u-boot-brain/drivers/mtd/nand/sunxi_nand_spl.c
Miquel Raynal 6ddbb1e936
spl: nand: sunxi: use PIO instead of DMA
SPL support was first written to support only the earlier generations of
Allwinner SoCs, and was only really enabled on the A13 / GR8. However,
those old SoCs had a DMA engine that has been replaced since the A31 by
another DMA controller that is no longer compatible.

Since the code directly uses that DMA controller, it cannot operate
properly on the later SoCs, while the NAND controller has not changed.

There's two paths forward, the first one would have been to add support
for that DMA controller too, the second to just remove the DMA usage
entirely and rely on PIO.

The later has been chosen because CPU overload at this stage is not an
issue and it makes the driver more generic, and easier to understand.

Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Acked-by: Boris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: Maxime Ripard <maxime.ripard@bootlin.com>
2018-04-03 12:11:43 +02:00

550 lines
14 KiB
C

/*
* Copyright (c) 2014-2015, Antmicro Ltd <www.antmicro.com>
* Copyright (c) 2015, AW-SOM Technologies <www.aw-som.com>
*
* SPDX-License-Identifier: GPL-2.0+
*/
#include <asm/arch/clock.h>
#include <asm/io.h>
#include <common.h>
#include <config.h>
#include <nand.h>
#include <linux/ctype.h>
/* registers */
#define NFC_CTL 0x00000000
#define NFC_ST 0x00000004
#define NFC_INT 0x00000008
#define NFC_TIMING_CTL 0x0000000C
#define NFC_TIMING_CFG 0x00000010
#define NFC_ADDR_LOW 0x00000014
#define NFC_ADDR_HIGH 0x00000018
#define NFC_SECTOR_NUM 0x0000001C
#define NFC_CNT 0x00000020
#define NFC_CMD 0x00000024
#define NFC_RCMD_SET 0x00000028
#define NFC_WCMD_SET 0x0000002C
#define NFC_IO_DATA 0x00000030
#define NFC_ECC_CTL 0x00000034
#define NFC_ECC_ST 0x00000038
#define NFC_DEBUG 0x0000003C
#define NFC_ECC_CNT0 0x00000040
#define NFC_ECC_CNT1 0x00000044
#define NFC_ECC_CNT2 0x00000048
#define NFC_ECC_CNT3 0x0000004C
#define NFC_USER_DATA_BASE 0x00000050
#define NFC_EFNAND_STATUS 0x00000090
#define NFC_SPARE_AREA 0x000000A0
#define NFC_PATTERN_ID 0x000000A4
#define NFC_RAM0_BASE 0x00000400
#define NFC_RAM1_BASE 0x00000800
#define NFC_CTL_EN (1 << 0)
#define NFC_CTL_RESET (1 << 1)
#define NFC_CTL_RAM_METHOD (1 << 14)
#define NFC_CTL_PAGE_SIZE_MASK (0xf << 8)
#define NFC_CTL_PAGE_SIZE(a) ((fls(a) - 11) << 8)
#define NFC_ECC_EN (1 << 0)
#define NFC_ECC_PIPELINE (1 << 3)
#define NFC_ECC_EXCEPTION (1 << 4)
#define NFC_ECC_BLOCK_SIZE (1 << 5)
#define NFC_ECC_RANDOM_EN (1 << 9)
#define NFC_ECC_RANDOM_DIRECTION (1 << 10)
#define NFC_ADDR_NUM_OFFSET 16
#define NFC_SEND_ADDR (1 << 19)
#define NFC_ACCESS_DIR (1 << 20)
#define NFC_DATA_TRANS (1 << 21)
