u-boot/drivers/spi/cadence_qspi.c
Tom Rini 83d290c56f SPDX: Convert all of our single license tags to Linux Kernel style
When U-Boot started using SPDX tags we were among the early adopters and
there weren't a lot of other examples to borrow from.  So we picked the
area of the file that usually had a full license text and replaced it
with an appropriate SPDX-License-Identifier: entry.  Since then, the
Linux Kernel has adopted SPDX tags and they place it as the very first
line in a file (except where shebangs are used, then it's second line)
and with slightly different comment styles than us.

In part due to community overlap, in part due to better tag visibility
and in part for other minor reasons, switch over to that style.

This commit changes all instances where we have a single declared
license in the tag as both the before and after are identical in tag
contents.  There's also a few places where I found we did not have a tag
and have introduced one.

Signed-off-by: Tom Rini <trini@konsulko.com>
2018-05-07 09:34:12 -04:00

354 lines
9.2 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright (C) 2012
* Altera Corporation <www.altera.com>
*/
#include <common.h>
#include <dm.h>
#include <fdtdec.h>
#include <malloc.h>
#include <spi.h>
#include <linux/errno.h>
#include "cadence_qspi.h"
#define CQSPI_STIG_READ 0
#define CQSPI_STIG_WRITE 1
#define CQSPI_INDIRECT_READ 2
#define CQSPI_INDIRECT_WRITE 3
DECLARE_GLOBAL_DATA_PTR;
static int cadence_spi_write_speed(struct udevice *bus, uint hz)
{
struct cadence_spi_platdata *plat = bus->platdata;
struct cadence_spi_priv *priv = dev_get_priv(bus);
cadence_qspi_apb_config_baudrate_div(priv->regbase,
CONFIG_CQSPI_REF_CLK, hz);
/* Reconfigure delay timing if speed is changed. */
cadence_qspi_apb_delay(priv->regbase, CONFIG_CQSPI_REF_CLK, hz,
plat->tshsl_ns, plat->tsd2d_ns,
plat->tchsh_ns, plat->tslch_ns);
return 0;
}
/* Calibration sequence to determine the read data capture delay register */
static int spi_calibration(struct udevice *bus, uint hz)
{
struct cadence_spi_priv *priv = dev_get_priv(bus);
void *base = priv->regbase;
u8 opcode_rdid = 0x9F;
unsigned int idcode = 0, temp = 0;
int err = 0, i, range_lo = -1, range_hi = -1;
/* start with slowest clock (1 MHz) */
cadence_spi_write_speed(bus, 1000000);
/* configure the read data capture delay register to 0 */
cadence_qspi_apb_readdata_capture(base, 1, 0);
/* Enable QSPI */
cadence_qspi_apb_controller_enable(base);
/* read the ID which will be our golden value */
err = cadence_qspi_apb_command_read(base, 1, &opcode_rdid,
3, (u8 *)&idcode);
if (err) {
puts("SF: Calibration failed (read)\n");
return err;
}
/* use back the intended clock and find low range */
cadence_spi_write_speed(bus, hz);
for (i = 0; i < CQSPI_READ_CAPTURE_MAX_DELAY; i++) {
/* Disable QSPI */
cadence_qspi_apb_controller_disable(base);
/* reconfigure the read data capture delay register */
cadence_qspi_apb_readdata_capture(base, 1, i);
/* Enable back QSPI */
cadence_qspi_apb_controller_enable(base);
/* issue a RDID to get the ID value */
err = cadence_qspi_apb_command_read(base, 1, &opcode_rdid,
3, (u8 *)&temp);
if (err) {
puts("SF: Calibration failed (read)\n");
return err;
}
/* search for range lo */
if (range_lo == -1 && temp == idcode) {
range_lo = i;
continue;
}
/* search for range hi */
