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tegra2: spi: Add SPI driver for Tegra2 SOC

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This driver supports SPI on Tegra2, running at 48MHz.

Signed-off-by: Tom Warren <twarren@nvidia.com>
Acked-by: Mike Frysinger <vapier@gentoo.org>
This commit is contained in:
Tom Warren 2011-11-05 09:48:11 +00:00 committed by Albert ARIBAUD
parent 1be0d75973
commit 9112ef8d89
5 changed files with 347 additions and 0 deletions
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1
arch/arm/include/asm/arch-tegra2/tegra2.h
View file

@ -38,6 +38,7 @@
#define NV_PA_APB_UARTC_BASE (NV_PA_APB_MISC_BASE + 0x6200)
#define NV_PA_APB_UARTD_BASE (NV_PA_APB_MISC_BASE + 0x6300)
#define NV_PA_APB_UARTE_BASE (NV_PA_APB_MISC_BASE + 0x6400)
#define TEGRA2_SPI_BASE (NV_PA_APB_MISC_BASE + 0xC380)
#define NV_PA_PMC_BASE 0x7000E400
#define NV_PA_CSITE_BASE 0x70040000

76
arch/arm/include/asm/arch-tegra2/tegra2_spi.h Normal file
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@ -0,0 +1,76 @@
/*
* NVIDIA Tegra2 SPI-FLASH controller
*
* Copyright 2010-2011 NVIDIA Corporation
*
* This software may be used and distributed according to the
* terms of the GNU Public License, Version 2, incorporated
* herein by reference.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* Version 2 as published by the Free Software Foundation.
*
* 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
*/
#ifndef _TEGRA2_SPI_H_
#define _TEGRA2_SPI_H_
#include <asm/types.h>
struct spi_tegra {
u32 command; /* SPI_COMMAND_0 register */
u32 status; /* SPI_STATUS_0 register */
u32 rx_cmp; /* SPI_RX_CMP_0 register */
u32 dma_ctl; /* SPI_DMA_CTL_0 register */
u32 tx_fifo; /* SPI_TX_FIFO_0 register */
u32 rsvd[3]; /* offsets 0x14 to 0x1F reserved */
u32 rx_fifo; /* SPI_RX_FIFO_0 register */
};
#define SPI_CMD_GO (1 << 30)
#define SPI_CMD_ACTIVE_SCLK_SHIFT 26
#define SPI_CMD_ACTIVE_SCLK_MASK (3 << SPI_CMD_ACTIVE_SCLK_SHIFT)
#define SPI_CMD_CK_SDA (1 << 21)
#define SPI_CMD_ACTIVE_SDA_SHIFT 18
#define SPI_CMD_ACTIVE_SDA_MASK (3 << SPI_CMD_ACTIVE_SDA_SHIFT)
#define SPI_CMD_CS_POL (1 << 16)
#define SPI_CMD_TXEN (1 << 15)
#define SPI_CMD_RXEN (1 << 14)
#define SPI_CMD_CS_VAL (1 << 13)
#define SPI_CMD_CS_SOFT (1 << 12)
#define SPI_CMD_CS_DELAY (1 << 9)
#define SPI_CMD_CS3_EN (1 << 8)
#define SPI_CMD_CS2_EN (1 << 7)
#define SPI_CMD_CS1_EN (1 << 6)
#define SPI_CMD_CS0_EN (1 << 5)
#define SPI_CMD_BIT_LENGTH (1 << 4)
#define SPI_CMD_BIT_LENGTH_MASK 0x0000001F
#define SPI_STAT_BSY (1 << 31)
#define SPI_STAT_RDY (1 << 30)
#define SPI_STAT_RXF_FLUSH (1 << 29)
#define SPI_STAT_TXF_FLUSH (1 << 28)
#define SPI_STAT_RXF_UNR (1 << 27)
#define SPI_STAT_TXF_OVF (1 << 26)
#define SPI_STAT_RXF_EMPTY (1 << 25)
#define SPI_STAT_RXF_FULL (1 << 24)
#define SPI_STAT_TXF_EMPTY (1 << 23)
#define SPI_STAT_TXF_FULL (1 << 22)
#define SPI_STAT_SEL_TXRX_N (1 << 16)
#define SPI_STAT_CUR_BLKCNT (1 << 15)
#define SPI_TIMEOUT 1000
#define TEGRA2_SPI_MAX_FREQ 52000000
#endif /* _TEGRA2_SPI_H_ */