#define NFC_SEND_CMD1 (1 << 22)
#define NFC_WAIT_FLAG (1 << 23)
#define NFC_SEND_CMD2 (1 << 24)
#define NFC_SEQ (1 << 25)
#define NFC_DATA_SWAP_METHOD (1 << 26)
#define NFC_ROW_AUTO_INC (1 << 27)
#define NFC_SEND_CMD3 (1 << 28)
#define NFC_SEND_CMD4 (1 << 29)
#define NFC_RAW_CMD (0 << 30)
#define NFC_ECC_CMD (1 << 30)
#define NFC_PAGE_CMD (2 << 30)
#define NFC_ST_CMD_INT_FLAG (1 << 1)
#define NFC_ST_DMA_INT_FLAG (1 << 2)
#define NFC_ST_CMD_FIFO_STAT (1 << 3)
#define NFC_READ_CMD_OFFSET 0
#define NFC_RANDOM_READ_CMD0_OFFSET 8
#define NFC_RANDOM_READ_CMD1_OFFSET 16
#define NFC_CMD_RNDOUTSTART 0xE0
#define NFC_CMD_RNDOUT 0x05
#define NFC_CMD_READSTART 0x30
struct nfc_config {
int page_size;
int ecc_strength;
int ecc_size;
int addr_cycles;
int nseeds;
bool randomize;
bool valid;
};
/* minimal "boot0" style NAND support for Allwinner A20 */
/* random seed used by linux */
const uint16_t random_seed[128] = {
0x2b75, 0x0bd0, 0x5ca3, 0x62d1, 0x1c93, 0x07e9, 0x2162, 0x3a72,
0x0d67, 0x67f9, 0x1be7, 0x077d, 0x032f, 0x0dac, 0x2716, 0x2436,
0x7922, 0x1510, 0x3860, 0x5287, 0x480f, 0x4252, 0x1789, 0x5a2d,
0x2a49, 0x5e10, 0x437f, 0x4b4e, 0x2f45, 0x216e, 0x5cb7, 0x7130,
0x2a3f, 0x60e4, 0x4dc9, 0x0ef0, 0x0f52, 0x1bb9, 0x6211, 0x7a56,
0x226d, 0x4ea7, 0x6f36, 0x3692, 0x38bf, 0x0c62, 0x05eb, 0x4c55,
0x60f4, 0x728c, 0x3b6f, 0x2037, 0x7f69, 0x0936, 0x651a, 0x4ceb,
0x6218, 0x79f3, 0x383f, 0x18d9, 0x4f05, 0x5c82, 0x2912, 0x6f17,
0x6856, 0x5938, 0x1007, 0x61ab, 0x3e7f, 0x57c2, 0x542f, 0x4f62,
0x7454, 0x2eac, 0x7739, 0x42d4, 0x2f90, 0x435a, 0x2e52, 0x2064,
0x637c, 0x66ad, 0x2c90, 0x0bad, 0x759c, 0x0029, 0x0986, 0x7126,
0x1ca7, 0x1605, 0x386a, 0x27f5, 0x1380, 0x6d75, 0x24c3, 0x0f8e,
0x2b7a, 0x1418, 0x1fd1, 0x7dc1, 0x2d8e, 0x43af, 0x2267, 0x7da3,
0x4e3d, 0x1338, 0x50db, 0x454d, 0x764d, 0x40a3, 0x42e6, 0x262b,
0x2d2e, 0x1aea, 0x2e17, 0x173d, 0x3a6e, 0x71bf, 0x25f9, 0x0a5d,
0x7c57, 0x0fbe, 0x46ce, 0x4939, 0x6b17, 0x37bb, 0x3e91, 0x76db,
};
#define DEFAULT_TIMEOUT_US 100000
static int check_value_inner(int offset, int expected_bits,
int timeout_us, int negation)
{
do {
int val = readl(offset) & expected_bits;
if (negation ? !val : val)
return 1;
udelay(1);
} while (--timeout_us);
return 0;
}
static inline int check_value(int offset, int expected_bits,
int timeout_us)
{
return check_value_inner(offset, expected_bits, timeout_us, 0);
}
static inline int check_value_negated(int offset, int unexpected_bits,
int timeout_us)
{
return check_value_inner(offset, unexpected_bits, timeout_us, 1);
}
static int nand_wait_cmd_fifo_empty(void)
{
if (!check_value_negated(SUNXI_NFC_BASE + NFC_ST, NFC_ST_CMD_FIFO_STAT,
DEFAULT_TIMEOUT_US)) {
printf("nand: timeout waiting for empty cmd FIFO\n");
return -ETIMEDOUT;
