ARM: orion5x: fix use of callee-saved registers in lowloevel_init
The lowlevel_init function uses r4 and r6 without preserving their
values as required by the AAPCS. Use r0 and r2 instead as these
are call-clobbered.
Signed-off-by: Mans Rullgard <mans@mansr.com>
Reviewed-by: Chris Packham <judge.packham@gmail.com>
diff --git a/arch/arm/mach-orion5x/lowlevel_init.S b/arch/arm/mach-orion5x/lowlevel_init.S
index f5c382b..aa3fcf7 100644
--- a/arch/arm/mach-orion5x/lowlevel_init.S
+++ b/arch/arm/mach-orion5x/lowlevel_init.S
@@ -71,67 +71,67 @@
#ifdef CONFIG_SPL_BUILD
- /* Use 'r4 as the base for internal register accesses */
- ldr r4, =ORION5X_REGS_PHY_BASE
+ /* Use 'r2 as the base for internal register accesses */
+ ldr r2, =ORION5X_REGS_PHY_BASE
/* move internal registers from the default 0xD0000000
* to their intended location, defined by SoC */
ldr r3, =0xD0000000
add r3, r3, #0x20000
- str r4, [r3, #0x80]
+ str r2, [r3, #0x80]
/* Use R3 as the base for DRAM registers */
- add r3, r4, #0x01000
+ add r3, r2, #0x01000
/*DDR SDRAM Initialization Control */
- ldr r6, =0x00000001
- str r6, [r3, #0x480]
+ ldr r0, =0x00000001
+ str r0, [r3, #0x480]
/* Use R3 as the base for PCI registers */
- add r3, r4, #0x31000
+ add r3, r2, #0x31000
/* Disable arbiter */
- ldr r6, =0x00000030
- str r6, [r3, #0xd00]
+ ldr r0, =0x00000030
+ str r0, [r3, #0xd00]
/* Use R3 as the base for DRAM registers */
- add r3, r4, #0x01000
+ add r3, r2, #0x01000
/* set all dram windows to 0 */
- mov r6, #0
- str r6, [r3, #0x504]
- str r6, [r3, #0x50C]
- str r6, [r3, #0x514]
- str r6, [r3, #0x51C]
+ mov r0, #0
+ str r0, [r3, #0x504]
+ str r0, [r3, #0x50C]
+ str r0, [r3, #0x514]
+ str r0, [r3, #0x51C]
/* 1) Configure SDRAM */
- ldr r6, =SDRAM_CONFIG
- str r6, [r3, #0x400]
+ ldr r0, =SDRAM_CONFIG
+ str r0, [r3, #0x400]
/* 2) Set SDRAM Control reg */
- ldr r6, =SDRAM_CONTROL
- str r6, [r3, #0x404]
+ ldr r0, =SDRAM_CONTROL
+ str r0, [r3, #0x404]
/* 3) Write SDRAM address control register */
- ldr r6, =SDRAM_ADDR_CTRL
- str r6, [r3, #0x410]
+ ldr r0, =SDRAM_ADDR_CTRL
+ str r0, [r3, #0x410]
/* 4) Write SDRAM bank 0 size register */
- ldr r6, =SDRAM_BANK0_SIZE
- str r6, [r3, #0x504]
+ ldr r0, =SDRAM_BANK0_SIZE
+ str r0, [r3, #0x504]
/* keep other banks disabled */
/* 5) Write SDRAM open pages control register */
- ldr r6, =SDRAM_OPEN_PAGE_EN
- str r6, [r3, #0x414]
+ ldr r0, =SDRAM_OPEN_PAGE_EN
+ str r0, [r3, #0x414]
/* 6) Write SDRAM timing Low register */
- ldr r6, =SDRAM_TIME_CTRL_LOW
- str r6, [r3, #0x408]
+ ldr r0, =SDRAM_TIME_CTRL_LOW
+ str r0, [r3, #0x408]
/* 7) Write SDRAM timing High register */
