u-boot/drivers/spi/iproc_qspi.c
Rayagonda Kokatanur 2ba1bd1e11 driver: spi: add bcm iproc qspi support
IPROC qspi driver supports both BSPI and MSPI modes.

Signed-off-by: Rayagonda Kokatanur <rayagonda.kokatanur@broadcom.com>
Signed-off-by: Bharat Gooty <bharat.gooty@broadcom.com>
Acked-by: Rayagonda Kokatanur <rayagonda.kokatanur@broadcom.com>

Signed-off-by: Roman Bacik <roman.bacik@broadcom.com>
Reviewed-by: Jagan Teki <jagan@amarulasolutions.com>
2022-02-24 13:42:50 +05:30

576 lines
15 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright 2020-2021 Broadcom
*/
#include <common.h>
#include <dm.h>
#include <spi.h>
#include <spi-mem.h>
#include <asm/io.h>
#include <linux/delay.h>
#include <linux/err.h>
#include <linux/iopoll.h>
#include <linux/log2.h>
/* Delay required to change the mode of operation */
#define BUSY_DELAY_US 1
#define BUSY_TIMEOUT_US 200000
#define DWORD_ALIGNED(a) (!(((ulong)(a)) & 3))
/* Chip attributes */
#define QSPI_AXI_CLK 175000000
#define SPBR_MIN 8U
#define SPBR_MAX 255U
#define NUM_CDRAM 16U
#define CDRAM_PCS0 2
#define CDRAM_CONT BIT(7)
#define CDRAM_BITS_EN BIT(6)
#define CDRAM_QUAD_MODE BIT(8)
#define CDRAM_RBIT_INPUT BIT(10)
#define MSPI_SPE BIT(6)
#define MSPI_CONT_AFTER_CMD BIT(7)
#define MSPI_MSTR BIT(7)
/* Register fields */
#define MSPI_SPCR0_MSB_BITS_8 0x00000020
#define BSPI_RAF_CONTROL_START_MASK 0x00000001
#define BSPI_RAF_STATUS_SESSION_BUSY_MASK 0x00000001
#define BSPI_RAF_STATUS_FIFO_EMPTY_MASK 0x00000002
#define BSPI_STRAP_OVERRIDE_DATA_QUAD_SHIFT 3
#define BSPI_STRAP_OVERRIDE_4BYTE_SHIFT 2
#define BSPI_STRAP_OVERRIDE_DATA_DUAL_SHIFT 1
#define BSPI_STRAP_OVERRIDE_SHIFT 0
#define BSPI_BPC_DATA_SHIFT 0
#define BSPI_BPC_MODE_SHIFT 8
#define BSPI_BPC_ADDR_SHIFT 16
#define BSPI_BPC_CMD_SHIFT 24
#define BSPI_BPP_ADDR_SHIFT 16
/* MSPI registers */
#define MSPI_SPCR0_LSB_REG 0x000
#define MSPI_SPCR0_MSB_REG 0x004
#define MSPI_SPCR1_LSB_REG 0x008
#define MSPI_SPCR1_MSB_REG 0x00c
#define MSPI_NEWQP_REG 0x010
#define MSPI_ENDQP_REG 0x014
#define MSPI_SPCR2_REG 0x018
#define MSPI_STATUS_REG 0x020
#define MSPI_CPTQP_REG 0x024
#define MSPI_TX_REG 0x040
#define MSPI_RX_REG 0x0c0
#define MSPI_CDRAM_REG 0x140
#define MSPI_WRITE_LOCK_REG 0x180
#define MSPI_DISABLE_FLUSH_GEN_REG 0x184
/* BSPI registers */
#define BSPI_REVISION_ID_REG 0x000
#define BSPI_SCRATCH_REG 0x004
#define BSPI_MAST_N_BOOT_CTRL_REG 0x008
#define BSPI_BUSY_STATUS_REG 0x00c
#define BSPI_INTR_STATUS_REG 0x010
#define BSPI_B0_STATUS_REG 0x014
#define BSPI_B0_CTRL_REG 0x018
#define BSPI_B1_STATUS_REG 0x01c
#define BSPI_B1_CTRL_REG 0x020
#define BSPI_STRAP_OVERRIDE_CTRL_REG 0x024
#define BSPI_FLEX_MODE_ENABLE_REG 0x028
#define BSPI_BITS_PER_CYCLE_REG 0x02C
#define BSPI_BITS_PER_PHASE_REG 0x030
#define BSPI_CMD_AND_MODE_BYTE_REG 0x034
#define BSPI_FLASH_UPPER_ADDR_BYTE_REG 0x038
#define BSPI_XOR_VALUE_REG 0x03C
#define BSPI_XOR_ENABLE_REG 0x040
#define BSPI_PIO_MODE_ENABLE_REG 0x044
