Whitebox
/
u-boot
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

SPI: Add SPI Driver for EXYNOS.

Browse Source 
This patch adds SPI driver for EXYNOS.

Signed-off-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Padmavathi Venna <padma.v@samsung.com>
Signed-off-by: Gabe Black <gabeblack@google.com>
Signed-off-by: Rajeshwari Shinde <rajeshwari.s@samsung.com>
Signed-off-by: Hatim Ali <hatim.rv@samsung.com>
Acked-by: Mike Frysinger <vapier@gentoo.org>
Acked-by: Simon Glass <sjg@chromium.org>
Tested-by: jy0922.shim@samsung.com
Signed-off-by: Minkyu Kang <mk7.kang@samsung.com>
master
Rajeshwari Shinde 13 years ago committed by Minkyu Kang
parent 383b5cc58c
commit 1bf43b829e
3 changed files with 446 additions and 0 deletions
Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL
Show Stats Download Patch File Download Diff File
  1. 78
      arch/arm/include/asm/arch-exynos/spi.h
  2. 1
      drivers/spi/Makefile
  3. 367
      drivers/spi/exynos_spi.c

78
arch/arm/include/asm/arch-exynos/spi.h
Unescape View File

@ -0,0 +1,78 @@
/*
* (C) Copyright 2012 SAMSUNG Electronics
* Padmavathi Venna <padma.v@samsung.com>
*
* 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
*/
#ifndef __ASM_ARCH_EXYNOS_COMMON_SPI_H_
#define __ASM_ARCH_EXYNOS_COMMON_SPI_H_
#ifndef __ASSEMBLY__
/* SPI peripheral register map; padded to 64KB */
struct exynos_spi {
unsigned int ch_cfg; /* 0x00 */
unsigned char reserved0[4];
unsigned int mode_cfg; /* 0x08 */
unsigned int cs_reg; /* 0x0c */
unsigned char reserved1[4];
unsigned int spi_sts; /* 0x14 */
unsigned int tx_data; /* 0x18 */
unsigned int rx_data; /* 0x1c */
unsigned int pkt_cnt; /* 0x20 */
unsigned char reserved2[4];
unsigned char reserved3[4];
unsigned int fb_clk; /* 0x2c */
unsigned char padding[0xffd0];
};
#define EXYNOS_SPI_MAX_FREQ 50000000
#define SPI_TIMEOUT_MS 10
/* SPI_CHCFG */
#define SPI_CH_HS_EN (1 << 6)
#define SPI_CH_RST (1 << 5)
#define SPI_SLAVE_MODE (1 << 4)
#define SPI_CH_CPOL_L (1 << 3)
#define SPI_CH_CPHA_B (1 << 2)
#define SPI_RX_CH_ON (1 << 1)
#define SPI_TX_CH_ON (1 << 0)
/* SPI_MODECFG */
#define SPI_MODE_CH_WIDTH_WORD (0x2 << 29)
#define SPI_MODE_BUS_WIDTH_WORD (0x2 << 17)
/* SPI_CSREG */
#define SPI_SLAVE_SIG_INACT (1 << 0)
/* SPI_STS */
#define SPI_ST_TX_DONE (1 << 25)
#define SPI_FIFO_LVL_MASK 0x1ff
#define SPI_TX_LVL_OFFSET 6
#define SPI_RX_LVL_OFFSET 15
/* Feedback Delay */
#define SPI_CLK_BYPASS (0 << 0)
#define SPI_FB_DELAY_90 (1 << 0)
#define SPI_FB_DELAY_180 (2 << 0)
#define SPI_FB_DELAY_270 (3 << 0)
/* Packet Count */
#define SPI_PACKET_CNT_EN (1 << 16)
#endif /* __ASSEMBLY__ */
#endif

