[RFC PATCH 2/6] spi: bcm-qspi: Implement the spi_mem interface

Boris Brezillon
2018-02-05T23:21:56Z

From: Boris Brezillon <boris.brezillon@free-electrons.com>

The spi_mem interface is meant to replace the ->spi_flash_read() one.
Implement the ->exec_op() method to ease removal of the old interface.

Not that ->spi_flash_read() is now implemented as a wrapper around the
new bcm_qspi_exec_mem_op() function so that we can easily get rid of
it when ->spi_flash_read() is removed.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
---
drivers/spi/spi-bcm-qspi.c | 205 +++++++++++++++++++++++++++------------------
1 file changed, 124 insertions(+), 81 deletions(-)

diff --git a/drivers/spi/spi-bcm-qspi.c b/drivers/spi/spi-bcm-qspi.c
index a172ab299e80..f47a13453ef6 100644
--- a/drivers/spi/spi-bcm-qspi.c
+++ b/drivers/spi/spi-bcm-qspi.c
@@ -215,10 +215,10 @@ struct bcm_qspi {
int bspi_maj_rev;
int bspi_min_rev;
int bspi_enabled;
- struct spi_flash_read_message *bspi_rf_msg;
- u32 bspi_rf_msg_idx;
- u32 bspi_rf_msg_len;
- u32 bspi_rf_msg_status;
+ const struct spi_mem_op *bspi_rf_op;
+ u32 bspi_rf_op_idx;
+ u32 bspi_rf_op_len;
+ u32 bspi_rf_op_status;
struct bcm_xfer_mode xfer_mode;
u32 s3_strap_override_ctrl;
bool bspi_mode;
@@ -313,26 +313,26 @@ static inline void bcm_qspi_bspi_lr_clear(struct bcm_qspi *qspi)

static void bcm_qspi_bspi_lr_data_read(struct bcm_qspi *qspi)
{
- u32 *buf = (u32 *)qspi->bspi_rf_msg->buf;
+ u32 *buf = (u32 *)qspi->bspi_rf_op->data.buf.in;
u32 data = 0;

- dev_dbg(&qspi->pdev->dev, "xfer %p rx %p rxlen %d\n", qspi->bspi_rf_msg,
- qspi->bspi_rf_msg->buf, qspi->bspi_rf_msg_len);
+ dev_dbg(&qspi->pdev->dev, "xfer %p rx %p rxlen %d\n", qspi->bspi_rf_op,
+ qspi->bspi_rf_op->data.buf.in, qspi->bspi_rf_op_len);
while (!bcm_qspi_bspi_lr_is_fifo_empty(qspi)) {
data = bcm_qspi_bspi_lr_read_fifo(qspi);
- if (likely(qspi->bspi_rf_msg_len >= 4) &&
+ if (likely(qspi->bspi_rf_op_len >= 4) &&
IS_ALIGNED((uintptr_t)buf, 4)) {
- buf[qspi->bspi_rf_msg_idx++] = data;
- qspi->bspi_rf_msg_len -= 4;
+ buf[qspi->bspi_rf_op_idx++] = data;
+ qspi->bspi_rf_op_len -= 4;
} else {
/* Read out remaining bytes, make sure*/
- u8 *cbuf = (u8 *)&buf[qspi->bspi_rf_msg_idx];
+ u8 *cbuf = (u8 *)&buf[qspi->bspi_rf_op_idx];

data = cpu_to_le32(data);
- while (qspi->bspi_rf_msg_len) {
+ while (qspi->bspi_rf_op_len) {
*cbuf++ = (u8)data;
data >>= 8;
- qspi->bspi_rf_msg_len--;
+ qspi->bspi_rf_op_len--;
}
}
}
@@ -349,14 +349,12 @@ static void bcm_qspi_bspi_set_xfer_params(struct bcm_qspi *qspi, u8 cmd_byte,
}

static int bcm_qspi_bspi_set_flex_mode(struct bcm_qspi *qspi,
- struct spi_flash_read_message *msg,
- int hp)
+ const struct spi_mem_op *op, int hp)
{
int bpc = 0, bpp = 0;
- u8 command = msg->read_opcode;
- int width = msg->data_nbits ? msg->data_nbits : SPI_NBITS_SINGLE;
- int addrlen = msg->addr_width;
- int addr_nbits = msg->addr_nbits ? msg->addr_nbits : SPI_NBITS_SINGLE;
+ u8 command = op->cmd.opcode;
+ int width = op->cmd.buswidth ? op->cmd.buswidth : SPI_NBITS_SINGLE;
+ int addrlen = op->addr.nbytes * 8;
int flex_mode = 1;

dev_dbg(&qspi->pdev->dev, "set flex mode w %x addrlen %x hp %d\n",
@@ -365,7 +363,7 @@ static int bcm_qspi_bspi_set_flex_mode(struct bcm_qspi *qspi,
if (addrlen == BSPI_ADDRLEN_4BYTES)
bpp = BSPI_BPP_ADDR_SELECT_MASK;

