diff options
Diffstat (limited to 'arch/arm/plat-omap/sram.c')
| -rw-r--r-- | arch/arm/plat-omap/sram.c | 116 |
1 files changed, 116 insertions, 0 deletions
diff --git a/arch/arm/plat-omap/sram.c b/arch/arm/plat-omap/sram.c new file mode 100644 index 000000000000..7719a4062e3a --- /dev/null +++ b/arch/arm/plat-omap/sram.c | |||
| @@ -0,0 +1,116 @@ | |||
| 1 | /* | ||
| 2 | * linux/arch/arm/plat-omap/sram.c | ||
| 3 | * | ||
| 4 | * OMAP SRAM detection and management | ||
| 5 | * | ||
| 6 | * Copyright (C) 2005 Nokia Corporation | ||
| 7 | * Written by Tony Lindgren <tony@atomide.com> | ||
| 8 | * | ||
| 9 | * This program is free software; you can redistribute it and/or modify | ||
| 10 | * it under the terms of the GNU General Public License version 2 as | ||
| 11 | * published by the Free Software Foundation. | ||
| 12 | */ | ||
| 13 | |||
| 14 | #include <linux/config.h> | ||
| 15 | #include <linux/module.h> | ||
| 16 | #include <linux/kernel.h> | ||
| 17 | #include <linux/init.h> | ||
| 18 | |||
| 19 | #include <asm/mach/map.h> | ||
| 20 | #include <asm/io.h> | ||
| 21 | #include <asm/cacheflush.h> | ||
| 22 | |||
| 23 | #include "sram.h" | ||
| 24 | |||
| 25 | #define OMAP1_SRAM_BASE 0xd0000000 | ||
| 26 | #define OMAP1_SRAM_START 0x20000000 | ||
| 27 | #define SRAM_BOOTLOADER_SZ 0x80 | ||
| 28 | |||
| 29 | static unsigned long omap_sram_base; | ||
| 30 | static unsigned long omap_sram_size; | ||
| 31 | static unsigned long omap_sram_ceil; | ||
| 32 | |||
| 33 | /* | ||
| 34 | * The amount of SRAM depends on the core type: | ||
| 35 | * 730 = 200K, 1510 = 512K, 5912 = 256K, 1610 = 16K, 1710 = 16K | ||
| 36 | * Note that we cannot try to test for SRAM here because writes | ||
| 37 | * to secure SRAM will hang the system. Also the SRAM is not | ||
| 38 | * yet mapped at this point. | ||
| 39 | */ | ||
| 40 | void __init omap_detect_sram(void) | ||
| 41 | { | ||
| 42 | omap_sram_base = OMAP1_SRAM_BASE; | ||
| 43 | |||
| 44 | if (cpu_is_omap730()) | ||
| 45 | omap_sram_size = 0x32000; | ||
| 46 | else if (cpu_is_omap1510()) | ||
| 47 | omap_sram_size = 0x80000; | ||
| 48 | else if (cpu_is_omap1610() || cpu_is_omap1621() || cpu_is_omap1710()) | ||
| 49 | omap_sram_size = 0x4000; | ||
| 50 | else if (cpu_is_omap1611()) | ||
| 51 | omap_sram_size = 0x3e800; | ||
| 52 | else { | ||
| 53 | printk(KERN_ERR "Could not detect SRAM size\n"); | ||
| 54 | omap_sram_size = 0x4000; | ||
| 55 | } | ||
| 56 | |||
| 57 | printk(KERN_INFO "SRAM size: 0x%lx\n", omap_sram_size); | ||
| 58 | omap_sram_ceil = omap_sram_base + omap_sram_size; | ||
| 59 | } | ||
| 60 | |||
| 61 | static struct map_desc omap_sram_io_desc[] __initdata = { | ||
| 62 | { OMAP1_SRAM_BASE, OMAP1_SRAM_START, 0, MT_DEVICE } | ||
| 63 | }; | ||
| 64 | |||
| 65 | /* | ||
| 66 | * In order to use last 2kB of SRAM on 1611b, we must round the size | ||
| 67 | * up to multiple of PAGE_SIZE. We cannot use ioremap for SRAM, as | ||
| 68 | * clock init needs SRAM early. | ||
| 69 | */ | ||
| 70 | void __init omap_map_sram(void) | ||
| 71 | { | ||
| 72 | if (omap_sram_size == 0) | ||
| 73 | return; | ||
| 74 | |||
| 75 | omap_sram_io_desc[0].length = (omap_sram_size + PAGE_SIZE-1)/PAGE_SIZE; | ||
| 76 | omap_sram_io_desc[0].length *= PAGE_SIZE; | ||
| 77 | iotable_init(omap_sram_io_desc, ARRAY_SIZE(omap_sram_io_desc)); | ||
| 78 | |||
| 79 | /* | ||
| 80 | * Looks like we need to preserve some bootloader code at the | ||
| 81 | * beginning of SRAM for jumping to flash for reboot to work... | ||
| 82 | */ | ||
| 83 | memset((void *)omap_sram_base + SRAM_BOOTLOADER_SZ, 0, | ||
| 84 | omap_sram_size - SRAM_BOOTLOADER_SZ); | ||
| 85 | } | ||
| 86 | |||
| 87 | static void (*_omap_sram_reprogram_clock)(u32 dpllctl, u32 ckctl) = NULL; | ||
| 88 | |||
| 89 | void omap_sram_reprogram_clock(u32 dpllctl, u32 ckctl) | ||
| 90 | { | ||
| 91 | if (_omap_sram_reprogram_clock == NULL) | ||
| 92 | panic("Cannot use SRAM"); | ||
| 93 | |||
| 94 | return _omap_sram_reprogram_clock(dpllctl, ckctl); | ||
| 95 | } | ||
| 96 | |||
| 97 | void * omap_sram_push(void * start, unsigned long size) | ||
| 98 | { | ||
| 99 | if (size > (omap_sram_ceil - (omap_sram_base + SRAM_BOOTLOADER_SZ))) { | ||
| 100 | printk(KERN_ERR "Not enough space in SRAM\n"); | ||
| 101 | return NULL; | ||
| 102 | } | ||
| 103 | omap_sram_ceil -= size; | ||
| 104 | omap_sram_ceil &= ~0x3; | ||
| 105 | memcpy((void *)omap_sram_ceil, start, size); | ||
| 106 | |||
| 107 | return (void *)omap_sram_ceil; | ||
| 108 | } | ||
| 109 | |||
| 110 | void __init omap_sram_init(void) | ||
| 111 | { | ||
| 112 | omap_detect_sram(); | ||
| 113 | omap_map_sram(); | ||
| 114 | _omap_sram_reprogram_clock = omap_sram_push(sram_reprogram_clock, | ||
| 115 | sram_reprogram_clock_sz); | ||
| 116 | } | ||
