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authorThomas Petazzoni <thomas.petazzoni@free-electrons.com>2017-08-15 22:52:44 +0200
committerTom Rini <trini@konsulko.com>2017-08-26 14:56:10 -0400
commitc25c4fd0104e8a6695783e41f896ce5f288a6a70 (patch)
tree9719944339bd7c63a5bbf9bffb01f5505872f65d /arch/arm/cpu/arm926ejs/spear/spr_lowlevel_init.S
parentfc6adebbc18c1c4d36e80cca0739c96717b733d6 (diff)
board/spear/common: move code to arch/arm/cpu/arm926ejs/spear/
The code in board/spear/common/ is not board-specific but SoC-specific. Therefore, boards from other vendors than "spear" may want to re-use this code, which is currently difficult with the code being placed in board/spear/common/. Since this code really is SoC-specific, this commit moves it to arch/arm/cpu/arm926ejs/spear/, with the rest of the SPEAr related code. Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Diffstat (limited to 'arch/arm/cpu/arm926ejs/spear/spr_lowlevel_init.S')
-rw-r--r--arch/arm/cpu/arm926ejs/spear/spr_lowlevel_init.S174
1 files changed, 174 insertions, 0 deletions
diff --git a/arch/arm/cpu/arm926ejs/spear/spr_lowlevel_init.S b/arch/arm/cpu/arm926ejs/spear/spr_lowlevel_init.S
new file mode 100644
index 0000000000..649488399a
--- /dev/null
+++ b/arch/arm/cpu/arm926ejs/spear/spr_lowlevel_init.S
@@ -0,0 +1,174 @@
+/*
+ * (C) Copyright 2006
+ * Vipin Kumar, ST Micoelectronics, vipin.kumar@st.com.
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#include <config.h>
+
+/*
+ * platform specific initializations are already done in Xloader
+ * Initializations already done include
+ * DDR, PLLs, IP's clock enable and reset release etc
+ */
+.globl lowlevel_init
+lowlevel_init:
+ mov pc, lr
+
+/* void setfreq(unsigned int device, unsigned int frequency) */
+.global setfreq
+setfreq:
+ stmfd sp!,{r14}
+ stmfd sp!,{r0-r12}
+
+ mov r8,sp
+ ldr sp,SRAM_STACK_V
+
+ /* Saving the function arguements for later use */
+ mov r4,r0
+ mov r5,r1
+
+ /* Putting DDR into self refresh */
+ ldr r0,DDR_07_V
+ ldr r1,[r0]
+ ldr r2,DDR_ACTIVE_V
+ bic r1, r1, r2
+ str r1,[r0]
+ ldr r0,DDR_57_V
+ ldr r1,[r0]
+ ldr r2,CYCLES_MASK_V
+ bic r1, r1, r2
+ ldr r2,REFRESH_CYCLES_V
+ orr r1, r1, r2, lsl #16
+ str r1,[r0]
+ ldr r0,DDR_07_V
+ ldr r1,[r0]
+ ldr r2,SREFRESH_MASK_V
+ orr r1, r1, r2
+ str r1,[r0]
+
+ /* flush pipeline */
+ b flush
+ .align 5
+flush:
+ /* Delay to ensure self refresh mode */
+ ldr r0,SREFRESH_DELAY_V
+delay:
+ sub r0,r0,#1
+ cmp r0,#0
+ bne delay
+
+ /* Putting system in slow mode */
+ ldr r0,SCCTRL_V
+ mov r1,#2
+ str r1,[r0]
+
+ /* Changing PLL(1/2) frequency */
+ mov r0,r4
+ mov r1,r5
+
+ cmp r4,#0
+ beq pll1_freq
+
+ /* Change PLL2 (DDR frequency) */
+ ldr r6,PLL2_FREQ_V
+ ldr r7,PLL2_CNTL_V
+ b pll2_freq
+
+pll1_freq:
+ /* Change PLL1 (CPU frequency) */
+ ldr r6,PLL1_FREQ_V
+ ldr r7,PLL1_CNTL_V
+
+pll2_freq:
+ mov r0,r6
+ ldr r1,[r0]
+ ldr r2,PLLFREQ_MASK_V
+ bic r1,r1,r2
+ mov r2,r5,lsr#1
+ orr r1,r1,r2,lsl#24
+ str r1,[r0]
+
+ mov r0,r7
+ ldr r1,P1C0A_V
+ str r1,[r0]
+ ldr r1,P1C0E_V
+ str r1,[r0]
+ ldr r1,P1C06_V
+ str r1,[r0]
+ ldr r1,P1C0E_V
+ str r1,[r0]
+
+lock:
+ ldr r1,[r0]
+ and r1,r1,#1
+ cmp r1,#0
+ beq lock
+
+ /* Putting system back to normal mode */
+ ldr r0,SCCTRL_V
+ mov r1,#4
+ str r1,[r0]
+
+ /* Putting DDR back to normal */
+ ldr r0,DDR_07_V
+ ldr r1,[R0]
+ ldr r2,SREFRESH_MASK_V
+ bic r1, r1, r2
+ str r1,[r0]
+ ldr r2,DDR_ACTIVE_V
+ orr r1, r1, r2
+ str r1,[r0]
+
+ /* Delay to ensure self refresh mode */
+ ldr r0,SREFRESH_DELAY_V
+1:
+ sub r0,r0,#1
+ cmp r0,#0
+ bne 1b
+
+ mov sp,r8
+ /* Resuming back to code */
+ ldmia sp!,{r0-r12}
+ ldmia sp!,{pc}
+
+SCCTRL_V:
+ .word 0xfca00000
+PLL1_FREQ_V:
+ .word 0xfca8000C
+PLL1_CNTL_V:
+ .word 0xfca80008
+PLL2_FREQ_V:
+ .word 0xfca80018
+PLL2_CNTL_V:
+ .word 0xfca80014
+PLLFREQ_MASK_V:
+ .word 0xff000000
+P1C0A_V:
+ .word 0x1C0A
+P1C0E_V:
+ .word 0x1C0E
+P1C06_V:
+ .word 0x1C06
+
+SREFRESH_DELAY_V:
+ .word 0x9999
+SRAM_STACK_V:
+ .word 0xD2800600
+DDR_07_V:
+ .word 0xfc60001c
+DDR_ACTIVE_V:
+ .word 0x01000000
+DDR_57_V:
+ .word 0xfc6000e4
+CYCLES_MASK_V:
+ .word 0xffff0000
+REFRESH_CYCLES_V:
+ .word 0xf0f0
+SREFRESH_MASK_V:
+ .word 0x00010000
+
+.global setfreq_sz
+setfreq_sz:
+ .word setfreq_sz - setfreq