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Diffstat (limited to 'arch/ppc64/kernel/pmac_nvram.c')
-rw-r--r--arch/ppc64/kernel/pmac_nvram.c495
1 files changed, 495 insertions, 0 deletions
diff --git a/arch/ppc64/kernel/pmac_nvram.c b/arch/ppc64/kernel/pmac_nvram.c
new file mode 100644
index 00000000000..e32a902236e
--- /dev/null
+++ b/arch/ppc64/kernel/pmac_nvram.c
@@ -0,0 +1,495 @@
+/*
+ * arch/ppc/platforms/pmac_nvram.c
+ *
+ * Copyright (C) 2002 Benjamin Herrenschmidt (benh@kernel.crashing.org)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ *
+ * Todo: - add support for the OF persistent properties
+ */
+#include <linux/config.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/stddef.h>
+#include <linux/string.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/delay.h>
+#include <linux/errno.h>
+#include <linux/bootmem.h>
+#include <linux/completion.h>
+#include <linux/spinlock.h>
+#include <asm/sections.h>
+#include <asm/io.h>
+#include <asm/system.h>
+#include <asm/prom.h>
+#include <asm/machdep.h>
+#include <asm/nvram.h>
+
+#define DEBUG
+
+#ifdef DEBUG
+#define DBG(x...) printk(x)
+#else
+#define DBG(x...)
+#endif
+
+#define NVRAM_SIZE 0x2000 /* 8kB of non-volatile RAM */
+
+#define CORE99_SIGNATURE 0x5a
+#define CORE99_ADLER_START 0x14
+
+/* On Core99, nvram is either a sharp, a micron or an AMD flash */
+#define SM_FLASH_STATUS_DONE 0x80
+#define SM_FLASH_STATUS_ERR 0x38
+
+#define SM_FLASH_CMD_ERASE_CONFIRM 0xd0
+#define SM_FLASH_CMD_ERASE_SETUP 0x20
+#define SM_FLASH_CMD_RESET 0xff
+#define SM_FLASH_CMD_WRITE_SETUP 0x40
+#define SM_FLASH_CMD_CLEAR_STATUS 0x50
+#define SM_FLASH_CMD_READ_STATUS 0x70
+
+/* CHRP NVRAM header */
+struct chrp_header {
+ u8 signature;
+ u8 cksum;
+ u16 len;
+ char name[12];
+ u8 data[0];
+};
+
+struct core99_header {
+ struct chrp_header hdr;
+ u32 adler;
+ u32 generation;
+ u32 reserved[2];
+};
+
+/*
+ * Read and write the non-volatile RAM on PowerMacs and CHRP machines.
+ */
+static volatile unsigned char *nvram_data;
+static int core99_bank = 0;
+// XXX Turn that into a sem
+static DEFINE_SPINLOCK(nv_lock);
+
+extern int system_running;
+
+static int (*core99_write_bank)(int bank, u8* datas);
+static int (*core99_erase_bank)(int bank);
+
+static char *nvram_image __pmacdata;
+
+
+static ssize_t __pmac core99_nvram_read(char *buf, size_t count, loff_t *index)
+{
+ int i;
+
+ if (nvram_image == NULL)
+ return -ENODEV;
+ if (*index > NVRAM_SIZE)
+ return 0;
+
+ i = *index;
+ if (i + count > NVRAM_SIZE)
+ count = NVRAM_SIZE - i;
+
+ memcpy(buf, &nvram_image[i], count);
+ *index = i + count;
+ return count;
+}
+
+static ssize_t __pmac core99_nvram_write(char *buf, size_t count, loff_t *index)
+{
+ int i;
+
+ if (nvram_image == NULL)
+ return -ENODEV;
+ if (*index > NVRAM_SIZE)
+ return 0;
+
