[PATCH 1/6] pm: at91: pm_slowclock: create the procedure to handle the sdram self-refresh

From: Wenyou Yang
Date: Wed Feb 11 2015 - 21:47:56 EST


To decrease the duplicated code, create the special procedure
to contain both activing and exiting the sdram self-refresh mode.

Signed-off-by: Wenyou Yang <wenyou.yang@xxxxxxxxx>
---
arch/arm/mach-at91/pm_slowclock.S | 239 +++++++++++++++++++++----------------
1 file changed, 137 insertions(+), 102 deletions(-)

diff --git a/arch/arm/mach-at91/pm_slowclock.S b/arch/arm/mach-at91/pm_slowclock.S
index 4e55665..6fdf221 100644
--- a/arch/arm/mach-at91/pm_slowclock.S
+++ b/arch/arm/mach-at91/pm_slowclock.S
@@ -16,10 +16,10 @@
#include <mach/hardware.h>
#include <mach/at91_ramc.h>

+#define SRAMC_SELF_FRESH_ACTIVE 0x01
+#define SRAMC_SELF_FRESH_EXIT 0x00
+
pmc .req r0
-sdramc .req r1
-ramc1 .req r2
-memctrl .req r3
tmp1 .req r4
tmp2 .req r5

@@ -73,78 +73,17 @@ ENTRY(at91_slow_clock)
mov tmp1, #0
mcr p15, 0, tmp1, c7, c10, 4

- cmp memctrl, #AT91_MEMCTRL_MC
- bne ddr_sr_enable
+ str r0, .pmc_base
+ str r1, .sramc_base
+ str r2, .sramc1_base
+ str r3, .memtype

- /*
- * at91rm9200 Memory controller
- */
- /* Put SDRAM in self-refresh mode */
- mov tmp1, #1
- str tmp1, [sdramc, #AT91RM9200_SDRAMC_SRR]
- b sdr_sr_done
+ /* Active the self-refresh mode */
+ mov r0, #SRAMC_SELF_FRESH_ACTIVE
+ bl at91_sramc_self_refresh

- /*
- * DDRSDR Memory controller
- */
-ddr_sr_enable:
- cmp memctrl, #AT91_MEMCTRL_DDRSDR
- bne sdr_sr_enable
+ ldr pmc, .pmc_base

- /* LPDDR1 --> force DDR2 mode during self-refresh */
- ldr tmp1, [sdramc, #AT91_DDRSDRC_MDR]
- str tmp1, .saved_sam9_mdr
- bic tmp1, tmp1, #~AT91_DDRSDRC_MD
- cmp tmp1, #AT91_DDRSDRC_MD_LOW_POWER_DDR
- ldreq tmp1, [sdramc, #AT91_DDRSDRC_MDR]
- biceq tmp1, tmp1, #AT91_DDRSDRC_MD
- orreq tmp1, tmp1, #AT91_DDRSDRC_MD_DDR2
- streq tmp1, [sdramc, #AT91_DDRSDRC_MDR]
-
- /* prepare for DDRAM self-refresh mode */
- ldr tmp1, [sdramc, #AT91_DDRSDRC_LPR]
- str tmp1, .saved_sam9_lpr
- bic tmp1, #AT91_DDRSDRC_LPCB
- orr tmp1, #AT91_DDRSDRC_LPCB_SELF_REFRESH
-
- /* figure out if we use the second ram controller */
- cmp ramc1, #0
- beq ddr_no_2nd_ctrl
-
- ldr tmp2, [ramc1, #AT91_DDRSDRC_MDR]
- str tmp2, .saved_sam9_mdr1
- bic tmp2, tmp2, #~AT91_DDRSDRC_MD
- cmp tmp2, #AT91_DDRSDRC_MD_LOW_POWER_DDR
- ldreq tmp2, [ramc1, #AT91_DDRSDRC_MDR]
- biceq tmp2, tmp2, #AT91_DDRSDRC_MD
- orreq tmp2, tmp2, #AT91_DDRSDRC_MD_DDR2
- streq tmp2, [ramc1, #AT91_DDRSDRC_MDR]
-
- ldr tmp2, [ramc1, #AT91_DDRSDRC_LPR]
- str tmp2, .saved_sam9_lpr1
- bic tmp2, #AT91_DDRSDRC_LPCB
- orr tmp2, #AT91_DDRSDRC_LPCB_SELF_REFRESH
-
- /* Enable DDRAM self-refresh mode */
- str tmp2, [ramc1, #AT91_DDRSDRC_LPR]
-ddr_no_2nd_ctrl:
- str tmp1, [sdramc, #AT91_DDRSDRC_LPR]
-
- b sdr_sr_done
-
- /*
- * SDRAMC Memory controller
- */
-sdr_sr_enable:
- /* Enable SDRAM self-refresh mode */
- ldr tmp1, [sdramc, #AT91_SDRAMC_LPR]
- str tmp1, .saved_sam9_lpr
-
- bic tmp1, #AT91_SDRAMC_LPCB
- orr tmp1, #AT91_SDRAMC_LPCB_SELF_REFRESH
- str tmp1, [sdramc, #AT91_SDRAMC_LPR]
-
-sdr_sr_done:
/* Save Master clock setting */
ldr tmp1, [pmc, #AT91_PMC_MCKR]
str tmp1, .saved_mckr
@@ -195,67 +134,163 @@ sdr_sr_done:
/*
* Restore master clock setting
*/
-2: ldr tmp1, .saved_mckr
+ ldr tmp1, .saved_mckr
str tmp1, [pmc, #AT91_PMC_MCKR]