if (range_lo != -1 && temp != idcode) {
range_hi = i - 1;
break;
}
range_hi = i;
}
if (range_lo == -1) {
puts("SF: Calibration failed (low range)\n");
return err;
}
/* Disable QSPI for subsequent initialization */
cadence_qspi_apb_controller_disable(base);
/* configure the final value for read data capture delay register */
cadence_qspi_apb_readdata_capture(base, 1, (range_hi + range_lo) / 2);
debug("SF: Read data capture delay calibrated to %i (%i - %i)\n",
(range_hi + range_lo) / 2, range_lo, range_hi);
/* just to ensure we do once only when speed or chip select change */
priv->qspi_calibrated_hz = hz;
priv->qspi_calibrated_cs = spi_chip_select(bus);
return 0;
}
static int cadence_spi_set_speed(struct udevice *bus, uint hz)
{
struct cadence_spi_platdata *plat = bus->platdata;
struct cadence_spi_priv *priv = dev_get_priv(bus);
int err;
if (hz > plat->max_hz)
hz = plat->max_hz;
/* Disable QSPI */
cadence_qspi_apb_controller_disable(priv->regbase);
/*
* Calibration required for different current SCLK speed, requested
* SCLK speed or chip select
*/
if (priv->previous_hz != hz ||
priv->qspi_calibrated_hz != hz ||
priv->qspi_calibrated_cs != spi_chip_select(bus)) {
err = spi_calibration(bus, hz);
if (err)
return err;
/* prevent calibration run when same as previous request */
priv->previous_hz = hz;
}
/* Enable QSPI */
cadence_qspi_apb_controller_enable(priv->regbase);
debug("%s: speed=%d\n", __func__, hz);
return 0;
}
static int cadence_spi_probe(struct udevice *bus)
{
struct cadence_spi_platdata *plat = bus->platdata;
struct cadence_spi_priv *priv = dev_get_priv(bus);
priv->regbase = plat->regbase;
priv->ahbbase = plat->ahbbase;
if (!priv->qspi_is_init) {
cadence_qspi_apb_controller_init(plat);
priv->qspi_is_init = 1;
}
return 0;
}
static int cadence_spi_set_mode(struct udevice *bus, uint mode)
{
struct cadence_spi_priv *priv = dev_get_priv(bus);
/* Disable QSPI */
cadence_qspi_apb_controller_disable(priv->regbase);
/* Set SPI mode */
cadence_qspi_apb_set_clk_mode(priv->regbase, mode);
/* Enable QSPI */
cadence_qspi_apb_controller_enable(priv->regbase);
return 0;
}
static int cadence_spi_xfer(struct udevice *dev, unsigned int bitlen,
const void *dout, void *din, unsigned long flags)
{
struct udevice *bus = dev->parent;
struct cadence_spi_platdata *plat = bus->platdata;
struct cadence_spi_priv *priv = dev_get_priv(bus);
struct dm_spi_slave_platdata *dm_plat = dev_get_parent_platdata(dev);
void *base = priv->regbase;
u8 *cmd_buf = priv->cmd_buf;
size_t data_bytes;
int err = 0;
u32 mode = CQSPI_STIG_WRITE;
if (flags & SPI_XFER_BEGIN) {
/* copy command to local buffer */
priv->cmd_len = bitlen / 8;
memcpy(cmd_buf, dout, priv->cmd_len);
}
if (flags == (SPI_XFER_BEGIN | SPI_XFER_END)) {
/* if start and end bit are set, the data bytes is 0. */
data_bytes = 0;
} else {
data_bytes = bitlen / 8;
}
debug("%s: len=%d [bytes]\n", __func__, data_bytes);
/* Set Chip select */
cadence_qspi_apb_chipselect(base, spi_chip_select(dev),
plat->is_decoded_cs);
if ((flags & SPI_XFER_END) || (flags == 0)) {
if (priv->cmd_len == 0) {
printf("QSPI: Error, command is empty.\n");
return -1;
}
if (din && data_bytes) {
/* read */
/* Use STIG if no address. */
if (!CQSPI_IS_ADDR(priv->cmd_len))
mode = CQSPI_STIG_READ;
else
mode = CQSPI_INDIRECT_READ;
} else if (dout && !(flags & SPI_XFER_BEGIN)) {