#define BSPI_PIO_IODIR_REG 0x048
#define BSPI_PIO_DATA_REG 0x04C
/* RAF registers */
#define BSPI_RAF_START_ADDRESS_REG 0x00
#define BSPI_RAF_NUM_WORDS_REG 0x04
#define BSPI_RAF_CTRL_REG 0x08
#define BSPI_RAF_FULLNESS_REG 0x0C
#define BSPI_RAF_WATERMARK_REG 0x10
#define BSPI_RAF_STATUS_REG 0x14
#define BSPI_RAF_READ_DATA_REG 0x18
#define BSPI_RAF_WORD_CNT_REG 0x1C
#define BSPI_RAF_CURR_ADDR_REG 0x20
#define XFER_DUAL BIT(30)
#define XFER_QUAD BIT(31)
#define FLUSH_BIT BIT(0)
#define MAST_N_BOOT_BIT BIT(0)
#define WRITE_LOCK_BIT BIT(0)
#define CEIL(m, n) (((m) + (n) - 1) / (n))
#define UPPER_BYTE_MASK 0xFF000000
#define SIZE_16MB 0x001000000
/*
* struct bcmspi_priv - qspi private structure
*
* @bspi_addr: bspi read address
* @bspi_4byte_addr: bspi 4 byte address mode
* @mspi: mspi registers block address
* @bspi: bspi registers block address
* @bspi_raf: bspi raf registers block address
*/
struct bcmspi_priv {
u32 bspi_addr;
bool bspi_4byte_addr;
fdt_addr_t mspi;
fdt_addr_t bspi;
fdt_addr_t bspi_raf;
};
/* BSPI mode */
static void bspi_flush_prefetch_buffers(struct bcmspi_priv *priv)
{
writel(0, priv->bspi + BSPI_B0_CTRL_REG);
writel(0, priv->bspi + BSPI_B1_CTRL_REG);
writel(FLUSH_BIT, priv->bspi + BSPI_B0_CTRL_REG);
writel(FLUSH_BIT, priv->bspi + BSPI_B1_CTRL_REG);
}
static int bspi_enable(struct bcmspi_priv *priv)
{
/* Disable write lock */
writel(0, priv->mspi + MSPI_WRITE_LOCK_REG);
/* Flush prefetch buffers */
bspi_flush_prefetch_buffers(priv);
/* Switch to BSPI */
writel(0, priv->bspi + BSPI_MAST_N_BOOT_CTRL_REG);
return 0;
}
static int bspi_disable(struct bcmspi_priv *priv)
{
int ret;
uint val;
if ((readl(priv->bspi + BSPI_MAST_N_BOOT_CTRL_REG) & 1) == 0) {
ret = readl_poll_timeout(priv->bspi + BSPI_BUSY_STATUS_REG, val, !(val & 1),
BUSY_TIMEOUT_US);
if (ret) {
printf("%s: Failed to disable bspi, device busy\n", __func__);
return ret;
}
/* Switch to MSPI */
writel(MAST_N_BOOT_BIT, priv->bspi + BSPI_MAST_N_BOOT_CTRL_REG);
udelay(BUSY_DELAY_US);
val = readl(priv->bspi + BSPI_MAST_N_BOOT_CTRL_REG);
if (!(val & 1)) {
printf("%s: Failed to enable mspi\n", __func__);
return -EBUSY;
}
}
/* Enable write lock */
writel(WRITE_LOCK_BIT, priv->mspi + MSPI_WRITE_LOCK_REG);
return 0;
}
static int bspi_read_via_raf(struct bcmspi_priv *priv, u8 *rx, uint bytes)
{
u32 status;
uint words;
int aligned;
int ret;
/*
* Flush data from the previous session (unlikely)
* Read outstanding bits in the poll condition to empty FIFO
*/
ret = readl_poll_timeout(priv->bspi_raf + BSPI_RAF_STATUS_REG,
status,
(!readl(priv->bspi_raf + BSPI_RAF_READ_DATA_REG) &&
status & BSPI_RAF_STATUS_FIFO_EMPTY_MASK) &&
!(status & BSPI_RAF_STATUS_SESSION_BUSY_MASK),
BUSY_TIMEOUT_US);
if (ret) {
printf("%s: Failed to flush fifo\n", __func__);
return ret;
}
/* Transfer is in words */
words = CEIL(bytes, 4);
/* Setup hardware */
if (priv->bspi_4byte_addr) {
u32 val = priv->bspi_addr & UPPER_BYTE_MASK;
