ENGR00155219 [MX6]Add protection for dormant mode

1. clean up ddr io code, using macro define;
2. we should consider if the wake up irq comes
during execution of low-power(ms6q_suspend.S)
code but before ARM enter wfi, in this scenario,
system will not enter STOP mode, thus, the resume
code will cause system fail, so we need to consider
if system can not enter STOP mode, should resume
immediately after wfi.

Signed-off-by: Anson Huang <b20788@freescale.com>

2 files changed, 181 insertions, 167 deletions

diff --git a/arch/arm/mach-mx6/mx6q_suspend.S b/arch/arm/mach-mx6/mx6q_suspend.S
index 5d2aca1c9dd..4279a527b64 100644
--- a/arch/arm/mach-mx6/mx6q_suspend.S
+++ b/arch/arm/mach-mx6/mx6q_suspend.S
@@ -49,6 +49,162 @@ see define in include/linux/suspend.h
 r1: iram_paddr
 r2: suspend_iram_base
 *************************************************************/
+	.macro	ddr_io_save
+
+	ldr	r4, [r1, #0x5ac] /* DRAM_DQM0 */
+	ldr	r5, [r1, #0x5b4] /* DRAM_DQM1 */
+	ldr	r6, [r1, #0x528] /* DRAM_DQM2 */
+	ldr	r7, [r1, #0x520] /* DRAM_DQM3 */
+	stmfd	r0!, {r4-r7}
+
+	ldr	r4, [r1, #0x514] /* DRAM_DQM4 */
+	ldr	r5, [r1, #0x510] /* DRAM_DQM5 */
+	ldr	r6, [r1, #0x5bc] /* DRAM_DQM6 */
+	ldr	r7, [r1, #0x5c4] /* DRAM_DQM7 */
+	stmfd	r0!, {r4-r7}
+
+	ldr	r4, [r1, #0x56c] /* DRAM_CAS */
+	ldr	r5, [r1, #0x578] /* DRAM_RAS */
+	ldr	r6, [r1, #0x588] /* DRAM_SDCLK_0 */
+	ldr	r7, [r1, #0x594] /* DRAM_SDCLK_1 */
+	stmfd	r0!, {r4-r7}
+
+	ldr	r5, [r1, #0x750] /* DDRMODE_CTL */
+	ldr	r6, [r1, #0x774] /* DDRMODE */
+	stmfd	r0!, {r5-r6}
+
+	ldr	r4, [r1, #0x5a8] /* DRAM_SDQS0 */
+	ldr	r5, [r1, #0x5b0] /* DRAM_SDQS1 */
+	ldr	r6, [r1, #0x524] /* DRAM_SDQS2 */
+	ldr	r7, [r1, #0x51c] /* DRAM_SDQS3 */
+	stmfd	r0!, {r4-r7}
+
+	ldr	r4, [r1, #0x518] /* DRAM_SDQS4 */
+	ldr	r5, [r1, #0x50c] /* DRAM_SDQS5 */
+	ldr	r6, [r1, #0x5b8] /* DRAM_SDQS6 */
+	ldr	r7, [r1, #0x5c0] /* DRAM_SDQS7 */
+	stmfd	r0!, {r4-r7}
+
+	ldr	r4, [r1, #0x784] /* GPR_B0DS */
+	ldr	r5, [r1, #0x788] /* GPR_B1DS */
+	ldr	r6, [r1, #0x794] /* GPR_B2DS */
+	ldr	r7, [r1, #0x79c] /* GPR_B3DS */
+	stmfd	r0!, {r4-r7}
+
+	ldr	r4, [r1, #0x7a0] /* GPR_B4DS */
+	ldr	r5, [r1, #0x7a4] /* GPR_B5DS */
+	ldr	r6, [r1, #0x7a8] /* GPR_B6DS */
+	ldr	r7, [r1, #0x748] /* GPR_B7DS */
+	stmfd	r0!, {r4-r7}
+
+	ldr	r5, [r1, #0x74c] /* GPR_ADDS*/
+	ldr	r6, [r1, #0x59c] /* DRAM_SODT0*/
+	ldr	r7, [r1, #0x5a0] /* DRAM_SODT1*/
+	stmfd	r0!, {r5-r7}
+
+	.endm
+
+	.macro	ddr_io_restore
+
+	ldmea	r0!, {r4-r7}
+	str	r4, [r1, #0x5ac] /* DRAM_DQM0 */
+	str	r5, [r1, #0x5b4] /* DRAM_DQM1 */
+	str	r6, [r1, #0x528] /* DRAM_DQM2 */
+	str	r7, [r1, #0x520] /* DRAM_DQM3 */
+
+	ldmea	r0!, {r4-r7}