- ldr r6, =SDRAM_TIME_CTRL_HI
- str r6, [r3, #0x40C]
+ ldr r0, =SDRAM_TIME_CTRL_HI
+ str r0, [r3, #0x40C]
/* 8) Write SDRAM mode register */
/* The CPU must not attempt to change the SDRAM Mode register setting */
@@ -142,73 +142,73 @@
/* and then sets SDRAM Mode register to its new value. */
/* 8.1 write 'nop' to SDRAM operation */
- ldr r6, =SDRAM_OP_NOP
- str r6, [r3, #0x418]
+ ldr r0, =SDRAM_OP_NOP
+ str r0, [r3, #0x418]
/* 8.2 poll SDRAM operation until back in 'normal' mode. */
1:
- ldr r6, [r3, #0x418]
- cmp r6, #0
+ ldr r0, [r3, #0x418]
+ cmp r0, #0
bne 1b
/* 8.3 Now its safe to write new value to SDRAM Mode register */
- ldr r6, =SDRAM_MODE
- str r6, [r3, #0x41C]
+ ldr r0, =SDRAM_MODE
+ str r0, [r3, #0x41C]
/* 8.4 Set new mode */
- ldr r6, =SDRAM_OP_SETMODE
- str r6, [r3, #0x418]
+ ldr r0, =SDRAM_OP_SETMODE
+ str r0, [r3, #0x418]
/* 8.5 poll SDRAM operation until back in 'normal' mode. */
2:
- ldr r6, [r3, #0x418]
- cmp r6, #0
+ ldr r0, [r3, #0x418]
+ cmp r0, #0
bne 2b
/* DDR SDRAM Address/Control Pads Calibration */
- ldr r6, [r3, #0x4C0]
+ ldr r0, [r3, #0x4C0]
/* Set Bit [31] to make the register writable */
- orr r6, r6, #SDRAM_PAD_CTRL_WR_EN
- str r6, [r3, #0x4C0]
+ orr r0, r0, #SDRAM_PAD_CTRL_WR_EN
+ str r0, [r3, #0x4C0]
- bic r6, r6, #SDRAM_PAD_CTRL_WR_EN
- bic r6, r6, #SDRAM_PAD_CTRL_TUNE_EN
- bic r6, r6, #SDRAM_PAD_CTRL_DRVN_MASK
- bic r6, r6, #SDRAM_PAD_CTRL_DRVP_MASK
+ bic r0, r0, #SDRAM_PAD_CTRL_WR_EN
+ bic r0, r0, #SDRAM_PAD_CTRL_TUNE_EN
+ bic r0, r0, #SDRAM_PAD_CTRL_DRVN_MASK
+ bic r0, r0, #SDRAM_PAD_CTRL_DRVP_MASK
/* Get the final N locked value of driving strength [22:17] */
- mov r1, r6
+ mov r1, r0
mov r1, r1, LSL #9
mov r1, r1, LSR #26 /* r1[5:0]<DrvN> = r3[22:17]<LockN> */
orr r1, r1, r1, LSL #6 /* r1[11:6]<DrvP> = r1[5:0]<DrvN> */
/* Write to both <DrvN> bits [5:0] and <DrvP> bits [11:6] */
- orr r6, r6, r1
- str r6, [r3, #0x4C0]
+ orr r0, r0, r1
+ str r0, [r3, #0x4C0]
/* DDR SDRAM Data Pads Calibration */
- ldr r6, [r3, #0x4C4]
+ ldr r0, [r3, #0x4C4]
/* Set Bit [31] to make the register writable */
- orr r6, r6, #SDRAM_PAD_CTRL_WR_EN
- str r6, [r3, #0x4C4]
+ orr r0, r0, #SDRAM_PAD_CTRL_WR_EN
+ str r0, [r3, #0x4C4]
- bic r6, r6, #SDRAM_PAD_CTRL_WR_EN
- bic r6, r6, #SDRAM_PAD_CTRL_TUNE_EN
- bic r6, r6, #SDRAM_PAD_CTRL_DRVN_MASK
- bic r6, r6, #SDRAM_PAD_CTRL_DRVP_MASK
+ bic r0, r0, #SDRAM_PAD_CTRL_WR_EN
+ bic r0, r0, #SDRAM_PAD_CTRL_TUNE_EN
+ bic r0, r0, #SDRAM_PAD_CTRL_DRVN_MASK
+ bic r0, r0, #SDRAM_PAD_CTRL_DRVP_MASK
/* Get the final N locked value of driving strength [22:17] */
- mov r1, r6
+ mov r1, r0