+ i = *index;
+ if (i + count > NVRAM_SIZE)
+ count = NVRAM_SIZE - i;
+
+ memcpy(&nvram_image[i], buf, count);
+ *index = i + count;
+ return count;
+}
+
+static ssize_t __pmac core99_nvram_size(void)
+{
+ if (nvram_image == NULL)
+ return -ENODEV;
+ return NVRAM_SIZE;
+}
+
+static u8 __pmac chrp_checksum(struct chrp_header* hdr)
+{
+ u8 *ptr;
+ u16 sum = hdr->signature;
+ for (ptr = (u8 *)&hdr->len; ptr < hdr->data; ptr++)
+ sum += *ptr;
+ while (sum > 0xFF)
+ sum = (sum & 0xFF) + (sum>>8);
+ return sum;
+}
+
+static u32 __pmac core99_calc_adler(u8 *buffer)
+{
+ int cnt;
+ u32 low, high;
+
+ buffer += CORE99_ADLER_START;
+ low = 1;
+ high = 0;
+ for (cnt=0; cnt<(NVRAM_SIZE-CORE99_ADLER_START); cnt++) {
+ if ((cnt % 5000) == 0) {
+ high %= 65521UL;
+ high %= 65521UL;
+ }
+ low += buffer[cnt];
+ high += low;
+ }
+ low %= 65521UL;
+ high %= 65521UL;
+
+ return (high << 16) | low;
+}
+
+static u32 __pmac core99_check(u8* datas)
+{
+ struct core99_header* hdr99 = (struct core99_header*)datas;
+
+ if (hdr99->hdr.signature != CORE99_SIGNATURE) {
+ DBG("Invalid signature\n");
+ return 0;
+ }
+ if (hdr99->hdr.cksum != chrp_checksum(&hdr99->hdr)) {
+ DBG("Invalid checksum\n");
+ return 0;
+ }
+ if (hdr99->adler != core99_calc_adler(datas)) {
+ DBG("Invalid adler\n");
+ return 0;
+ }
+ return hdr99->generation;
+}
+
+static int __pmac sm_erase_bank(int bank)
+{
+ int stat, i;
+ unsigned long timeout;
+
+ u8* base = (u8 *)nvram_data + core99_bank*NVRAM_SIZE;
+
+ DBG("nvram: Sharp/Micron Erasing bank %d...\n", bank);
+
+ out_8(base, SM_FLASH_CMD_ERASE_SETUP);
+ out_8(base, SM_FLASH_CMD_ERASE_CONFIRM);
+ timeout = 0;
+ do {
+ if (++timeout > 1000000) {
+ printk(KERN_ERR "nvram: Sharp/Miron flash erase timeout !\n");
+ break;
+ }
+ out_8(base, SM_FLASH_CMD_READ_STATUS);
+ stat = in_8(base);
+ } while (!(stat & SM_FLASH_STATUS_DONE));
+
+ out_8(base, SM_FLASH_CMD_CLEAR_STATUS);
+ out_8(base, SM_FLASH_CMD_RESET);
+
+ for (i=0; i<NVRAM_SIZE; i++)
+ if (base[i] != 0xff) {
+ printk(KERN_ERR "nvram: Sharp/Micron flash erase failed !\n");
+ return -ENXIO;
+ }
+ return 0;
+}
+
+static int __pmac sm_write_bank(int bank, u8* datas)
+{
+ int i, stat = 0;
+ unsigned long timeout;
+
+ u8* base = (u8 *)nvram_data + core99_bank*NVRAM_SIZE;
+
+ DBG("nvram: Sharp/Micron Writing bank %d...\n", bank);
+
+ for (i=0; i<NVRAM_SIZE; i++) {
+ out_8(base+i, SM_FLASH_CMD_WRITE_SETUP);
+ udelay(1);
+ out_8(base+i, datas[i]);
+ timeout = 0;
+ do {
+ if (++timeout > 1000000) {
+ printk(KERN_ERR "nvram: Sharp/Micron flash write timeout !\n");
+ break;
+ }
+ out_8(base, SM_FLASH_CMD_READ_STATUS);
+ stat = in_8(base);
+ } while (!(stat & SM_FLASH_STATUS_DONE));
+ if (!(stat & SM_FLASH_STATUS_DONE))
+ break;
+ }
+ out_8(base, SM_FLASH_CMD_CLEAR_STATUS);
+ out_8(base, SM_FLASH_CMD_RESET);
+ for (i=0; i<NVRAM_SIZE; i++)