}
return 0;
}
static int nand_wait_int(void)
{
if (!check_value(SUNXI_NFC_BASE + NFC_ST, NFC_ST_CMD_INT_FLAG,
DEFAULT_TIMEOUT_US)) {
printf("nand: timeout waiting for interruption\n");
return -ETIMEDOUT;
}
return 0;
}
static int nand_exec_cmd(u32 cmd)
{
int ret;
ret = nand_wait_cmd_fifo_empty();
if (ret)
return ret;
writel(NFC_ST_CMD_INT_FLAG, SUNXI_NFC_BASE + NFC_ST);
writel(cmd, SUNXI_NFC_BASE + NFC_CMD);
return nand_wait_int();
}
void nand_init(void)
{
uint32_t val;
board_nand_init();
val = readl(SUNXI_NFC_BASE + NFC_CTL);
/* enable and reset CTL */
writel(val | NFC_CTL_EN | NFC_CTL_RESET,
SUNXI_NFC_BASE + NFC_CTL);
if (!check_value_negated(SUNXI_NFC_BASE + NFC_CTL,
NFC_CTL_RESET, DEFAULT_TIMEOUT_US)) {
printf("Couldn't initialize nand\n");
}
/* reset NAND */
nand_exec_cmd(NFC_SEND_CMD1 | NFC_WAIT_FLAG | NAND_CMD_RESET);
}
static void nand_apply_config(const struct nfc_config *conf)
{
u32 val;
nand_wait_cmd_fifo_empty();
val = readl(SUNXI_NFC_BASE + NFC_CTL);
val &= ~NFC_CTL_PAGE_SIZE_MASK;
writel(val | NFC_CTL_RAM_METHOD | NFC_CTL_PAGE_SIZE(conf->page_size),
SUNXI_NFC_BASE + NFC_CTL);
writel(conf->ecc_size, SUNXI_NFC_BASE + NFC_CNT);
writel(conf->page_size, SUNXI_NFC_BASE + NFC_SPARE_AREA);
}
static int nand_load_page(const struct nfc_config *conf, u32 offs)
{
int page = offs / conf->page_size;
writel((NFC_CMD_RNDOUTSTART << NFC_RANDOM_READ_CMD1_OFFSET) |
(NFC_CMD_RNDOUT << NFC_RANDOM_READ_CMD0_OFFSET) |
(NFC_CMD_READSTART << NFC_READ_CMD_OFFSET),
SUNXI_NFC_BASE + NFC_RCMD_SET);
writel(((page & 0xFFFF) << 16), SUNXI_NFC_BASE + NFC_ADDR_LOW);
writel((page >> 16) & 0xFF, SUNXI_NFC_BASE + NFC_ADDR_HIGH);
return nand_exec_cmd(NFC_SEND_CMD1 | NFC_SEND_CMD2 | NFC_RAW_CMD |
NFC_SEND_ADDR | NFC_WAIT_FLAG |
((conf->addr_cycles - 1) << NFC_ADDR_NUM_OFFSET));
}
static int nand_change_column(u16 column)
{
int ret;
writel((NFC_CMD_RNDOUTSTART << NFC_RANDOM_READ_CMD1_OFFSET) |
(NFC_CMD_RNDOUT << NFC_RANDOM_READ_CMD0_OFFSET) |
(NFC_CMD_RNDOUTSTART << NFC_READ_CMD_OFFSET),
SUNXI_NFC_BASE + NFC_RCMD_SET);
writel(column, SUNXI_NFC_BASE + NFC_ADDR_LOW);
ret = nand_exec_cmd(NFC_SEND_CMD1 | NFC_SEND_CMD2 | NFC_RAW_CMD |
(1 << NFC_ADDR_NUM_OFFSET) | NFC_SEND_ADDR |
NFC_CMD_RNDOUT);
if (ret)
return ret;
/* Ensure tCCS has passed before reading data */
udelay(1);
return 0;
}
static const int ecc_bytes[] = {32, 46, 54, 60, 74, 88, 102, 110, 116};
static int nand_read_page(const struct nfc_config *conf, u32 offs,
void *dest, int len)
{
int nsectors = len / conf->ecc_size;
u16 rand_seed = 0;
int oob_chunk_sz = ecc_bytes[conf->ecc_strength];
int page = offs / conf->page_size;
u32 ecc_st;
int i;
if (offs % conf->page_size || len % conf->ecc_size ||
len > conf->page_size || len < 0)