1
drivers/spi/Makefile
Unescape View File

@ -34,6 +34,7 @@ COBJS-$(CONFIG_BFIN_SPI) += bfin_spi.o
COBJS-$(CONFIG_CF_SPI) += cf_spi.o COBJS-$(CONFIG_CF_SPI) += cf_spi.o
COBJS-$(CONFIG_CF_QSPI) += cf_qspi.o COBJS-$(CONFIG_CF_QSPI) += cf_qspi.o
COBJS-$(CONFIG_DAVINCI_SPI) += davinci_spi.o COBJS-$(CONFIG_DAVINCI_SPI) += davinci_spi.o
COBJS-$(CONFIG_EXYNOS_SPI) += exynos_spi.o
COBJS-$(CONFIG_KIRKWOOD_SPI) += kirkwood_spi.o COBJS-$(CONFIG_KIRKWOOD_SPI) += kirkwood_spi.o
COBJS-$(CONFIG_MPC52XX_SPI) += mpc52xx_spi.o COBJS-$(CONFIG_MPC52XX_SPI) += mpc52xx_spi.o
COBJS-$(CONFIG_MPC8XXX_SPI) += mpc8xxx_spi.o COBJS-$(CONFIG_MPC8XXX_SPI) += mpc8xxx_spi.o

