Merge branch 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git...
[linux-2.6.git] / arch / arm / mach-omap1 / sram.S
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 <mach/io.h>
14 #include <mach/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, #OMAP1_IO_ADDRESS(DPLL_CTL) & 0xff000000
25         orr     r2, r2, #OMAP1_IO_ADDRESS(DPLL_CTL) & 0x00ff0000
26         orr     r2, r2, #OMAP1_IO_ADDRESS(DPLL_CTL) & 0x0000ff00
27
28         mov     r3, #OMAP1_IO_ADDRESS(ARM_CKCTL) & 0xff000000
29         orr     r3, r3, #OMAP1_IO_ADDRESS(ARM_CKCTL) & 0x00ff0000
30         orr     r3, r3, #OMAP1_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