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armv7: Add SPI driver for Exynos.

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The SPI flash driver for Exynos chipset.

Verified to boot on snow/armv7.

Change-Id: I7eef67a9c57f825d09f13ea44c2b59b54345fa7b
Signed-off-by: Hung-Te Lin <hungte@chromium.org>
Reviewed-on: http://review.coreboot.org/2229
Tested-by: build bot (Jenkins)
Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>
This commit is contained in:
Hung-Te Lin
2013-01-30 20:02:02 +08:00
committed by Ronald G. Minnich
parent 6fe0cab205
commit 7e494050d6
3 changed files with 251 additions and 249 deletions
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236
src/cpu/samsung/exynos5-common/spi.c
View File

@@ -1,7 +1,237 @@
#include <cbfs.h>
/*
* Copyright (C) 2011 Samsung Electronics
* Copyright (C) 2013 The Chromium OS Authors. All rights reserved.
*
* See file CREDITS for list of people who contributed to this
* project.
*
* 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.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston,
* MA 02111-1307 USA
*/
/* TODO provide a real SPI driver here for firmware media. */
#include <stdlib.h>
#include <common.h>
#include <console/console.h>
#include <cpu/samsung/exynos5250/gpio.h>
#include <cpu/samsung/exynos5250/clk.h>
#include "spi.h"
#define OM_STAT (0x1f << 1)
#define EXYNOS_BASE_SPI1 ((void *)0x12d30000)
#if defined(CONFIG_DEBUG_SPI) && CONFIG_DEBUG_SPI
# define DEBUG_SPI(x,...) printk(BIOS_DEBUG, "EXYNOS_SPI: " x)
#else
# define DEBUG_SPI(x,...)
#endif
static void exynos_spi_rx_tx(struct exynos_spi *regs, int todo,
void *dinp, void const *doutp, int i)
{
int rx_lvl, tx_lvl;
uint *rxp = (uint *)(dinp + (i * (32 * 1024)));
uint out_bytes, in_bytes;
// TODO In currrent implementation, every read/write must be aligned to
// 4 bytes, otherwise you may get timeout or other unexpected results.
assert(todo % 4 == 0);
out_bytes = in_bytes = todo;
setbits_le32(&regs->ch_cfg, SPI_CH_RST);
clrbits_le32(&regs->ch_cfg, SPI_CH_RST);
writel(((todo * 8) / 32) | SPI_PACKET_CNT_EN, &regs->pkt_cnt);
while (in_bytes) {
uint32_t spi_sts;
int temp;
spi_sts = readl(&regs->spi_sts);
rx_lvl = ((spi_sts >> 15) & 0x7f);
tx_lvl = ((spi_sts >> 6) & 0x7f);
while (tx_lvl < 32 && out_bytes) {
// TODO The "writing" (tx) is not supported now; that's
// why we write garbage to keep driving FIFO clock.
temp = 0xffffffff;
writel(temp, &regs->tx_data);
out_bytes -= 4;
tx_lvl += 4;
}
while (rx_lvl >= 4 && in_bytes) {
temp = readl(&regs->rx_data);
if (rxp)
*rxp++ = temp;
in_bytes -= 4;
rx_lvl -= 4;
}
}
}
int exynos_spi_open(struct exynos_spi *regs)
{
clock_set_rate(PERIPH_ID_SPI1, 50000000); /* set spi clock to 50Mhz */
/* set the spi1 GPIO */
// TODO Some of these should be done in board's bootblock file.
// We should fix-up the mainboard-specific vs. exynos-specific parts in a
// follow-up CL.
// exynos_pinmux_config(PERIPH_ID_SPI1, PINMUX_FLAG_NONE);
gpio_cfg_pin(GPIO_A24, 0x2);
gpio_cfg_pin(GPIO_A25, 0x2);
gpio_cfg_pin(GPIO_A26, 0x2);
gpio_cfg_pin(GPIO_A27, 0x2);
/* set pktcnt and enable it */
writel(4 | SPI_PACKET_CNT_EN, &regs->pkt_cnt);
/* set FB_CLK_SEL */
writel(SPI_FB_DELAY_180, &regs->fb_clk);
/* set CH_WIDTH and BUS_WIDTH as word */
setbits_le32(&regs->mode_cfg,
SPI_MODE_CH_WIDTH_WORD | SPI_MODE_BUS_WIDTH_WORD);
clrbits_le32(&regs->ch_cfg, SPI_CH_CPOL_L); /* CPOL: active high */
/* clear rx and tx channel if set priveously */
clrbits_le32(&regs->ch_cfg, SPI_RX_CH_ON | SPI_TX_CH_ON);
setbits_le32(&regs->swap_cfg,
SPI_RX_SWAP_EN | SPI_RX_BYTE_SWAP | SPI_RX_HWORD_SWAP);
/* do a soft reset */
setbits_le32(&regs->ch_cfg, SPI_CH_RST);
clrbits_le32(&regs->ch_cfg, SPI_CH_RST);
/* now set rx and tx channel ON */
setbits_le32(&regs->ch_cfg, SPI_RX_CH_ON | SPI_TX_CH_ON | SPI_CH_HS_EN);
clrbits_le32(&regs->cs_reg, SPI_SLAVE_SIG_INACT); /* CS low */
return 0;
}
int exynos_spi_read(struct exynos_spi *regs, void *dest, u32 len, u32 off)
{
int upto, todo;
int i;
