diff options
Diffstat (limited to 'arch/arm/mach-omap1/sram.S')
-rw-r--r-- | arch/arm/mach-omap1/sram.S | 57 |
1 files changed, 57 insertions, 0 deletions
diff --git a/arch/arm/mach-omap1/sram.S b/arch/arm/mach-omap1/sram.S new file mode 100644 index 000000000000..126d252062d7 --- /dev/null +++ b/arch/arm/mach-omap1/sram.S | |||
@@ -0,0 +1,57 @@ | |||
1 | /* | ||
2 | * linux/arch/arm/plat-omap/sram-fn.S | ||
3 | * | ||
4 | * Functions that need to be run in internal SRAM | ||
5 | * | ||
6 | * This program is free software; you can redistribute it and/or modify | ||
7 | * it under the terms of the GNU General Public License version 2 as | ||
8 | * published by the Free Software Foundation. | ||
9 | */ | ||
10 | |||
11 | #include <linux/linkage.h> | ||
12 | #include <asm/assembler.h> | ||
13 | #include <asm/arch/io.h> | ||
14 | #include <asm/hardware.h> | ||
15 | |||
16 | .text | ||
17 | |||
18 | /* | ||
19 | * Reprograms ULPD and CKCTL. | ||
20 | */ | ||
21 | ENTRY(omap1_sram_reprogram_clock) | ||
22 | stmfd sp!, {r0 - r12, lr} @ save registers on stack | ||
23 | |||
24 | mov r2, #IO_ADDRESS(DPLL_CTL) & 0xff000000 | ||
25 | orr r2, r2, #IO_ADDRESS(DPLL_CTL) & 0x00ff0000 | ||
26 | orr r2, r2, #IO_ADDRESS(DPLL_CTL) & 0x0000ff00 | ||
27 | |||
28 | mov r3, #IO_ADDRESS(ARM_CKCTL) & 0xff000000 | ||
29 | orr r3, r3, #IO_ADDRESS(ARM_CKCTL) & 0x00ff0000 | ||
30 | orr r3, r3, #IO_ADDRESS(ARM_CKCTL) & 0x0000ff00 | ||
31 | |||
32 | tst r0, #1 << 4 @ want lock mode? | ||
33 | beq newck @ nope | ||
34 | bic r0, r0, #1 << 4 @ else clear lock bit | ||
35 | strh r0, [r2] @ set dpll into bypass mode | ||
36 | orr r0, r0, #1 << 4 @ set lock bit again | ||
37 | |||
38 | newck: | ||
39 | strh r1, [r3] @ write new ckctl value | ||
40 | strh r0, [r2] @ write new dpll value | ||
41 | |||
42 | mov r4, #0x0700 @ let the clocks settle | ||
43 | orr r4, r4, #0x00ff | ||
44 | delay: sub r4, r4, #1 | ||
45 | cmp r4, #0 | ||
46 | bne delay | ||
47 | |||
48 | lock: ldrh r4, [r2], #0 @ read back dpll value | ||
49 | tst r0, #1 << 4 @ want lock mode? | ||
50 | beq out @ nope | ||
51 | tst r4, #1 << 0 @ dpll rate locked? | ||
52 | beq lock @ try again | ||
53 | |||
54 | out: | ||
55 | ldmfd sp!, {r0 - r12, pc} @ restore regs and return | ||
56 | ENTRY(omap1_sram_reprogram_clock_sz) | ||
57 | .word . - omap1_sram_reprogram_clock | ||