if (val != readl(priv->bspi + BSPI_FLASH_UPPER_ADDR_BYTE_REG)) {
writel(val, priv->bspi + BSPI_FLASH_UPPER_ADDR_BYTE_REG);
bspi_flush_prefetch_buffers(priv);
}
}
writel(priv->bspi_addr & ~UPPER_BYTE_MASK, priv->bspi_raf + BSPI_RAF_START_ADDRESS_REG);
writel(words, priv->bspi_raf + BSPI_RAF_NUM_WORDS_REG);
writel(0, priv->bspi_raf + BSPI_RAF_WATERMARK_REG);
/* Start reading */
writel(BSPI_RAF_CONTROL_START_MASK, priv->bspi_raf + BSPI_RAF_CTRL_REG);
aligned = DWORD_ALIGNED(rx);
while (bytes) {
status = readl(priv->bspi_raf + BSPI_RAF_STATUS_REG);
if (!(status & BSPI_RAF_STATUS_FIFO_EMPTY_MASK)) {
/* RAF is LE only, convert data to host endianness */
u32 data = le32_to_cpu(readl(priv->bspi_raf + BSPI_RAF_READ_DATA_REG));
/* Check if we can use the whole word */
if (aligned && bytes >= 4) {
*(u32 *)rx = data;
rx += 4;
bytes -= 4;
} else {
uint chunk = min(bytes, 4U);
/* Read out bytes one by one */
while (chunk) {
*rx++ = (u8)data;
data >>= 8;
chunk--;
bytes--;
}
}
continue;
}
if (!(status & BSPI_RAF_STATUS_SESSION_BUSY_MASK)) {
/* FIFO is empty and the session is done */
break;
}
}
return 0;
}
static int bspi_read(struct bcmspi_priv *priv, u8 *rx, uint bytes)
{
int ret;
/* Transfer data */
while (bytes > 0) {
/* Special handing since RAF cannot go across 16MB boundary */
uint trans = bytes;
/* Divide into multiple transfers if it goes across the 16MB boundary */
if (priv->bspi_4byte_addr && (priv->bspi_addr >> 24) !=
((priv->bspi_addr + bytes) >> 24))
trans = SIZE_16MB - (priv->bspi_addr & ~UPPER_BYTE_MASK);
ret = bspi_read_via_raf(priv, rx, trans);
if (ret)
return ret;
priv->bspi_addr += trans;
rx += trans;
bytes -= trans;
}
bspi_flush_prefetch_buffers(priv);
return 0;
}
static void bspi_set_flex_mode(struct bcmspi_priv *priv, const struct spi_mem_op *op)
{
int bpp = (op->dummy.nbytes * 8) / op->dummy.buswidth;
int cmd = op->cmd.opcode;
int bpc = ilog2(op->data.buswidth) << BSPI_BPC_DATA_SHIFT |
ilog2(op->addr.buswidth) << BSPI_BPC_ADDR_SHIFT |
ilog2(op->cmd.buswidth) << BSPI_BPC_CMD_SHIFT;
int so = BIT(BSPI_STRAP_OVERRIDE_SHIFT) |
(op->data.buswidth > 1) << BSPI_STRAP_OVERRIDE_DATA_DUAL_SHIFT |
(op->addr.nbytes > 3) << BSPI_STRAP_OVERRIDE_4BYTE_SHIFT |
(op->data.buswidth > 3) << BSPI_STRAP_OVERRIDE_DATA_QUAD_SHIFT;
/* Disable flex mode first */
writel(0, priv->bspi + BSPI_FLEX_MODE_ENABLE_REG);
/* Configure single, dual or quad mode */
writel(bpc, priv->bspi + BSPI_BITS_PER_CYCLE_REG);
/* Opcode */
writel(cmd, priv->bspi + BSPI_CMD_AND_MODE_BYTE_REG);
/* Count of dummy cycles */
writel(bpp, priv->bspi + BSPI_BITS_PER_PHASE_REG);
/* Enable 4-byte address */
if (priv->bspi_4byte_addr) {
setbits_le32(priv->bspi + BSPI_BITS_PER_PHASE_REG, BIT(BSPI_BPP_ADDR_SHIFT));
} else {
clrbits_le32(priv->bspi + BSPI_BITS_PER_PHASE_REG, BIT(BSPI_BPP_ADDR_SHIFT));
writel(0, priv->bspi + BSPI_FLASH_UPPER_ADDR_BYTE_REG);
}
/* Enable flex mode to take effect */
writel(1, priv->bspi + BSPI_FLEX_MODE_ENABLE_REG);