+	str	r4, [r1, #0x514] /* DRAM_DQM4 */
+	str	r5, [r1, #0x510] /* DRAM_DQM5 */
+	str	r6, [r1, #0x5bc] /* DRAM_DQM6 */
+	str	r7, [r1, #0x5c4] /* DRAM_DQM7 */
+
+	ldmea	r0!, {r4-r7}
+	str	r4, [r1, #0x56c] /* DRAM_CAS */
+	str	r5, [r1, #0x578] /* DRAM_RAS */
+	str	r6, [r1, #0x588] /* DRAM_SDCLK_0 */
+	str	r7, [r1, #0x594] /* DRAM_SDCLK_1 */
+
+	ldmea	r0!, {r5-r6}
+	str	r5, [r1, #0x750] /* DDRMODE_CTL */
+	str	r6, [r1, #0x774] /* DDRMODE */
+
+	ldmea	r0!, {r4-r7}
+	str	r4, [r1, #0x5a8] /* DRAM_SDQS0 */
+	str	r5, [r1, #0x5b0] /* DRAM_SDQS1 */
+	str	r6, [r1, #0x524] /* DRAM_SDQS2 */
+	str	r7, [r1, #0x51c] /* DRAM_SDQS3 */
+
+	ldmea	r0!, {r4-r7}
+	str	r4, [r1, #0x518] /* DRAM_SDQS4 */
+	str	r5, [r1, #0x50c] /* DRAM_SDQS5 */
+	str	r6, [r1, #0x5b8] /* DRAM_SDQS6 */
+	str	r7, [r1, #0x5c0] /* DRAM_SDQS7 */
+
+	ldmea	r0!, {r4-r7}
+	str	r4, [r1, #0x784] /* GPR_B0DS */
+	str	r5, [r1, #0x788] /* GPR_B1DS */
+	str	r6, [r1, #0x794] /* GPR_B2DS */
+	str	r7, [r1, #0x79c] /* GPR_B3DS */
+
+	ldmea	r0!, {r4-r7}
+	str	r4, [r1, #0x7a0] /* GPR_B4DS */
+	str	r5, [r1, #0x7a4] /* GPR_B5DS */
+	str	r6, [r1, #0x7a8] /* GPR_B6DS */
+	str	r7, [r1, #0x748] /* GPR_B7DS */
+
+	ldmea	r0!, {r5-r7}
+	str	r5, [r1, #0x74c] /* GPR_ADDS*/
+	str	r6, [r1, #0x59c] /* DRAM_SODT0*/
+	str	r7, [r1, #0x5a0] /* DRAM_SODT1*/
+
+	.endm
+
+	.macro	ddr_io_set_lpm
+
+	mov	r0, #0
+	str	r0, [r1, #0x5ac] /* DRAM_DQM0 */
+	str	r0, [r1, #0x5b4] /* DRAM_DQM1 */
+	str	r0, [r1, #0x528] /* DRAM_DQM2 */
+	str	r0, [r1, #0x520] /* DRAM_DQM3 */
+
+	str	r0, [r1, #0x514] /* DRAM_DQM4 */
+	str	r0, [r1, #0x510] /* DRAM_DQM5 */
+	str	r0, [r1, #0x5bc] /* DRAM_DQM6 */
+	str	r0, [r1, #0x5c4] /* DRAM_DQM7 */
+
+	str	r0, [r1, #0x56c] /* DRAM_CAS */
+	str	r0, [r1, #0x578] /* DRAM_RAS */
+	str	r0, [r1, #0x588] /* DRAM_SDCLK_0 */
+	str	r0, [r1, #0x594] /* DRAM_SDCLK_1 */
+
+	str	r0, [r1, #0x750] /* DDRMODE_CTL */
+	str	r0, [r1, #0x774] /* DDRMODE */
+
+	str	r0, [r1, #0x5a8] /* DRAM_SDQS0 */
+	str	r0, [r1, #0x5b0] /* DRAM_SDQS1 */
+	str	r0, [r1, #0x524] /* DRAM_SDQS2 */
+	str	r0, [r1, #0x51c] /* DRAM_SDQS3 */
+
+	str	r0, [r1, #0x518] /* DRAM_SDQS4 */
+	str	r0, [r1, #0x50c] /* DRAM_SDQS5 */
+	str	r0, [r1, #0x5b8] /* DRAM_SDQS6 */
+	str	r0, [r1, #0x5c0] /* DRAM_SDQS7 */
+
+	str	r0, [r1, #0x784] /* GPR_B0DS */
+	str	r0, [r1, #0x788] /* GPR_B1DS */
+	str	r0, [r1, #0x794] /* GPR_B2DS */
+	str	r0, [r1, #0x79c] /* GPR_B3DS */
+
+	str	r0, [r1, #0x7a0] /* GPR_B4DS */
+	str	r0, [r1, #0x7a4] /* GPR_B5DS */
+	str	r0, [r1, #0x7a8] /* GPR_B6DS */
+	str	r0, [r1, #0x748] /* GPR_B7DS */
+
+	str	r0, [r1, #0x74c] /* GPR_ADDS*/
+	str	r0, [r1, #0x59c] /* DRAM_SODT0*/
+	str	r0, [r1, #0x5a0] /* DRAM_SODT1*/
+
+	.endm
 