- bpp |= msg->dummy_bytes * (8/addr_nbits);
+ bpp |= (op->dummy.nbytes * 8) / op->dummy.buswidth;

switch (width) {
case SPI_NBITS_SINGLE:
@@ -397,11 +395,10 @@ static int bcm_qspi_bspi_set_flex_mode(struct bcm_qspi *qspi,
}

static int bcm_qspi_bspi_set_override(struct bcm_qspi *qspi,
- struct spi_flash_read_message *msg,
- int hp)
+ const struct spi_mem_op *op, int hp)
{
- int width = msg->data_nbits ? msg->data_nbits : SPI_NBITS_SINGLE;
- int addrlen = msg->addr_width;
+ int width = op->data.buswidth ? op->data.buswidth : SPI_NBITS_SINGLE;
+ int addrlen = op->addr.nbytes;
u32 data = bcm_qspi_read(qspi, BSPI, BSPI_STRAP_OVERRIDE_CTRL);

dev_dbg(&qspi->pdev->dev, "set override mode w %x addrlen %x hp %d\n",
@@ -437,17 +434,17 @@ static int bcm_qspi_bspi_set_override(struct bcm_qspi *qspi,
/* set the override mode */
data |= BSPI_STRAP_OVERRIDE_CTRL_OVERRIDE;
bcm_qspi_write(qspi, BSPI, BSPI_STRAP_OVERRIDE_CTRL, data);
- bcm_qspi_bspi_set_xfer_params(qspi, msg->read_opcode, 0, 0, 0);
+ bcm_qspi_bspi_set_xfer_params(qspi, op->cmd.opcode, 0, 0, 0);

return 0;
}

static int bcm_qspi_bspi_set_mode(struct bcm_qspi *qspi,
- struct spi_flash_read_message *msg, int hp)
+ const struct spi_mem_op *op, int hp)
{
int error = 0;
- int width = msg->data_nbits ? msg->data_nbits : SPI_NBITS_SINGLE;
- int addrlen = msg->addr_width;
+ int width = op->data.buswidth ? op->data.buswidth : SPI_NBITS_SINGLE;
+ int addrlen = op->addr.nbytes;

/* default mode */
qspi->xfer_mode.flex_mode = true;
@@ -460,12 +457,12 @@ static int bcm_qspi_bspi_set_mode(struct bcm_qspi *qspi,
if (val & mask || qspi->s3_strap_override_ctrl & mask) {
qspi->xfer_mode.flex_mode = false;
bcm_qspi_write(qspi, BSPI, BSPI_FLEX_MODE_ENABLE, 0);
- error = bcm_qspi_bspi_set_override(qspi, msg, hp);
+ error = bcm_qspi_bspi_set_override(qspi, op, hp);
}
}

if (qspi->xfer_mode.flex_mode)
- error = bcm_qspi_bspi_set_flex_mode(qspi, msg, hp);
+ error = bcm_qspi_bspi_set_flex_mode(qspi, op, hp);

if (error) {
dev_warn(&qspi->pdev->dev,
@@ -794,19 +791,24 @@ static int write_to_hw(struct bcm_qspi *qspi, struct spi_device *spi)
return slot;
}

-static int bcm_qspi_bspi_flash_read(struct spi_device *spi,
- struct spi_flash_read_message *msg)
+static int bcm_qspi_bspi_exec_mem_op(struct spi_device *spi,
+ const struct spi_mem_op *op)
{
struct bcm_qspi *qspi = spi_master_get_devdata(spi->master);
- u32 addr = 0, len, rdlen, len_words;
- int ret = 0;
+ u32 addr = 0, len, rdlen, len_words, from = 0;
+ int ret = 0, i;
unsigned long timeo = msecs_to_jiffies(100);
struct bcm_qspi_soc_intc *soc_intc = qspi->soc_intc;

if (bcm_qspi_bspi_ver_three(qspi))
- if (msg->addr_width == BSPI_ADDRLEN_4BYTES)
+ if (op->addr.nbytes == BSPI_ADDRLEN_4BYTES)
return -EIO;