/* Flush prefetch buffers since 32MB window BSPI could be used */
bspi_flush_prefetch_buffers(priv);
/* Override the strap settings */
writel(so, priv->bspi + BSPI_STRAP_OVERRIDE_CTRL_REG);
}
static int bspi_exec_op(struct spi_slave *slave, const struct spi_mem_op *op)
{
struct udevice *bus = dev_get_parent(slave->dev);
struct bcmspi_priv *priv = dev_get_priv(bus);
int ret = -ENOTSUPP;
/* BSPI read */
if (op->data.dir == SPI_MEM_DATA_IN &&
op->data.nbytes && op->addr.nbytes) {
priv->bspi_4byte_addr = (op->addr.nbytes > 3);
priv->bspi_addr = op->addr.val;
bspi_set_flex_mode(priv, op);
ret = bspi_read(priv, op->data.buf.in, op->data.nbytes);
}
return ret;
}
static const struct spi_controller_mem_ops bspi_mem_ops = {
.exec_op = bspi_exec_op,
};
/* MSPI mode */
static int mspi_exec(struct bcmspi_priv *priv, uint bytes, const u8 *tx, u8 *rx, ulong flags)
{
u32 cdr = CDRAM_PCS0 | CDRAM_CONT;
bool use_16bits = !(bytes & 1);
if (flags & XFER_QUAD) {
cdr |= CDRAM_QUAD_MODE;
if (!tx)
cdr |= CDRAM_RBIT_INPUT;
}
while (bytes) {
uint chunk;
uint queues;
uint i;
uint val;
int ret;
if (use_16bits) {
chunk = min(bytes, NUM_CDRAM * 2);
queues = (chunk + 1) / 2;
bytes -= chunk;
/* Fill CDRAMs */
for (i = 0; i < queues; i++)
writel(cdr | CDRAM_BITS_EN, priv->mspi + MSPI_CDRAM_REG + 4 * i);
/* Fill TXRAMs */
for (i = 0; i < chunk; i++)
writel(tx ? tx[i] : 0xff, priv->mspi + MSPI_TX_REG + 4 * i);
} else {
/* Determine how many bytes to process this time */
chunk = min(bytes, NUM_CDRAM);
queues = chunk;
bytes -= chunk;
/* Fill CDRAMs and TXRAMS */
for (i = 0; i < chunk; i++) {
writel(cdr, priv->mspi + MSPI_CDRAM_REG + 4 * i);
writel(tx ? tx[i] : 0xff, priv->mspi + MSPI_TX_REG + 8 * i);
}
}
/* Setup queue pointers */
writel(0, priv->mspi + MSPI_NEWQP_REG);
writel(queues - 1, priv->mspi + MSPI_ENDQP_REG);
/* Deassert CS if requested and it's the last transfer */
if (bytes == 0 && (flags & SPI_XFER_END))
clrbits_le32(priv->mspi + MSPI_CDRAM_REG + ((queues - 1) << 2), CDRAM_CONT);
/* Kick off */
writel(0, priv->mspi + MSPI_STATUS_REG);
if (bytes == 0 && (flags & SPI_XFER_END))
writel(MSPI_SPE, priv->mspi + MSPI_SPCR2_REG);
else
writel(MSPI_SPE | MSPI_CONT_AFTER_CMD,
priv->mspi + MSPI_SPCR2_REG);
ret = readl_poll_timeout(priv->mspi + MSPI_STATUS_REG, val, (val & 1),
BUSY_TIMEOUT_US);
if (ret) {
printf("%s: Failed to disable bspi, device busy\n", __func__);
return ret;
}
/* Read data out */
if (rx) {
if (use_16bits) {
for (i = 0; i < chunk; i++)
rx[i] = readl(priv->mspi + MSPI_RX_REG + 4 * i) & 0xff;
} else {
for (i = 0; i < chunk; i++)
rx[i] = readl(priv->mspi + MSPI_RX_REG + 8 * i + 4) & 0xff;
}
}
/* Advance pointers */
if (tx)
tx += chunk;
if (rx)
rx += chunk;
}
return 0;
}
static int mspi_xfer(struct udevice *dev, uint bitlen, const void *dout, void *din, ulong flags)
{
struct udevice *bus = dev_get_parent(dev);
struct bcmspi_priv *priv = dev_get_priv(bus);
uint bytes;