+ if (base[i] != datas[i]) {
+ printk(KERN_ERR "nvram: Sharp/Micron flash write failed !\n");
+ return -ENXIO;
+ }
+ return 0;
+}
+
+static int __pmac amd_erase_bank(int bank)
+{
+ int i, stat = 0;
+ unsigned long timeout;
+
+ u8* base = (u8 *)nvram_data + core99_bank*NVRAM_SIZE;
+
+ DBG("nvram: AMD Erasing bank %d...\n", bank);
+
+ /* Unlock 1 */
+ out_8(base+0x555, 0xaa);
+ udelay(1);
+ /* Unlock 2 */
+ out_8(base+0x2aa, 0x55);
+ udelay(1);
+
+ /* Sector-Erase */
+ out_8(base+0x555, 0x80);
+ udelay(1);
+ out_8(base+0x555, 0xaa);
+ udelay(1);
+ out_8(base+0x2aa, 0x55);
+ udelay(1);
+ out_8(base, 0x30);
+ udelay(1);
+
+ timeout = 0;
+ do {
+ if (++timeout > 1000000) {
+ printk(KERN_ERR "nvram: AMD flash erase timeout !\n");
+ break;
+ }
+ stat = in_8(base) ^ in_8(base);
+ } while (stat != 0);
+
+ /* Reset */
+ out_8(base, 0xf0);
+ udelay(1);
+
+ for (i=0; i<NVRAM_SIZE; i++)
+ if (base[i] != 0xff) {
+ printk(KERN_ERR "nvram: AMD flash erase failed !\n");
+ return -ENXIO;
+ }
+ return 0;
+}
+
+static int __pmac amd_write_bank(int bank, u8* datas)
+{
+ int i, stat = 0;
+ unsigned long timeout;
+
+ u8* base = (u8 *)nvram_data + core99_bank*NVRAM_SIZE;
+
+ DBG("nvram: AMD Writing bank %d...\n", bank);
+
+ for (i=0; i<NVRAM_SIZE; i++) {
+ /* Unlock 1 */
+ out_8(base+0x555, 0xaa);
+ udelay(1);
+ /* Unlock 2 */
+ out_8(base+0x2aa, 0x55);
+ udelay(1);
+
+ /* Write single word */
+ out_8(base+0x555, 0xa0);
+ udelay(1);
+ out_8(base+i, datas[i]);
+
+ timeout = 0;
+ do {
+ if (++timeout > 1000000) {
+ printk(KERN_ERR "nvram: AMD flash write timeout !\n");
+ break;
+ }
+ stat = in_8(base) ^ in_8(base);
+ } while (stat != 0);
+ if (stat != 0)
+ break;
+ }
+
+ /* Reset */
+ out_8(base, 0xf0);
+ udelay(1);
+
+ for (i=0; i<NVRAM_SIZE; i++)
+ if (base[i] != datas[i]) {
+ printk(KERN_ERR "nvram: AMD flash write failed !\n");
+ return -ENXIO;
+ }
+ return 0;
+}
+
+
+static int __pmac core99_nvram_sync(void)
+{
+ struct core99_header* hdr99;
+ unsigned long flags;
+
+ spin_lock_irqsave(&nv_lock, flags);
+ if (!memcmp(nvram_image, (u8*)nvram_data + core99_bank*NVRAM_SIZE,
+ NVRAM_SIZE))
+ goto bail;
+
+ DBG("Updating nvram...\n");
+
+ hdr99 = (struct core99_header*)nvram_image;
+ hdr99->generation++;
+ hdr99->hdr.signature = CORE99_SIGNATURE;
+ hdr99->hdr.cksum = chrp_checksum(&hdr99->hdr);
+ hdr99->adler = core99_calc_adler(nvram_image);
+ core99_bank = core99_bank ? 0 : 1;
+ if (core99_erase_bank)
+ if (core99_erase_bank(core99_bank)) {
+ printk("nvram: Error erasing bank %d\n", core99_bank);
+ goto bail;
+ }
+ if (core99_write_bank)
+ if (core99_write_bank(core99_bank, nvram_image))
+ printk("nvram: Error writing bank %d\n", core99_bank);
+ bail:
+ spin_unlock_irqrestore(&nv_lock, flags);
+
+ return 0;
+}
+
+int __init pmac_nvram_init(void)
+{
+ struct device_node *dp;