/* write */
if (!CQSPI_IS_ADDR(priv->cmd_len))
mode = CQSPI_STIG_WRITE;
else
mode = CQSPI_INDIRECT_WRITE;
}
switch (mode) {
case CQSPI_STIG_READ:
err = cadence_qspi_apb_command_read(
base, priv->cmd_len, cmd_buf,
data_bytes, din);
break;
case CQSPI_STIG_WRITE:
err = cadence_qspi_apb_command_write(base,
priv->cmd_len, cmd_buf,
data_bytes, dout);
break;
case CQSPI_INDIRECT_READ:
err = cadence_qspi_apb_indirect_read_setup(plat,
priv->cmd_len, dm_plat->mode, cmd_buf);
if (!err) {
err = cadence_qspi_apb_indirect_read_execute
(plat, data_bytes, din);
}
break;
case CQSPI_INDIRECT_WRITE:
err = cadence_qspi_apb_indirect_write_setup
(plat, priv->cmd_len, cmd_buf);
if (!err) {
err = cadence_qspi_apb_indirect_write_execute
(plat, data_bytes, dout);
}
break;
default:
err = -1;
break;
}
if (flags & SPI_XFER_END) {
/* clear command buffer */
memset(cmd_buf, 0, sizeof(priv->cmd_buf));
priv->cmd_len = 0;
}
}
return err;
}
static int cadence_spi_ofdata_to_platdata(struct udevice *bus)
{
struct cadence_spi_platdata *plat = bus->platdata;
const void *blob = gd->fdt_blob;
int node = dev_of_offset(bus);
int subnode;
u32 data[4];
int ret;
/* 2 base addresses are needed, lets get them from the DT */
ret = fdtdec_get_int_array(blob, node, "reg", data, ARRAY_SIZE(data));
if (ret) {
printf("Error: Can't get base addresses (ret=%d)!\n", ret);
return -ENODEV;
}
plat->regbase = (void *)data[0];
plat->ahbbase = (void *)data[2];
plat->is_decoded_cs = fdtdec_get_bool(blob, node, "cdns,is-decoded-cs");
plat->fifo_depth = fdtdec_get_uint(blob, node, "cdns,fifo-depth", 128);
plat->fifo_width = fdtdec_get_uint(blob, node, "cdns,fifo-width", 4);
plat->trigger_address = fdtdec_get_uint(blob, node,
"cdns,trigger-address", 0);
/* All other paramters are embedded in the child node */
subnode = fdt_first_subnode(blob, node);
if (subnode < 0) {
printf("Error: subnode with SPI flash config missing!\n");
return -ENODEV;
}
/* Use 500 KHz as a suitable default */
plat->max_hz = fdtdec_get_uint(blob, subnode, "spi-max-frequency",
500000);
/* Read other parameters from DT */
plat->page_size = fdtdec_get_uint(blob, subnode, "page-size", 256);
plat->block_size = fdtdec_get_uint(blob, subnode, "block-size", 16);
plat->tshsl_ns = fdtdec_get_uint(blob, subnode, "cdns,tshsl-ns", 200);
plat->tsd2d_ns = fdtdec_get_uint(blob, subnode, "cdns,tsd2d-ns", 255);
plat->tchsh_ns = fdtdec_get_uint(blob, subnode, "cdns,tchsh-ns", 20);
plat->tslch_ns = fdtdec_get_uint(blob, subnode, "cdns,tslch-ns", 20);
debug("%s: regbase=%p ahbbase=%p max-frequency=%d page-size=%d\n",
__func__, plat->regbase, plat->ahbbase, plat->max_hz,
plat->page_size);
return 0;
}
static const struct dm_spi_ops cadence_spi_ops = {
.xfer = cadence_spi_xfer,
.set_speed = cadence_spi_set_speed,
.set_mode = cadence_spi_set_mode,
/*
* cs_info is not needed, since we require all chip selects to be
* in the device tree explicitly
*/
};
static const struct udevice_id cadence_spi_ids[] = {
{ .compatible = "cadence,qspi" },
{ }
};
U_BOOT_DRIVER(cadence_spi) = {
.name = "cadence_spi",
.id = UCLASS_SPI,
.of_match = cadence_spi_ids,
.ops = &cadence_spi_ops,
.ofdata_to_platdata = cadence_spi_ofdata_to_platdata,
.platdata_auto_alloc_size = sizeof(struct cadence_spi_platdata),
.priv_auto_alloc_size = sizeof(struct cadence_spi_priv),
.probe = cadence_spi_probe,
};