0x1e0/0x514
> > kthread+0x128/0x158
> > ret_from_fork+0x14/0x24
> >
> > -> #0 (deferred_probe_work){+.+.+.}:
> > lock_acquire+0x108/0x264
> > flush_work+0x60/0x27c
> > wait_for_device_probe+0x24/0xa4
> > dpm_prepare+0xd0/0x91c
> > dpm_suspend_start+0x1c/0x70
> > suspend_devices_and_enter+0xc4/0xeac
> > pm_suspend+0x890/0xc94
> > state_store+0x80/0xdc
> > kobj_attr_store+0x1c/0x28
> > sysfs_kf_write+0x5c/0x60
> > kernfs_fop_write+0x128/0x254
> > __vfs_write+0x38/0x128
> > vfs_write+0xb4/0x174
> > SyS_write+0x54/0xb0
> > ret_fast_syscall+0x0/0x1c
> >
>
> Yes thanks, I have seen this before myself now. I will need to look closer into
> eliminating this. I am not sure how it is happening, pm_suspend should not be
> able to be called if suspend_set_ops has not completed, at which point it should
> have released the mutex.
So perhaps the deadlock cannot happen in practise then even if both
paths can indeed be taken (which triggers the lockdep warning).
Johan
^ permalink raw reply [flat|nested] 15+ messages in thread
* [PATCH v2 5/5] ARM: OMAP2+: Create dummy platform_device for pm33xx
2017-05-19 20:04 [PATCH v2 0/5] ARM: OMAP2+: AM33XX/AM43XX: Add suspend-resume support Dave Gerlach
` (3 preceding siblings ...)
2017-05-19 20:04 ` [PATCH v2 4/5] soc: ti: Add pm33xx driver for basic suspend support Dave Gerlach
@ 2017-05-19 20:04 ` Dave Gerlach
2017-07-03 16:58 ` Johan Hovold
4 siblings, 1 reply; 15+ messages in thread
From: Dave Gerlach @ 2017-05-19 20:04 UTC (permalink / raw)
To: Tony Lindgren, Santosh Shilimkar, Russell King
Cc: linux-arm-kernel, linux-omap, linux-kernel, Dave Gerlach, Keerthy J
Add amx3_common_pm_init to create a dummy platform_device for
pm33xx so that our pm33xx module can probe and am335x and am437x
platforms to enable basic suspend to mem and standby support.
Signed-off-by: Dave Gerlach <d-gerlach@ti.com>
---
arch/arm/mach-omap2/common.h | 7 +++++++
arch/arm/mach-omap2/io.c | 2 ++
arch/arm/mach-omap2/pm33xx-core.c | 12 ++++++++++++
3 files changed, 21 insertions(+)
diff --git a/arch/arm/mach-omap2/common.h b/arch/arm/mach-omap2/common.h
index 3089d3bfa19b..cd7724d040f8 100644
--- a/arch/arm/mach-omap2/common.h
+++ b/arch/arm/mach-omap2/common.h
@@ -77,6 +77,13 @@ static inline int omap4_pm_init_early(void)
}
#endif
+#if defined(CONFIG_PM) && (defined(CONFIG_SOC_AM33XX) || \
+ defined(CONFIG_SOC_AM43XX))
+void amx3_common_pm_init(void);
+#else
+static inline void amx3_common_pm_init(void) { }
+#endif
+
extern void omap2_init_common_infrastructure(void);
extern void omap_init_time(void);
diff --git a/arch/arm/mach-omap2/io.c b/arch/arm/mach-omap2/io.c
index 5aafb8449c40..1bbbf19c93ea 100644
--- a/arch/arm/mach-omap2/io.c
+++ b/arch/arm/mach-omap2/io.c
@@ -652,6 +652,7 @@ void __init am33xx_init_early(void)
void __init am33xx_init_late(void)
{
omap_common_late_init();
+ amx3_common_pm_init();
}
#endif
@@ -676,6 +677,7 @@ void __init am43xx_init_late(void)
{
omap_common_late_init();
omap2_clk_enable_autoidle_all();
+ amx3_common_pm_init();
}
#endif
diff --git a/arch/arm/mach-omap2/pm33xx-core.c b/arch/arm/mach-omap2/pm33xx-core.c