return -EINVAL;
/* Choose correct seed if randomized */
if (conf->randomize)
rand_seed = random_seed[page % conf->nseeds];
/* Retrieve data from SRAM (PIO) */
for (i = 0; i < nsectors; i++) {
int data_off = i * conf->ecc_size;
int oob_off = conf->page_size + (i * oob_chunk_sz);
u8 *data = dest + data_off;
/* Clear ECC status and restart ECC engine */
writel(0, SUNXI_NFC_BASE + NFC_ECC_ST);
writel((rand_seed << 16) | (conf->ecc_strength << 12) |
(conf->randomize ? NFC_ECC_RANDOM_EN : 0) |
(conf->ecc_size == 512 ? NFC_ECC_BLOCK_SIZE : 0) |
NFC_ECC_EN | NFC_ECC_EXCEPTION,
SUNXI_NFC_BASE + NFC_ECC_CTL);
/* Move the data in SRAM */
nand_change_column(data_off);
writel(conf->ecc_size, SUNXI_NFC_BASE + NFC_CNT);
nand_exec_cmd(NFC_DATA_TRANS);
/*
* Let the ECC engine consume the ECC bytes and possibly correct
* the data.
*/
nand_change_column(oob_off);
nand_exec_cmd(NFC_DATA_TRANS | NFC_ECC_CMD);
/* Get the ECC status */
ecc_st = readl(SUNXI_NFC_BASE + NFC_ECC_ST);
/* ECC error detected. */
if (ecc_st & 0xffff)
return -EIO;
/*
* Return 1 if the first chunk is empty (needed for
* configuration detection).
*/
if (!i && (ecc_st & 0x10000))
return 1;
/* Retrieve the data from SRAM */
memcpy_fromio(data, SUNXI_NFC_BASE + NFC_RAM0_BASE,
conf->ecc_size);
/* Stop the ECC engine */
writel(readl(SUNXI_NFC_BASE + NFC_ECC_CTL) & ~NFC_ECC_EN,
SUNXI_NFC_BASE + NFC_ECC_CTL);
if (data_off + conf->ecc_size >= len)
break;
}
return 0;
}
static int nand_max_ecc_strength(struct nfc_config *conf)
{
int max_oobsize, max_ecc_bytes;
int nsectors = conf->page_size / conf->ecc_size;
int i;
/*
* ECC strength is limited by the size of the OOB area which is
* correlated with the page size.
*/
switch (conf->page_size) {
case 2048:
max_oobsize = 64;
break;
case 4096:
max_oobsize = 256;
break;
case 8192:
max_oobsize = 640;
break;
case 16384:
max_oobsize = 1664;
break;
default:
return -EINVAL;
}
max_ecc_bytes = max_oobsize / nsectors;
for (i = 0; i < ARRAY_SIZE(ecc_bytes); i++) {
if (ecc_bytes[i] > max_ecc_bytes)
break;
}
if (!i)
return -EINVAL;
return i - 1;
}
static int nand_detect_ecc_config(struct nfc_config *conf, u32 offs,
void *dest)
{
/* NAND with pages > 4k will likely require 1k sector size. */
int min_ecc_size = conf->page_size > 4096 ? 1024 : 512;
int page = offs / conf->page_size;
int ret;
/*
* In most cases, 1k sectors are preferred over 512b ones, start
* testing this config first.
*/
for (conf->ecc_size = 1024; conf->ecc_size >= min_ecc_size;
conf->ecc_size >>= 1) {
int max_ecc_strength = nand_max_ecc_strength(conf);
nand_apply_config(conf);
/*
* We are starting from the maximum ECC strength because
* most of the time NAND vendors provide an OOB area that
* barely meets the ECC requirements.