/* Send read instruction (0x3h) followed by a 24 bit addr */
writel((SF_READ_DATA_CMD << 24) | off, &regs->tx_data);
/* waiting for TX done */
while (!(readl(&regs->spi_sts) & SPI_ST_TX_DONE));
for (upto = 0, i = 0; upto < len; upto += todo, i++) {
todo = MIN(len - upto, (1 << 15));
exynos_spi_rx_tx(regs, todo, dest, (void *)(off), i);
}
setbits_le32(&regs->cs_reg, SPI_SLAVE_SIG_INACT);/* make the CS high */
/*
* Let put controller mode to BYTE as
* SPI driver does not support WORD mode yet
*/
clrbits_le32(&regs->mode_cfg,
SPI_MODE_CH_WIDTH_WORD | SPI_MODE_BUS_WIDTH_WORD);
writel(0, &regs->swap_cfg);
return len;
}
int exynos_spi_close(struct exynos_spi *regs)
{
/*
* Flush spi tx, rx fifos and reset the SPI controller
* and clear rx/tx channel
*/
clrsetbits_le32(&regs->ch_cfg, SPI_CH_HS_EN, SPI_CH_RST);
clrbits_le32(&regs->ch_cfg, SPI_CH_RST);
clrbits_le32(&regs->ch_cfg, SPI_TX_CH_ON | SPI_RX_CH_ON);
return 0;
}
// SPI as CBFS media.
struct exynos_spi_media {
struct exynos_spi *regs;
struct cbfs_simple_buffer buffer;
};
static int exynos_spi_cbfs_open(struct cbfs_media *media) {
struct exynos_spi_media *spi = (struct exynos_spi_media*)media->context;
DEBUG_SPI("exynos_spi_cbfs_open\n");
return exynos_spi_open(spi->regs);
}
static int exynos_spi_cbfs_close(struct cbfs_media *media) {
struct exynos_spi_media *spi = (struct exynos_spi_media*)media->context;
DEBUG_SPI("exynos_spi_cbfs_close\n");
return exynos_spi_close(spi->regs);
}
static size_t exynos_spi_cbfs_read(struct cbfs_media *media, void *dest,
size_t offset, size_t count) {
struct exynos_spi_media *spi = (struct exynos_spi_media*)media->context;
int bytes;
DEBUG_SPI("exynos_spi_cbfs_read(%u)\n", count);
bytes = exynos_spi_read(spi->regs, dest, count, offset);
// Flush and re-open the device.
exynos_spi_close(spi->regs);
exynos_spi_open(spi->regs);
return bytes;
}
static void *exynos_spi_cbfs_map(struct cbfs_media *media, size_t offset,
size_t count) {
struct exynos_spi_media *spi = (struct exynos_spi_media*)media->context;
DEBUG_SPI("exynos_spi_cbfs_map\n");
// See exynos_spi_rx_tx for I/O alignment limitation.
if (count % 4)
count += 4 - (count % 4);
return cbfs_simple_buffer_map(&spi->buffer, media, offset, count);
}
static void *exynos_spi_cbfs_unmap(struct cbfs_media *media,
const void *address) {
struct exynos_spi_media *spi = (struct exynos_spi_media*)media->context;
DEBUG_SPI("exynos_spi_cbfs_unmap\n");
return cbfs_simple_buffer_unmap(&spi->buffer, address);
}
int initialize_exynos_spi_cbfs_media(struct cbfs_media *media,
void *buffer_address,
size_t buffer_size) {
// TODO Replace static variable to support multiple streams.
static struct exynos_spi_media context;
DEBUG_SPI("initialize_exynos_spi_cbfs_media\n");
context.regs = EXYNOS_BASE_SPI1;
context.buffer.allocated = context.buffer.last_allocate = 0;
context.buffer.buffer = buffer_address;
context.buffer.size = buffer_size;
media->context = (void*)&context;
media->open = exynos_spi_cbfs_open;
media->close = exynos_spi_cbfs_close;
media->read = exynos_spi_cbfs_read;
media->map = exynos_spi_cbfs_map;
media->unmap = exynos_spi_cbfs_unmap;
return 0;
}
int init_default_cbfs_media(struct cbfs_media *media) {
return -1;
return initialize_exynos_spi_cbfs_media(
media,
(void*)CONFIG_CBFS_CACHE_ADDRESS,
CONFIG_CBFS_CACHE_SIZE);
}

13
src/cpu/samsung/exynos5-common/spi.h
View File

@@ -22,6 +22,9 @@
#ifndef __ASSEMBLER__
// This driver serves as a CBFS media source.
#include <cbfs.h>
/* SPI peripheral register map; padded to 64KB */
struct exynos_spi {
unsigned int ch_cfg; /* 0x00 */
@@ -85,5 +88,15 @@ struct exynos_spi {
#define SPI_RX_BYTE_SWAP (1 << 6)
#define SPI_RX_HWORD_SWAP (1 << 7)
/* API */
int exynos_spi_open(struct exynos_spi *regs);
int exynos_spi_read(struct exynos_spi *regs, void *dest, u32 len, u32 off);
int exynos_spi_close(struct exynos_spi *regs);
/* Serve as CBFS Media */
int initialize_exynos_spi_cbfs_media(struct cbfs_media *media,
void *buffer_address,
size_t buffer_size);
#endif /* __ASSEMBLER__ */
#endif