wait_mckrdy

+ /* Exit the self-refresh mode */
+ mov r0, #SRAMC_SELF_FRESH_EXIT
+ bl at91_sramc_self_refresh
+
+ /* Restore registers, and return */
+ ldmfd sp!, {r4 - r12, pc}
+ENDPROC(at91_slow_clock)
+
+/*
+ * void at91_sramc_self_refresh(unsigned int is_active)
+ *
+ * @input param:
+ * @r0: 1 - active self-refresh mode
+ * 0 - exit self-refresh mode
+ * register usage:
+ * @r1: memory type
+ * @r2: base address of the sram controller
+ */
+
+ENTRY(at91_sramc_self_refresh)
+ ldr r1, .memtype
+ ldr r2, .sramc_base
+
+ cmp r1, #AT91_MEMCTRL_MC
+ bne ddrc_sf
+
/*
* at91rm9200 Memory controller
- * Do nothing - self-refresh is automatically disabled.
*/
- cmp memctrl, #AT91_MEMCTRL_MC
- beq ram_restored
+
+ /*
+ * For exiting the self-refresh mode, do nothing,
+ * automatically exit the self-refresh mode.
+ */
+ tst r0, #SRAMC_SELF_FRESH_ACTIVE
+ beq exit_sramc_sf
+
+ /* Active SDRAM self-refresh mode */
+ mov r3, #1
+ str r3, [r2, #AT91RM9200_SDRAMC_SRR]
+ b exit_sramc_sf
+
+ddrc_sf:
+ cmp r1, #AT91_MEMCTRL_DDRSDR
+ bne sdramc_sf