4
board/nvidia/common/board.c
View file

@ -31,6 +31,7 @@
#include <asm/arch/clock.h>
#include <asm/arch/pinmux.h>
#include <asm/arch/uart.h>
#include <spi.h>
#include "board.h"
DECLARE_GLOBAL_DATA_PTR;
@ -114,6 +115,9 @@ int board_init(void)
clock_init();
clock_verify();
#ifdef CONFIG_TEGRA2_SPI
spi_init();
#endif
/* boot param addr */
gd->bd->bi_boot_params = (NV_PA_SDRAM_BASE + 0x100);

1
drivers/spi/Makefile
View file

@ -43,6 +43,7 @@ COBJS-$(CONFIG_OMAP3_SPI) += omap3_spi.o
COBJS-$(CONFIG_SOFT_SPI) += soft_spi.o
COBJS-$(CONFIG_SH_SPI) += sh_spi.o
COBJS-$(CONFIG_FSL_ESPI) += fsl_espi.o
COBJS-$(CONFIG_TEGRA2_SPI) += tegra2_spi.o
COBJS := $(COBJS-y)
SRCS := $(COBJS:.o=.c)

265
drivers/spi/tegra2_spi.c Normal file
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@ -0,0 +1,265 @@
/*
* Copyright (c) 2010-2011 NVIDIA Corporation
* With help from the mpc8xxx SPI driver
* With more help from omap3_spi SPI driver
*
* 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
*/
#include <common.h>
#include <malloc.h>
#include <spi.h>
#include <asm/io.h>
#include <asm/gpio.h>
#include <asm/arch/clk_rst.h>
#include <asm/arch/clock.h>
#include <asm/arch/pinmux.h>
#include <asm/arch/tegra2_spi.h>
struct tegra_spi_slave {
struct spi_slave slave;
struct spi_tegra *regs;
unsigned int freq;
unsigned int mode;
};
static inline struct tegra_spi_slave *to_tegra_spi(struct spi_slave *slave)
{
return container_of(slave, struct tegra_spi_slave, slave);
}
int spi_cs_is_valid(unsigned int bus, unsigned int cs)
{
/* Tegra2 SPI-Flash - only 1 device ('bus/cs') */
if (bus != 0 || cs != 0)
return 0;
else
return 1;
}
struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs,
unsigned int max_hz, unsigned int mode)
{
struct tegra_spi_slave *spi;
if (!spi_cs_is_valid(bus, cs)) {
printf("SPI error: unsupported bus %d / chip select %d\n",
bus, cs);
return NULL;
}
if (max_hz > TEGRA2_SPI_MAX_FREQ) {
printf("SPI error: unsupported frequency %d Hz. Max frequency"
" is %d Hz\n", max_hz, TEGRA2_SPI_MAX_FREQ);
return NULL;
}
spi = malloc(sizeof(struct tegra_spi_slave));
if (!spi) {
printf("SPI error: malloc of SPI structure failed\n");
return NULL;
}
spi->slave.bus = bus;
spi->slave.cs = cs;
spi->freq = max_hz;
spi->regs = (struct spi_tegra *)TEGRA2_SPI_BASE;
spi->mode = mode;
return &spi->slave;
}
void spi_free_slave(struct spi_slave *slave)
{
struct tegra_spi_slave *spi = to_tegra_spi(slave);
free(spi);
}
void spi_init(void)
{
/* do nothing */
}
int spi_claim_bus(struct spi_slave *slave)
{
struct tegra_spi_slave *spi = to_tegra_spi(slave);
struct spi_tegra *regs = spi->regs;
u32 reg;
/* Change SPI clock to correct frequency, PLLP_OUT0 source */
clock_start_periph_pll(PERIPH_ID_SPI1, CLOCK_ID_PERIPH, spi->freq);
/* Clear stale status here */
reg = SPI_STAT_RDY | SPI_STAT_RXF_FLUSH | SPI_STAT_TXF_FLUSH | \
SPI_STAT_RXF_UNR | SPI_STAT_TXF_OVF;
writel(reg, &regs->status);
debug("spi_init: STATUS = %08x\n", readl(&regs->status));
/*
* Use sw-controlled CS, so we can clock in data after ReadID, etc.
*/
reg = (spi->mode & 1) << SPI_CMD_ACTIVE_SDA_SHIFT;
if (spi->mode & 2)
reg |= 1 << SPI_CMD_ACTIVE_SCLK_SHIFT;
clrsetbits_le32(&regs->command, SPI_CMD_ACTIVE_SCLK_MASK |