 ENTRY(mx6q_suspend)
 	stmfd	sp!, {r0-r12}     @ Save registers
@@ -111,61 +267,11 @@ ddr_iomux_save:
 	ldr	r1, =MX6Q_IOMUXC_BASE_ADDR
 	add	r1, r1, #PERIPBASE_VIRT
 
-	ldr	r4, [r1, #0x5ac] /* DRAM_DQM0 */
-	ldr	r5, [r1, #0x5b4] /* DRAM_DQM1 */
-	ldr	r6, [r1, #0x528] /* DRAM_DQM2 */
-	ldr	r7, [r1, #0x520] /* DRAM_DQM3 */
-	stmfd	r0!, {r4-r7}
-
-	ldr	r4, [r1, #0x514] /* DRAM_DQM4 */
-	ldr	r5, [r1, #0x510] /* DRAM_DQM5 */
-	ldr	r6, [r1, #0x5bc] /* DRAM_DQM6 */
-	ldr	r7, [r1, #0x5c4] /* DRAM_DQM7 */
-	stmfd	r0!, {r4-r7}
-
-	ldr	r4, [r1, #0x56c] /* DRAM_CAS */
-	ldr	r5, [r1, #0x578] /* DRAM_RAS */
-	ldr	r6, [r1, #0x588] /* DRAM_SDCLK_0 */
-	ldr	r7, [r1, #0x594] /* DRAM_SDCLK_1 */
-	stmfd	r0!, {r4-r7}
-
-	ldr	r5, [r1, #0x750] /* DDRMODE_CTL */
-	ldr	r6, [r1, #0x774] /* DDRMODE */
-	stmfd	r0!, {r5-r6}
-
-	ldr	r4, [r1, #0x5a8] /* DRAM_SDQS0 */
-	ldr	r5, [r1, #0x5b0] /* DRAM_SDQS1 */
-	ldr	r6, [r1, #0x524] /* DRAM_SDQS2 */
-	ldr	r7, [r1, #0x51c] /* DRAM_SDQS3 */
-	stmfd	r0!, {r4-r7}
+	ddr_io_save
 