+ u32 gen_bank0, gen_bank1;
+ int i;
+
+ dp = find_devices("nvram");
+ if (dp == NULL) {
+ printk(KERN_ERR "Can't find NVRAM device\n");
+ return -ENODEV;
+ }
+ if (!device_is_compatible(dp, "nvram,flash")) {
+ printk(KERN_ERR "Incompatible type of NVRAM\n");
+ return -ENXIO;
+ }
+
+ nvram_image = alloc_bootmem(NVRAM_SIZE);
+ if (nvram_image == NULL) {
+ printk(KERN_ERR "nvram: can't allocate ram image\n");
+ return -ENOMEM;
+ }
+ nvram_data = ioremap(dp->addrs[0].address, NVRAM_SIZE*2);
+
+ DBG("nvram: Checking bank 0...\n");
+
+ gen_bank0 = core99_check((u8 *)nvram_data);
+ gen_bank1 = core99_check((u8 *)nvram_data + NVRAM_SIZE);
+ core99_bank = (gen_bank0 < gen_bank1) ? 1 : 0;
+
+ DBG("nvram: gen0=%d, gen1=%d\n", gen_bank0, gen_bank1);
+ DBG("nvram: Active bank is: %d\n", core99_bank);
+
+ for (i=0; i<NVRAM_SIZE; i++)
+ nvram_image[i] = nvram_data[i + core99_bank*NVRAM_SIZE];
+
+ ppc_md.nvram_read = core99_nvram_read;
+ ppc_md.nvram_write = core99_nvram_write;
+ ppc_md.nvram_size = core99_nvram_size;
+ ppc_md.nvram_sync = core99_nvram_sync;
+
+ /*
+ * Maybe we could be smarter here though making an exclusive list
+ * of known flash chips is a bit nasty as older OF didn't provide us
+ * with a useful "compatible" entry. A solution would be to really
+ * identify the chip using flash id commands and base ourselves on
+ * a list of known chips IDs
+ */
+ if (device_is_compatible(dp, "amd-0137")) {
+ core99_erase_bank = amd_erase_bank;
+ core99_write_bank = amd_write_bank;
+ } else {
+ core99_erase_bank = sm_erase_bank;
+ core99_write_bank = sm_write_bank;
+ }
+
+ return 0;
+}
+
+int __pmac pmac_get_partition(int partition)
+{
+ struct nvram_partition *part;
+ const char *name;
+ int sig;
+
+ switch(partition) {
+ case pmac_nvram_OF:
+ name = "common";
+ sig = NVRAM_SIG_SYS;
+ break;
+ case pmac_nvram_XPRAM:
+ name = "APL,MacOS75";
+ sig = NVRAM_SIG_OS;
+ break;
+ case pmac_nvram_NR:
+ default:
+ /* Oldworld stuff */
+ return -ENODEV;
+ }
+
+ part = nvram_find_partition(sig, name);
+ if (part == NULL)
+ return 0;
+
+ return part->index;
+}
+
+u8 __pmac pmac_xpram_read(int xpaddr)
+{
+ int offset = pmac_get_partition(pmac_nvram_XPRAM);
+ loff_t index;
+ u8 buf;
+ ssize_t count;
+
+ if (offset < 0 || xpaddr < 0 || xpaddr > 0x100)
+ return 0xff;
+ index = offset + xpaddr;
+
+ count = ppc_md.nvram_read(&buf, 1, &index);
+ if (count != 1)
+ return 0xff;
+ return buf;
+}
+
+void __pmac pmac_xpram_write(int xpaddr, u8 data)
+{
+ int offset = pmac_get_partition(pmac_nvram_XPRAM);
+ loff_t index;
+ u8 buf;
+
+ if (offset < 0 || xpaddr < 0 || xpaddr > 0x100)
+ return;
+ index = offset + xpaddr;
+ buf = data;
+
+ ppc_md.nvram_write(&buf, 1, &index);
+}
+
+EXPORT_SYMBOL(pmac_get_partition);
+EXPORT_SYMBOL(pmac_xpram_read);
+EXPORT_SYMBOL(pmac_xpram_write);