SPI_CMD_ACTIVE_SDA_MASK, SPI_CMD_CS_SOFT | reg);
debug("spi_init: COMMAND = %08x\n", readl(&regs->command));
/*
* SPI pins on Tegra2 are muxed - change pinmux later due to UART
* issue.
*/
pinmux_set_func(PINGRP_GMD, PMUX_FUNC_SFLASH);
pinmux_tristate_disable(PINGRP_LSPI);
return 0;
}
void spi_release_bus(struct spi_slave *slave)
{
/*
* We can't release UART_DISABLE and set pinmux to UART4 here since
* some code (e,g, spi_flash_probe) uses printf() while the SPI
* bus is held. That is arguably bad, but it has the advantage of
* already being in the source tree.
*/
}
void spi_cs_activate(struct spi_slave *slave)
{
struct tegra_spi_slave *spi = to_tegra_spi(slave);
/* CS is negated on Tegra, so drive a 1 to get a 0 */
setbits_le32(&spi->regs->command, SPI_CMD_CS_VAL);
}
void spi_cs_deactivate(struct spi_slave *slave)
{
struct tegra_spi_slave *spi = to_tegra_spi(slave);
/* CS is negated on Tegra, so drive a 0 to get a 1 */
clrbits_le32(&spi->regs->command, SPI_CMD_CS_VAL);
}
int spi_xfer(struct spi_slave *slave, unsigned int bitlen,
const void *data_out, void *data_in, unsigned long flags)
{
struct tegra_spi_slave *spi = to_tegra_spi(slave);
struct spi_tegra *regs = spi->regs;
u32 reg, tmpdout, tmpdin = 0;
const u8 *dout = data_out;
u8 *din = data_in;
int num_bytes;
int ret;
debug("spi_xfer: slave %u:%u dout %08X din %08X bitlen %u\n",
slave->bus, slave->cs, *(u8 *)dout, *(u8 *)din, bitlen);
if (bitlen % 8)
return -1;
num_bytes = bitlen / 8;
ret = 0;
reg = readl(&regs->status);
writel(reg, &regs->status); /* Clear all SPI events via R/W */
debug("spi_xfer entry: STATUS = %08x\n", reg);
reg = readl(&regs->command);
reg |= SPI_CMD_TXEN | SPI_CMD_RXEN;
writel(reg, &regs->command);
debug("spi_xfer: COMMAND = %08x\n", readl(&regs->command));
if (flags & SPI_XFER_BEGIN)
spi_cs_activate(slave);
/* handle data in 32-bit chunks */
while (num_bytes > 0) {
int bytes;
int is_read = 0;
int tm, i;
tmpdout = 0;
bytes = (num_bytes > 4) ? 4 : num_bytes;
if (dout != NULL) {
for (i = 0; i < bytes; ++i)
tmpdout = (tmpdout << 8) | dout[i];
}
num_bytes -= bytes;
if (dout)
dout += bytes;
clrsetbits_le32(&regs->command, SPI_CMD_BIT_LENGTH_MASK,
bytes * 8 - 1);
writel(tmpdout, &regs->tx_fifo);
setbits_le32(&regs->command, SPI_CMD_GO);
/*
* Wait for SPI transmit FIFO to empty, or to time out.
* The RX FIFO status will be read and cleared last
*/
for (tm = 0, is_read = 0; tm < SPI_TIMEOUT; ++tm) {
u32 status;
status = readl(&regs->status);
/* We can exit when we've had both RX and TX activity */
if (is_read && (status & SPI_STAT_TXF_EMPTY))
break;
if ((status & (SPI_STAT_BSY | SPI_STAT_RDY)) !=
SPI_STAT_RDY)
tm++;
else if (!(status & SPI_STAT_RXF_EMPTY)) {
tmpdin = readl(&regs->rx_fifo);
is_read = 1;
/* swap bytes read in */
if (din != NULL) {
for (i = bytes - 1; i >= 0; --i) {
din[i] = tmpdin & 0xff;
tmpdin >>= 8;
}
din += bytes;
}
}
}
if (tm >= SPI_TIMEOUT)
ret = tm;
/* clear ACK RDY, etc. bits */
writel(readl(&regs->status), &regs->status);
}
if (flags & SPI_XFER_END)
spi_cs_deactivate(slave);
debug("spi_xfer: transfer ended. Value=%08x, status = %08x\n",
tmpdin, readl(&regs->status));
if (ret) {
printf("spi_xfer: timeout during SPI transfer, tm %d\n", ret);
return -1;
}
return 0;
}