mov r1, r1, LSL #9
mov r1, r1, LSR #26
orr r1, r1, r1, LSL #6 /* r1[5:0] = r3[22:17]<LockN> */
/* Write to both <DrvN> bits [5:0] and <DrvP> bits [11:6] */
- orr r6, r6, r1
+ orr r0, r0, r1
- str r6, [r3, #0x4C4]
+ str r0, [r3, #0x4C4]
/* Implement Guideline (GL# MEM-3) Drive Strength Value */
/* Relevant for: 88F5181-A1/B0/B1 and 88F5281-A0/B0 */
@@ -216,37 +216,37 @@
ldr r1, =DDR1_PAD_STRENGTH_DEFAULT
/* Enable writes to DDR SDRAM Addr/Ctrl Pads Calibration register */
- ldr r6, [r3, #0x4C0]
- orr r6, r6, #SDRAM_PAD_CTRL_WR_EN
- str r6, [r3, #0x4C0]
+ ldr r0, [r3, #0x4C0]
+ orr r0, r0, #SDRAM_PAD_CTRL_WR_EN
+ str r0, [r3, #0x4C0]
/* Correct strength and disable writes again */
- bic r6, r6, #SDRAM_PAD_CTRL_WR_EN
- bic r6, r6, #SDRAM_PAD_CTRL_DRV_STR_MASK
- orr r6, r6, r1
- str r6, [r3, #0x4C0]
+ bic r0, r0, #SDRAM_PAD_CTRL_WR_EN
+ bic r0, r0, #SDRAM_PAD_CTRL_DRV_STR_MASK
+ orr r0, r0, r1
+ str r0, [r3, #0x4C0]
/* Enable writes to DDR SDRAM Data Pads Calibration register */
- ldr r6, [r3, #0x4C4]
- orr r6, r6, #SDRAM_PAD_CTRL_WR_EN
- str r6, [r3, #0x4C4]
+ ldr r0, [r3, #0x4C4]
+ orr r0, r0, #SDRAM_PAD_CTRL_WR_EN
+ str r0, [r3, #0x4C4]
/* Correct strength and disable writes again */
- bic r6, r6, #SDRAM_PAD_CTRL_DRV_STR_MASK
- bic r6, r6, #SDRAM_PAD_CTRL_WR_EN
- orr r6, r6, r1
- str r6, [r3, #0x4C4]
+ bic r0, r0, #SDRAM_PAD_CTRL_DRV_STR_MASK
+ bic r0, r0, #SDRAM_PAD_CTRL_WR_EN
+ orr r0, r0, r1
+ str r0, [r3, #0x4C4]
/* Implement Guideline (GL# MEM-4) DQS Reference Delay Tuning */
/* Relevant for: 88F5181-A1/B0/B1 and 88F5281-A0/B0 */
/* Get the "sample on reset" register for the DDR frequancy */
ldr r3, =0x10000
- ldr r6, [r3, #0x010]
+ ldr r0, [r3, #0x010]
ldr r1, =MSAR_ARMDDRCLCK_MASK
- and r1, r6, r1
+ and r1, r0, r1
- ldr r6, =FTDLL_DDR1_166MHZ
+ ldr r0, =FTDLL_DDR1_166MHZ
cmp r1, #MSAR_ARMDDRCLCK_333_167
beq 3f
cmp r1, #MSAR_ARMDDRCLCK_500_167
@@ -254,7 +254,7 @@
cmp r1, #MSAR_ARMDDRCLCK_667_167
beq 3f
- ldr r6, =FTDLL_DDR1_200MHZ
+ ldr r0, =FTDLL_DDR1_200MHZ
cmp r1, #MSAR_ARMDDRCLCK_400_200_1
beq 3f
cmp r1, #MSAR_ARMDDRCLCK_400_200
@@ -264,21 +264,21 @@
cmp r1, #MSAR_ARMDDRCLCK_800_200
beq 3f
- ldr r6, =0
+ ldr r0, =0
3:
/* Use R3 as the base for DRAM registers */
- add r3, r4, #0x01000
+ add r3, r2, #0x01000
ldr r2, [r3, #0x484]
- orr r2, r2, r6
+ orr r2, r2, r0
str r2, [r3, #0x484]
/* enable for 2 GB DDR; detection should find out real amount */
- sub r6, r6, r6
- str r6, [r3, #0x500]
- ldr r6, =0x7fff0001
- str r6, [r3, #0x504]
+ sub r0, r0, r0
+ str r0, [r3, #0x500]
+ ldr r0, =0x7fff0001
+ str r0, [r3, #0x504]
#endif /* CONFIG_SPL_BUILD */