int ret = 0;
/* we can only transfer multiples of 8 bits */
if (bitlen % 8)
return -EPROTONOSUPPORT;
bytes = bitlen / 8;
if (flags & SPI_XFER_BEGIN) {
/* Switch to MSPI */
ret = bspi_disable(priv);
if (ret)
return ret;
}
/* MSPI: Transfer */
if (bytes)
ret = mspi_exec(priv, bytes, dout, din, flags);
if (flags & SPI_XFER_END) {
/* Switch back to BSPI */
ret = bspi_enable(priv);
if (ret)
return ret;
}
return ret;
}
/* iProc interface */
static int iproc_qspi_set_speed(struct udevice *bus, uint speed)
{
struct bcmspi_priv *priv = dev_get_priv(bus);
uint spbr;
/* MSPI: SCK configuration */
spbr = (QSPI_AXI_CLK - 1) / (2 * speed) + 1;
writel(max(min(spbr, SPBR_MAX), SPBR_MIN), priv->mspi + MSPI_SPCR0_LSB_REG);
return 0;
}
static int iproc_qspi_set_mode(struct udevice *bus, uint mode)
{
struct bcmspi_priv *priv = dev_get_priv(bus);
/* MSPI: set master bit and mode */
writel(MSPI_MSTR /* Master */ | (mode & 3), priv->mspi + MSPI_SPCR0_MSB_REG);
return 0;
}
static int iproc_qspi_claim_bus(struct udevice *dev)
{
/* Nothing to do */
return 0;
}
static int iproc_qspi_release_bus(struct udevice *dev)
{
struct udevice *bus = dev_get_parent(dev);
struct bcmspi_priv *priv = dev_get_priv(bus);
/* Make sure no operation is in progress */
writel(0, priv->mspi + MSPI_SPCR2_REG);
udelay(BUSY_DELAY_US);
return 0;
}
static int iproc_qspi_of_to_plat(struct udevice *bus)
{
struct bcmspi_priv *priv = dev_get_priv(bus);
priv->bspi = dev_read_addr_name(bus, "bspi");
if (IS_ERR((void *)priv->bspi)) {
printf("%s: Failed to get bspi base address\n", __func__);
return PTR_ERR((void *)priv->bspi);
}
priv->bspi_raf = dev_read_addr_name(bus, "bspi_raf");
if (IS_ERR((void *)priv->bspi_raf)) {
printf("%s: Failed to get bspi_raf base address\n", __func__);
return PTR_ERR((void *)priv->bspi_raf);
}
priv->mspi = dev_read_addr_name(bus, "mspi");
if (IS_ERR((void *)priv->mspi)) {
printf("%s: Failed to get mspi base address\n", __func__);
return PTR_ERR((void *)priv->mspi);
}
return 0;
}
static int iproc_qspi_probe(struct udevice *bus)
{
struct bcmspi_priv *priv = dev_get_priv(bus);
/* configure mspi */
writel(0, priv->mspi + MSPI_SPCR1_LSB_REG);
writel(0, priv->mspi + MSPI_SPCR1_MSB_REG);
writel(0, priv->mspi + MSPI_NEWQP_REG);
writel(0, priv->mspi + MSPI_ENDQP_REG);
writel(0, priv->mspi + MSPI_SPCR2_REG);
/* configure bspi */
bspi_enable(priv);
return 0;
}
static const struct dm_spi_ops iproc_qspi_ops = {
.claim_bus = iproc_qspi_claim_bus,
.release_bus = iproc_qspi_release_bus,
.xfer = mspi_xfer,
.set_speed = iproc_qspi_set_speed,
.set_mode = iproc_qspi_set_mode,
.mem_ops = &bspi_mem_ops,
};
static const struct udevice_id iproc_qspi_ids[] = {
{ .compatible = "brcm,iproc-qspi" },
{ }
};
U_BOOT_DRIVER(iproc_qspi) = {
.name = "iproc_qspi",
.id = UCLASS_SPI,
.of_match = iproc_qspi_ids,
.ops = &iproc_qspi_ops,
.of_to_plat = iproc_qspi_of_to_plat,
.priv_auto = sizeof(struct bcmspi_priv),
.probe = iproc_qspi_probe,
};