367
drivers/spi/exynos_spi.c
Unescape View File

@ -0,0 +1,367 @@
/*
* (C) Copyright 2012 SAMSUNG Electronics
* Padmavathi Venna <padma.v@samsung.com>
*
* 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/arch/clk.h>
#include <asm/arch/clock.h>
#include <asm/arch/cpu.h>
#include <asm/arch/gpio.h>
#include <asm/arch/pinmux.h>
#include <asm/arch-exynos/spi.h>
#include <asm/io.h>
/* Information about each SPI controller */
struct spi_bus {
enum periph_id periph_id;
s32 frequency; /* Default clock frequency, -1 for none */
struct exynos_spi *regs;
int inited; /* 1 if this bus is ready for use */
};
/* A list of spi buses that we know about */
static struct spi_bus spi_bus[EXYNOS5_SPI_NUM_CONTROLLERS];
struct exynos_spi_slave {
struct spi_slave slave;
struct exynos_spi *regs;
unsigned int freq; /* Default frequency */
unsigned int mode;
enum periph_id periph_id; /* Peripheral ID for this device */
unsigned int fifo_size;
};
static struct spi_bus *spi_get_bus(unsigned dev_index)
{
if (dev_index < EXYNOS5_SPI_NUM_CONTROLLERS)
return &spi_bus[dev_index];
debug("%s: invalid bus %d", __func__, dev_index);
return NULL;
}
static inline struct exynos_spi_slave *to_exynos_spi(struct spi_slave *slave)
{
return container_of(slave, struct exynos_spi_slave, slave);
}
/**
* Setup the driver private data
*
* @param bus ID of the bus that the slave is attached to
* @param cs ID of the chip select connected to the slave
* @param max_hz Required spi frequency
* @param mode Required spi mode (clk polarity, clk phase and
* master or slave)
* @return new device or NULL
*/
struct spi_slave *spi_setup_slave(unsigned int busnum, unsigned int cs,
unsigned int max_hz, unsigned int mode)
{
struct exynos_spi_slave *spi_slave;
struct spi_bus *bus;
if (!spi_cs_is_valid(busnum, cs)) {
debug("%s: Invalid bus/chip select %d, %d\n", __func__,
busnum, cs);
return NULL;
}
spi_slave = malloc(sizeof(*spi_slave));
if (!spi_slave) {
debug("%s: Could not allocate spi_slave\n", __func__);
return NULL;
}
bus = &spi_bus[busnum];
spi_slave->slave.bus = busnum;
spi_slave->slave.cs = cs;
spi_slave->regs = bus->regs;
spi_slave->mode = mode;
spi_slave->periph_id = bus->periph_id;
if (bus->periph_id == PERIPH_ID_SPI1 ||
bus->periph_id == PERIPH_ID_SPI2)
spi_slave->fifo_size = 64;
else
spi_slave->fifo_size = 256;
spi_slave->freq = bus->frequency;
if (max_hz)
spi_slave->freq = min(max_hz, spi_slave->freq);
return &spi_slave->slave;
}
/**
* Free spi controller
*
* @param slave Pointer to spi_slave to which controller has to
* communicate with
*/
void spi_free_slave(struct spi_slave *slave)
{
struct exynos_spi_slave *spi_slave = to_exynos_spi(slave);
free(spi_slave);
}
/**
* Flush spi tx, rx fifos and reset the SPI controller
*
* @param slave Pointer to spi_slave to which controller has to
* communicate with
*/
static void spi_flush_fifo(struct spi_slave *slave)
{
struct exynos_spi_slave *spi_slave = to_exynos_spi(slave);
struct exynos_spi *regs = spi_slave->regs;
clrsetbits_le32(&regs->ch_cfg, SPI_CH_HS_EN, SPI_CH_RST);
clrbits_le32(&regs->ch_cfg, SPI_CH_RST);
setbits_le32(&regs->ch_cfg, SPI_TX_CH_ON | SPI_RX_CH_ON);
}
/**
* Initialize the spi base registers, set the required clock frequency and
* initialize the gpios
*
* @param slave Pointer to spi_slave to which controller has to
* communicate with
* @return zero on success else a negative value
*/
int spi_claim_bus(struct spi_slave *slave)
{
struct exynos_spi_slave *spi_slave = to_exynos_spi(slave);
struct exynos_spi *regs = spi_slave->regs;
u32 reg = 0;
int ret;
ret = set_spi_clk(spi_slave->periph_id,
spi_slave->freq);
if (ret < 0) {
debug("%s: Failed to setup spi clock\n", __func__);
return ret;
}
exynos_pinmux_config(spi_slave->periph_id, PINMUX_FLAG_NONE);
spi_flush_fifo(slave);
reg = readl(&regs->ch_cfg);
reg &= ~(SPI_CH_CPHA_B | SPI_CH_CPOL_L);
if (spi_slave->mode & SPI_CPHA)
reg |= SPI_CH_CPHA_B;
if (spi_slave->mode & SPI_CPOL)
reg |= SPI_CH_CPOL_L;
writel(reg, &regs->ch_cfg);
writel(SPI_FB_DELAY_180, &regs->fb_clk);
return 0;
}
/**
* Reset the spi H/W and flush the tx and rx fifos
*
* @param slave Pointer to spi_slave to which controller has to
* communicate with
*/
void spi_release_bus(struct spi_slave *slave)
{
spi_flush_fifo(slave);
}