/*
- * DDRSDR Memory controller
+ * DDR Memory controller
*/
- cmp memctrl, #AT91_MEMCTRL_DDRSDR
- bne sdr_en_restore
+ tst r0, #SRAMC_SELF_FRESH_ACTIVE
+ beq ddrc_exit_sf
+
+ /* LPDDR1 --> force DDR2 mode during self-refresh */
+ ldr r3, [r2, #AT91_DDRSDRC_MDR]
+ str r3, .saved_sam9_mdr
+ bic r3, r3, #~AT91_DDRSDRC_MD
+ cmp r3, #AT91_DDRSDRC_MD_LOW_POWER_DDR
+ ldreq r3, [r2, #AT91_DDRSDRC_MDR]
+ biceq r3, r3, #AT91_DDRSDRC_MD
+ orreq r3, r3, #AT91_DDRSDRC_MD_DDR2
+ streq r3, [r2, #AT91_DDRSDRC_MDR]
+
+ /* Active DDRC self-refresh mode */
+ ldr r3, [r2, #AT91_DDRSDRC_LPR]
+ str r3, .saved_sam9_lpr
+ bic r3, r3, #AT91_DDRSDRC_LPCB
+ orr r3, r3, #AT91_DDRSDRC_LPCB_SELF_REFRESH
+ str r3, [r2, #AT91_DDRSDRC_LPR]
+
+ /* If using the 2nd ddr controller */
+ ldr r2, .sramc1_base
+ cmp r2, #0
+ beq no_2nd_ddrc
+
+ ldr r3, [r2, #AT91_DDRSDRC_MDR]
+ str r3, .saved_sam9_mdr1
+ bic r3, r3, #~AT91_DDRSDRC_MD
+ cmp r3, #AT91_DDRSDRC_MD_LOW_POWER_DDR
+ ldreq r3, [r2, #AT91_DDRSDRC_MDR]
+ biceq r3, r3, #AT91_DDRSDRC_MD
+ orreq r3, r3, #AT91_DDRSDRC_MD_DDR2
+ streq r3, [r2, #AT91_DDRSDRC_MDR]
+
+ ldr r3, [r2, #AT91_DDRSDRC_LPR]
+ str r3, .saved_sam9_lpr1
+ bic r3, r3, #AT91_DDRSDRC_LPCB
+ orr r3, r3, #AT91_DDRSDRC_LPCB_SELF_REFRESH
+
+ /* Active DDRC self-refresh mode */
+ str r3, [r2, #AT91_DDRSDRC_LPR]
+no_2nd_ddrc:
+ b exit_sramc_sf
+
+ddrc_exit_sf:
/* Restore MDR in case of LPDDR1 */
- ldr tmp1, .saved_sam9_mdr
- str tmp1, [sdramc, #AT91_DDRSDRC_MDR]
+ ldr r3, .saved_sam9_mdr
+ str r3, [r2, #AT91_DDRSDRC_MDR]
/* Restore LPR on AT91 with DDRAM */
- ldr tmp1, .saved_sam9_lpr
- str tmp1, [sdramc, #AT91_DDRSDRC_LPR]
+ ldr r3, .saved_sam9_lpr
+ str r3, [r2, #AT91_DDRSDRC_LPR]

- /* if we use the second ram controller */
- cmp ramc1, #0
- ldrne tmp2, .saved_sam9_mdr1
- strne tmp2, [ramc1, #AT91_DDRSDRC_MDR]
- ldrne tmp2, .saved_sam9_lpr1
- strne tmp2, [ramc1, #AT91_DDRSDRC_LPR]
+ /* If using the 2nd ddr controller */
+ ldr r2, .sramc1_base
+ cmp r2, #0
+ ldrne r3, .saved_sam9_mdr1
+ strne r3, [r2, #AT91_DDRSDRC_MDR]
+ ldrne r3, .saved_sam9_lpr1
+ strne r3, [r2, #AT91_DDRSDRC_LPR]

- b ram_restored
+ b exit_sramc_sf

/*
* SDRAMC Memory controller
*/
-sdr_en_restore:
- /* Restore LPR on AT91 with SDRAM */
- ldr tmp1, .saved_sam9_lpr
- str tmp1, [sdramc, #AT91_SDRAMC_LPR]
+sdramc_sf:
+ tst r0, #SRAMC_SELF_FRESH_ACTIVE
+ beq sdramc_exit_sf

-ram_restored:
- /* Restore registers, and return */
- ldmfd sp!, {r4 - r12, pc}
+ /* Active SDRAMC self-refresh mode */
+ ldr r3, [r2, #AT91_SDRAMC_LPR]
+ str r3, .saved_sam9_lpr
+
+ bic r3, r3, #AT91_SDRAMC_LPCB
+ orr r3, r3, #AT91_SDRAMC_LPCB_SELF_REFRESH
+ str r3, [r2, #AT91_SDRAMC_LPR]

+sdramc_exit_sf:
+ ldr r3, .saved_sam9_lpr
+ str r3, [r2, #AT91_SDRAMC_LPR]

+exit_sramc_sf:
+ mov pc, lr
+ENDPROC(at91_sramc_self_refresh)
+
+.pmc_base:
+ .word 0
+.sramc_base:
+ .word 0
+.sramc1_base:
+ .word 0
+.memtype:
+ .word 0
.saved_mckr:
.word 0
-
.saved_pllar:
.word 0
-
.saved_sam9_lpr:
.word 0
-
.saved_sam9_lpr1:
.word 0
-
.saved_sam9_mdr:
.word 0
-
.saved_sam9_mdr1:
.word 0

--
1.7.9.5

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