-	ldr	r4, [r1, #0x518] /* DRAM_SDQS4 */
-	ldr	r5, [r1, #0x50c] /* DRAM_SDQS5 */
-	ldr	r6, [r1, #0x5b8] /* DRAM_SDQS6 */
-	ldr	r7, [r1, #0x5c0] /* DRAM_SDQS7 */
-	stmfd	r0!, {r4-r7}
-
-	ldr	r4, [r1, #0x784] /* GPR_B0DS */
-	ldr	r5, [r1, #0x788] /* GPR_B1DS */
-	ldr	r6, [r1, #0x794] /* GPR_B2DS */
-	ldr	r7, [r1, #0x79c] /* GPR_B3DS */
-	stmfd	r0!, {r4-r7}
-
-	ldr	r4, [r1, #0x7a0] /* GPR_B4DS */
-	ldr	r5, [r1, #0x7a4] /* GPR_B5DS */
-	ldr	r6, [r1, #0x7a8] /* GPR_B6DS */
-	ldr	r7, [r1, #0x748] /* GPR_B7DS */
-	stmfd	r0!, {r4-r7}
-
-	ldr	r5, [r1, #0x74c] /* GPR_ADDS*/
-	ldr	r6, [r1, #0x59c] /* DRAM_SODT0*/
-	ldr	r7, [r1, #0x5a0] /* DRAM_SODT1*/
-	stmfd	r0!, {r5-r7}
-ddr_iomux_save_done:
-
-	mov	r4, sp		@ Store sp
-	mrs	r5, spsr	@ Store spsr
-	mov	r6, lr		@ Store lr
+	mov	r4, sp			@ Store sp
+	mrs	r5, spsr		@ Store spsr
+	mov	r6, lr			@ Store lr
 	stmfd	r0!, {r4-r6}
 
 	/* c1 and c2 registers */
@@ -197,11 +303,11 @@ ddr_iomux_save_done:
 	 * Flush all data from the L1 data cache before disabling
 	 * SCTLR.C bit.
 	 */
-	push	{r0-r12}
+	push	{r0-r12, lr}
 	ldr	r0, =v7_flush_dcache_all
 	mov	lr, pc
 	mov	pc, r0
-	pop	{r0-r12}
+	pop	{r0-r12, lr}
 
 	/*
 	 * Clear the SCTLR.C bit to prevent further data cache
@@ -218,11 +324,11 @@ ddr_iomux_save_done:
 	 * necessary exported flush API is used here. Doing clean
 	 * on already clean cache would be almost NOP.
 	 */
-	push	{r0-r12}
+	push	{r0-r12, lr}
 	ldr	r0, =v7_flush_dcache_all
 	mov	lr, pc
 	mov	pc, r0
-	pop	{r0-r12}
+	pop	{r0-r12, lr}
 
 	/*
 	 * Execute an ISB instruction to ensure that all of the
@@ -241,64 +347,22 @@ ddr_iomux_save_done:
 /****************************************************************
 set ddr iomux to low power mode
 ****************************************************************/
-ddr_iomux_set_lpm:
 	ldr	r1, =MMDC_P0_BASE_ADDR
 	add	r1, r1, #PERIPBASE_VIRT
 	ldr	r0, [r1, #MMDC_MAPSR_OFFSET]
-	bic	r0, #MMDC_MAPSR_PSD /* enable power saving */
+	bic	r0, #MMDC_MAPSR_PSD 		/* enable lpm */
 	str	r0, [r1, #MMDC_MAPSR_OFFSET]
 refresh:
-	ldr	r0, [r1, #MMDC_MAPSR_OFFSET] /* MMDC_MAPSR */
-	and	r0, r0, #MMDC_MAPSR_PSS /* PSS bit */
+	ldr	r0, [r1, #MMDC_MAPSR_OFFSET] 	/* MMDC_MAPSR */
+	and	r0, r0, #MMDC_MAPSR_PSS 	/* PSS bit */
 	cmp	r0, #0
 	beq	refresh
 
 	/* set mmdc iomux to low power mode */
 	ldr	r1, =MX6Q_IOMUXC_BASE_ADDR
 	add	r1, r1, #PERIPBASE_VIRT
-	mov	r0 , #0
-	str	r0, [r1, #0x5ac] /* DRAM_DQM0 */
-	str	r0, [r1, #0x5b4] /* DRAM_DQM1 */
-	str	r0, [r1, #0x528] /* DRAM_DQM2 */
-	str	r0, [r1, #0x520] /* DRAM_DQM3 */
 