index c84ffc4de2e9..b5d90841c27a 100644
--- a/arch/arm/mach-omap2/pm33xx-core.c
+++ b/arch/arm/mach-omap2/pm33xx-core.c
@@ -179,3 +179,15 @@ struct am33xx_pm_platform_data *am33xx_pm_get_pdata(void)
else
return NULL;
}
+
+void __init amx3_common_pm_init(void)
+{
+ struct platform_device_info devinfo = { };
+ struct am33xx_pm_platform_data *pdata;
+
+ pdata = am33xx_pm_get_pdata();
+ devinfo.name = "pm33xx";
+ devinfo.data = pdata;
+ devinfo.size_data = sizeof(*pdata);
+ platform_device_register_full(&devinfo);
+}
--
2.13.0
^ permalink raw reply related [flat|nested] 15+ messages in thread* Re: [PATCH v2 5/5] ARM: OMAP2+: Create dummy platform_device for pm33xx
2017-05-19 20:04 ` [PATCH v2 5/5] ARM: OMAP2+: Create dummy platform_device for pm33xx Dave Gerlach
@ 2017-07-03 16:58 ` Johan Hovold
2017-07-06 19:08 ` Dave Gerlach
0 siblings, 1 reply; 15+ messages in thread
From: Johan Hovold @ 2017-07-03 16:58 UTC (permalink / raw)
To: Dave Gerlach
Cc: Tony Lindgren, Santosh Shilimkar, Russell King, Keerthy J,
linux-omap, linux-kernel, linux-arm-kernel
On Fri, May 19, 2017 at 03:04:38PM -0500, Dave Gerlach wrote:
> Add amx3_common_pm_init to create a dummy platform_device for
> pm33xx so that our pm33xx module can probe and am335x and am437x
> platforms to enable basic suspend to mem and standby support.
>
> Signed-off-by: Dave Gerlach <d-gerlach@ti.com>
> ---
> +void __init amx3_common_pm_init(void)
> +{
> + struct platform_device_info devinfo = { };
You should make sure devinfo is zeroed, and also set .id to -1.
> + struct am33xx_pm_platform_data *pdata;
> +
> + pdata = am33xx_pm_get_pdata();
> + devinfo.name = "pm33xx";
> + devinfo.data = pdata;
> + devinfo.size_data = sizeof(*pdata);
> + platform_device_register_full(&devinfo);
> +}
Johan
^ permalink raw reply [flat|nested] 15+ messages in thread* Re: [PATCH v2 5/5] ARM: OMAP2+: Create dummy platform_device for pm33xx
2017-07-03 16:58 ` Johan Hovold
@ 2017-07-06 19:08 ` Dave Gerlach
0 siblings, 0 replies; 15+ messages in thread
From: Dave Gerlach @ 2017-07-06 19:08 UTC (permalink / raw)
To: Johan Hovold
Cc: Tony Lindgren, Santosh Shilimkar, Russell King, Keerthy J,
linux-omap, linux-kernel, linux-arm-kernel
On 07/03/2017 11:58 AM, Johan Hovold wrote:
> On Fri, May 19, 2017 at 03:04:38PM -0500, Dave Gerlach wrote:
>> Add amx3_common_pm_init to create a dummy platform_device for
>> pm33xx so that our pm33xx module can probe and am335x and am437x
>> platforms to enable basic suspend to mem and standby support.
>>
>> Signed-off-by: Dave Gerlach <d-gerlach@ti.com>
>> ---
>
>> +void __init amx3_common_pm_init(void)
>> +{
>> + struct platform_device_info devinfo = { };
>
> You should make sure devinfo is zeroed, and also set .id to -1.
Thanks for the comment, will look into updating this for next version.
Regards,
Dave
>
>> + struct am33xx_pm_platform_data *pdata;
>> +
>> + pdata = am33xx_pm_get_pdata();
>> + devinfo.name = "pm33xx";
>> + devinfo.data = pdata;
>> + devinfo.size_data = sizeof(*pdata);
>> + platform_device_register_full(&devinfo);
>> +}
>
> Johan
>
^ permalink raw reply [flat|nested] 15+ messages in thread