*/
for (conf->ecc_strength = max_ecc_strength;
conf->ecc_strength >= 0;
conf->ecc_strength--) {
conf->randomize = false;
if (nand_change_column(0))
return -EIO;
/*
* Only read the first sector to speedup detection.
*/
ret = nand_read_page(conf, offs, dest, conf->ecc_size);
if (!ret) {
return 0;
} else if (ret > 0) {
/*
* If page is empty we can't deduce anything
* about the ECC config => stop the detection.
*/
return -EINVAL;
}
conf->randomize = true;
conf->nseeds = ARRAY_SIZE(random_seed);
do {
if (nand_change_column(0))
return -EIO;
if (!nand_read_page(conf, offs, dest,
conf->ecc_size))
return 0;
/*
* Find the next ->nseeds value that would
* change the randomizer seed for the page
* we're trying to read.
*/
while (conf->nseeds >= 16) {
int seed = page % conf->nseeds;
conf->nseeds >>= 1;
if (seed != page % conf->nseeds)
break;
}
} while (conf->nseeds >= 16);
}
}
return -EINVAL;
}
static int nand_detect_config(struct nfc_config *conf, u32 offs, void *dest)
{
if (conf->valid)
return 0;
/*
* Modern NANDs are more likely than legacy ones, so we start testing
* with 5 address cycles.
*/
for (conf->addr_cycles = 5;
conf->addr_cycles >= 4;
conf->addr_cycles--) {
int max_page_size = conf->addr_cycles == 4 ? 2048 : 16384;
/*
* Ignoring 1k pages cause I'm not even sure this case exist
* in the real world.
*/
for (conf->page_size = 2048; conf->page_size <= max_page_size;
conf->page_size <<= 1) {
if (nand_load_page(conf, offs))
return -1;
if (!nand_detect_ecc_config(conf, offs, dest)) {
conf->valid = true;
return 0;
}
}
}
return -EINVAL;
}
static int nand_read_buffer(struct nfc_config *conf, uint32_t offs,
unsigned int size, void *dest)
{
int first_seed = 0, page, ret;
size = ALIGN(size, conf->page_size);
page = offs / conf->page_size;
if (conf->randomize)
first_seed = page % conf->nseeds;
for (; size; size -= conf->page_size) {
if (nand_load_page(conf, offs))
return -1;
ret = nand_read_page(conf, offs, dest, conf->page_size);
/*
* The ->nseeds value should be equal to the number of pages
* in an eraseblock. Since we don't know this information in
* advance we might have picked a wrong value.
*/
if (ret < 0 && conf->randomize) {
int cur_seed = page % conf->nseeds;
/*
* We already tried all the seed values => we are
* facing a real corruption.
*/
if (cur_seed < first_seed)
return -EIO;
/* Try to adjust ->nseeds and read the page again... */
conf->nseeds = cur_seed;
if (nand_change_column(0))
return -EIO;
/* ... it still fails => it's a real corruption. */
if (nand_read_page(conf, offs, dest, conf->page_size))
return -EIO;
} else if (ret && conf->randomize) {
memset(dest, 0xff, conf->page_size);
}
page++;
offs += conf->page_size;
dest += conf->page_size;
}
return 0;
}
int nand_spl_load_image(uint32_t offs, unsigned int size, void *dest)
{
static struct nfc_config conf = { };
int ret;
ret = nand_detect_config(&conf, offs, dest);
if (ret)
return ret;
return nand_read_buffer(&conf, offs, size, dest);
}
void nand_deselect(void)
{
struct sunxi_ccm_reg *const ccm =
(struct sunxi_ccm_reg *)SUNXI_CCM_BASE;
clrbits_le32(&ccm->ahb_gate0, (CLK_GATE_OPEN << AHB_GATE_OFFSET_NAND0));
#ifdef CONFIG_MACH_SUN9I
clrbits_le32(&ccm->ahb_gate1, (1 << AHB_GATE_OFFSET_DMA));
#else
clrbits_le32(&ccm->ahb_gate0, (1 << AHB_GATE_OFFSET_DMA));
#endif
clrbits_le32(&ccm->nand0_clk_cfg, CCM_NAND_CTRL_ENABLE | AHB_DIV_1);
}