-	str	r0, [r1, #0x514] /* DRAM_DQM4 */
-	str	r0, [r1, #0x510] /* DRAM_DQM5 */
-	str	r0, [r1, #0x5bc] /* DRAM_DQM6 */
-	str	r0, [r1, #0x5c4] /* DRAM_DQM7 */
-
-	str	r0, [r1, #0x56c] /* DRAM_CAS */
-	str	r0, [r1, #0x578] /* DRAM_RAS */
-	str	r0, [r1, #0x588] /* DRAM_SDCLK_0 */
-	str	r0, [r1, #0x594] /* DRAM_SDCLK_1 */
-
-	str	r0, [r1, #0x750] /* DDRMODE_CTL */
-	str	r0, [r1, #0x774] /* DDRMODE */
-
-	str	r0, [r1, #0x5a8] /* DRAM_SDQS0 */
-	str	r0, [r1, #0x5b0] /* DRAM_SDQS1 */
-	str	r0, [r1, #0x524] /* DRAM_SDQS2 */
-	str	r0, [r1, #0x51c] /* DRAM_SDQS3 */
-
-	str	r0, [r1, #0x518] /* DRAM_SDQS4 */
-	str	r0, [r1, #0x50c] /* DRAM_SDQS5 */
-	str	r0, [r1, #0x5b8] /* DRAM_SDQS6 */
-	str	r0, [r1, #0x5c0] /* DRAM_SDQS7 */
-
-	str	r0, [r1, #0x784] /* GPR_B0DS */
-	str	r0, [r1, #0x788] /* GPR_B1DS */
-	str	r0, [r1, #0x794] /* GPR_B2DS */
-	str	r0, [r1, #0x79c] /* GPR_B3DS */
-
-	str	r0, [r1, #0x7a0] /* GPR_B4DS */
-	str	r0, [r1, #0x7a4] /* GPR_B5DS */
-	str	r0, [r1, #0x7a8] /* GPR_B6DS */
-	str	r0, [r1, #0x748] /* GPR_B7DS */
-
-	str	r0, [r1, #0x74c] /* GPR_ADDS*/
-	str	r0, [r1, #0x59c] /* DRAM_SODT0*/
-	str	r0, [r1, #0x5a0] /* DRAM_SODT1*/
-ddr_iomux_set_lpm_done:
+	ddr_io_set_lpm
 /****************************************************************
 save resume pointer into SRC_GPR1
 ****************************************************************/
@@ -320,14 +384,22 @@ execute a wfi instruction to let SOC go into stop mode.
 	nop
 
 /****************************************************************
-never go here.
+if go here, means there is a wakeup irq pending, we should resume
+system immediately.
 ****************************************************************/
+	mov	r0, r2 		/* get suspend_iram_base */
+	add	r0, r0, #IRAM_SUSPEND_SIZE	/* 4K */
 
+	ldr	r1, =MX6Q_IOMUXC_BASE_ADDR
+	add	r1, r1, #PERIPBASE_VIRT
 
+	ddr_io_restore
 
+	mrc	p15, 0, r1, c1, c0, 0
+	orr	r1, r1, #(1 << 2)	@ Enable the C bit
+	mcr	p15, 0, r1, c1, c0, 0
 
-
-
+	b 	out	/* exit standby */
 
 /****************************************************************
 when SOC exit stop mode, arm core restart from here, currently
@@ -338,66 +410,10 @@ resume:
 	ldr	r0, =SRC_BASE_ADDR
 	str	r1, [r0, #SRC_GPR1_OFFSET] /* clear SRC_GPR1 */
 	ldr	r0, [r0, #SRC_GPR2_OFFSET]
-ddr_iomux_restore:
-	ldr	r1, =MX6Q_IOMUXC_BASE_ADDR
-	ldmea	r0!, {r4-r7}
-	str	r4, [r1, #0x5ac] /* DRAM_DQM0 */
-	str	r5, [r1, #0x5b4] /* DRAM_DQM1 */
-	str	r6, [r1, #0x528] /* DRAM_DQM2 */
-	str	r7, [r1, #0x520] /* DRAM_DQM3 */
-
-	ldmea	r0!, {r4-r7}
-	str	r4, [r1, #0x514] /* DRAM_DQM4 */
-	str	r5, [r1, #0x510] /* DRAM_DQM5 */
-	str	r6, [r1, #0x5bc] /* DRAM_DQM6 */
-	str	r7, [r1, #0x5c4] /* DRAM_DQM7 */
-
-	ldmea	r0!, {r4-r7}
-	str	r4, [r1, #0x56c] /* DRAM_CAS */
-	str	r5, [r1, #0x578] /* DRAM_RAS */
-	str	r6, [r1, #0x588] /* DRAM_SDCLK_0 */
-	str	r7, [r1, #0x594] /* DRAM_SDCLK_1 */
-
-	ldmea	r0!, {r5-r6}
-	@str 	r4, [r1, #0x57c] /* DRAM_RESET */
-	str	r5, [r1, #0x750] /* DDRMODE_CTL */
-	str	r6, [r1, #0x774] /* DDRMODE */
 