static void spi_get_fifo_levels(struct exynos_spi *regs,
int *rx_lvl, int *tx_lvl)
{
uint32_t spi_sts = readl(&regs->spi_sts);
*rx_lvl = (spi_sts >> SPI_RX_LVL_OFFSET) & SPI_FIFO_LVL_MASK;
*tx_lvl = (spi_sts >> SPI_TX_LVL_OFFSET) & SPI_FIFO_LVL_MASK;
}
/**
* If there's something to transfer, do a software reset and set a
* transaction size.
*
* @param regs SPI peripheral registers
* @param count Number of bytes to transfer
*/
static void spi_request_bytes(struct exynos_spi *regs, int count)
{
assert(count && count < (1 << 16));
setbits_le32(&regs->ch_cfg, SPI_CH_RST);
clrbits_le32(&regs->ch_cfg, SPI_CH_RST);
writel(count | SPI_PACKET_CNT_EN, &regs->pkt_cnt);
}
static void spi_rx_tx(struct exynos_spi_slave *spi_slave, int todo,
void **dinp, void const **doutp)
{
struct exynos_spi *regs = spi_slave->regs;
uchar *rxp = *dinp;
const uchar *txp = *doutp;
int rx_lvl, tx_lvl;
uint out_bytes, in_bytes;
out_bytes = in_bytes = todo;
/*
* If there's something to send, do a software reset and set a
* transaction size.
*/
spi_request_bytes(regs, todo);
/*
* Bytes are transmitted/received in pairs. Wait to receive all the
* data because then transmission will be done as well.
*/
while (in_bytes) {
int temp;
/* Keep the fifos full/empty. */
spi_get_fifo_levels(regs, &rx_lvl, &tx_lvl);
if (tx_lvl < spi_slave->fifo_size && out_bytes) {
temp = txp ? *txp++ : 0xff;
writel(temp, &regs->tx_data);
out_bytes--;
}
if (rx_lvl > 0 && in_bytes) {
temp = readl(&regs->rx_data);
if (rxp)
*rxp++ = temp;
in_bytes--;
}
}
*dinp = rxp;
*doutp = txp;
}
/**
* Transfer and receive data
*
* @param slave Pointer to spi_slave to which controller has to
* communicate with
* @param bitlen No of bits to tranfer or receive
* @param dout Pointer to transfer buffer
* @param din Pointer to receive buffer
* @param flags Flags for transfer begin and end
* @return zero on success else a negative value
*/
int spi_xfer(struct spi_slave *slave, unsigned int bitlen, const void *dout,
void *din, unsigned long flags)
{
struct exynos_spi_slave *spi_slave = to_exynos_spi(slave);
int upto, todo;
int bytelen;
/* spi core configured to do 8 bit transfers */
if (bitlen % 8) {
debug("Non byte aligned SPI transfer.\n");
return -1;
}
/* Start the transaction, if necessary. */
if ((flags & SPI_XFER_BEGIN))
spi_cs_activate(slave);
/* Exynos SPI limits each transfer to 65535 bytes */
bytelen = bitlen / 8;
for (upto = 0; upto < bytelen; upto += todo) {
todo = min(bytelen - upto, (1 << 16) - 1);
spi_rx_tx(spi_slave, todo, &din, &dout);
}
/* Stop the transaction, if necessary. */
if ((flags & SPI_XFER_END))
spi_cs_deactivate(slave);
return 0;
}
/**
* Validates the bus and chip select numbers
*
* @param bus ID of the bus that the slave is attached to
* @param cs ID of the chip select connected to the slave
* @return one on success else zero
*/
int spi_cs_is_valid(unsigned int bus, unsigned int cs)
{
return spi_get_bus(bus) && cs == 0;
}
/**
* Activate the CS by driving it LOW
*
* @param slave Pointer to spi_slave to which controller has to
* communicate with
*/
void spi_cs_activate(struct spi_slave *slave)
{
struct exynos_spi_slave *spi_slave = to_exynos_spi(slave);
clrbits_le32(&spi_slave->regs->cs_reg, SPI_SLAVE_SIG_INACT);
debug("Activate CS, bus %d\n", spi_slave->slave.bus);
}
/**
* Deactivate the CS by driving it HIGH
*
* @param slave Pointer to spi_slave to which controller has to
* communicate with
*/
void spi_cs_deactivate(struct spi_slave *slave)
{
struct exynos_spi_slave *spi_slave = to_exynos_spi(slave);
setbits_le32(&spi_slave->regs->cs_reg, SPI_SLAVE_SIG_INACT);
debug("Deactivate CS, bus %d\n", spi_slave->slave.bus);
}
static inline struct exynos_spi *get_spi_base(int dev_index)
{
if (dev_index < 3)
return (struct exynos_spi *)samsung_get_base_spi() + dev_index;
else
return (struct exynos_spi *)samsung_get_base_spi_isp() +
(dev_index - 3);
}
/* Sadly there is no error return from this function */
void spi_init(void)
{
int i;
struct spi_bus *bus;
for (i = 0; i < EXYNOS5_SPI_NUM_CONTROLLERS; i++) {
bus = &spi_bus[i];
bus->regs = get_spi_base(i);
bus->periph_id = PERIPH_ID_SPI0 + i;
/* Although Exynos5 supports upto 50Mhz speed,
* we are setting it to 10Mhz for safe side
*/
bus->frequency = 10000000;
bus->inited = 1;
}
}
Write Preview
Loading…
Cancel
Save