/*
* 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);