-	ldmea	r0!, {r4-r7}
-	str	r4, [r1, #0x5a8] /* DRAM_SDQS0 */
-	str	r5, [r1, #0x5b0] /* DRAM_SDQS1 */
-	str	r6, [r1, #0x524] /* DRAM_SDQS2 */
-	str	r7, [r1, #0x51c] /* DRAM_SDQS3 */
-
-	ldmea	r0!, {r4-r7}
-	str	r4, [r1, #0x518] /* DRAM_SDQS4 */
-	str	r5, [r1, #0x50c] /* DRAM_SDQS5 */
-	str	r6, [r1, #0x5b8] /* DRAM_SDQS6 */
-	str	r7, [r1, #0x5c0] /* DRAM_SDQS7 */
-
-	ldmea	r0!, {r4-r7}
-	str	r4, [r1, #0x784] /* GPR_B0DS */
-	str	r5, [r1, #0x788] /* GPR_B1DS */
-	str	r6, [r1, #0x794] /* GPR_B2DS */
-	str	r7, [r1, #0x79c] /* GPR_B3DS */
-
-	ldmea	r0!, {r4-r7}
-	str	r4, [r1, #0x7a0] /* GPR_B4DS */
-	str	r5, [r1, #0x7a4] /* GPR_B5DS */
-	str	r6, [r1, #0x7a8] /* GPR_B6DS */
-	str	r7, [r1, #0x748] /* GPR_B7DS */
-
-	ldmea	r0!, {r5-r7}
-	str	r5, [r1, #0x74c] /* GPR_ADDS*/
-	str	r6, [r1, #0x59c] /* DRAM_SODT0*/
-	str	r7, [r1, #0x5a0] /* DRAM_SODT1*/
-ddr_iomux_restore_done:
+	ldr	r1, =MX6Q_IOMUXC_BASE_ADDR
+	ddr_io_restore
 
-	ldr	r2, =ddr
-	ldr	r1, =va2pa_offset
-	sub	r2, r2, r1
-	mov	pc, r2
-ddr:
 	/* Restore cp15 registers */
 	ldmea	r0!, {r4-r6}
 	mov	sp, r4
diff --git a/arch/arm/mach-mx6/pm.c b/arch/arm/mach-mx6/pm.c
index 622ec5a241f..45e43977a53 100644
--- a/arch/arm/mach-mx6/pm.c
+++ b/arch/arm/mach-mx6/pm.c
@@ -77,7 +77,6 @@ static void __iomem *src_base;
 static void __iomem *local_twd_base;
 static void __iomem *gic_dist_base;
 static void __iomem *gic_cpu_base;
-static void __iomem *uart4_base;
 
 static void *suspend_iram_base;
 static void (*suspend_in_iram)(suspend_state_t state,
@@ -284,7 +283,6 @@ static int __init pm_init(void)
 	gic_dist_base = IO_ADDRESS(IC_DISTRIBUTOR_BASE_ADDR);
 	gic_cpu_base = IO_ADDRESS(IC_INTERFACES_BASE_ADDR);
 	local_twd_base = IO_ADDRESS(LOCAL_TWD_ADDR);
-	uart4_base = IO_ADDRESS(0x21f0000);
 
 	pr_info("Static Power Management for Freescale i.MX6\n");