+ for (i = 0; i < op->addr.nbytes; i++) {
+ from <<= 8;
+ from |= op->addr.buf[i];
+ }
+
bcm_qspi_chip_select(qspi, spi->chip_select);
bcm_qspi_write(qspi, MSPI, MSPI_WRITE_LOCK, 0);

@@ -815,15 +817,15 @@ static int bcm_qspi_bspi_flash_read(struct spi_device *spi,
* the upper address byte to bspi
*/
if (bcm_qspi_bspi_ver_three(qspi) == false) {
- addr = msg->from & 0xff000000;
+ addr = from & 0xff000000;
bcm_qspi_write(qspi, BSPI,
BSPI_BSPI_FLASH_UPPER_ADDR_BYTE, addr);
}

if (!qspi->xfer_mode.flex_mode)
- addr = msg->from;
+ addr = from;
else
- addr = msg->from & 0x00ffffff;
+ addr = from & 0x00ffffff;

if (bcm_qspi_bspi_ver_three(qspi) == true)
addr = (addr + 0xc00000) & 0xffffff;
@@ -832,8 +834,8 @@ static int bcm_qspi_bspi_flash_read(struct spi_device *spi,
* read into the entire buffer by breaking the reads
* into RAF buffer read lengths
*/
- len = msg->len;
- qspi->bspi_rf_msg_idx = 0;
+ len = op->data.nbytes;
+ qspi->bspi_rf_op_idx = 0;

do {
if (len > BSPI_READ_LENGTH)
@@ -844,9 +846,9 @@ static int bcm_qspi_bspi_flash_read(struct spi_device *spi,
reinit_completion(&qspi->bspi_done);
bcm_qspi_enable_bspi(qspi);
len_words = (rdlen + 3) >> 2;
- qspi->bspi_rf_msg = msg;
- qspi->bspi_rf_msg_status = 0;
- qspi->bspi_rf_msg_len = rdlen;
+ qspi->bspi_rf_op = op;
+ qspi->bspi_rf_op_status = 0;
+ qspi->bspi_rf_op_len = rdlen;
dev_dbg(&qspi->pdev->dev,
"bspi xfr addr 0x%x len 0x%x", addr, rdlen);
bcm_qspi_write(qspi, BSPI, BSPI_RAF_START_ADDR, addr);
@@ -871,7 +873,6 @@ static int bcm_qspi_bspi_flash_read(struct spi_device *spi,
}

/* set msg return length */
- msg->retlen += rdlen;
addr += rdlen;
len -= rdlen;
} while (len);
@@ -906,61 +907,66 @@ static int bcm_qspi_transfer_one(struct spi_master *master,
return 0;
}

-static int bcm_qspi_mspi_flash_read(struct spi_device *spi,
- struct spi_flash_read_message *msg)
+static int bcm_qspi_mspi_exec_mem_op(struct spi_device *spi,
+ const struct spi_mem_op *op)
{
- struct bcm_qspi *qspi = spi_master_get_devdata(spi->master);
+ struct spi_master *master = spi->master;
+ struct bcm_qspi *qspi = spi_master_get_devdata(master);
struct spi_transfer t[2];
- u8 cmd[6];
- int ret;
+ u8 cmd[6] = { };
+ int ret, i;

memset(cmd, 0, sizeof(cmd));
memset(t, 0, sizeof(t));

/* tx */
/* opcode is in cmd[0] */
- cmd[0] = msg->read_opcode;
- cmd[1] = msg->from >> (msg->addr_width * 8 - 8);
- cmd[2] = msg->from >> (msg->addr_width * 8 - 16);
- cmd[3] = msg->from >> (msg->addr_width * 8 - 24);
- cmd[4] = msg->from >> (msg->addr_width * 8 - 32);
+ cmd[0] = op->cmd.opcode;
+ for (i = 0; i < op->addr.nbytes; i++)
+ cmd[1 + i] = op->addr.buf[i];
t[0].tx_buf = cmd;
- t[0].len = msg->addr_width + msg->dummy_bytes + 1;
+ t[0].len = op->addr.nbytes + op->dummy.nbytes + 1;
t[0].bits_per_word = spi->bits_per_word;
- t[0].tx_nbits = msg->opcode_nbits;
+ t[0].tx_nbits = op->cmd.buswidth;
/* lets mspi know that this is not last transfer */
qspi->trans_pos.mspi_last_trans = false;
- ret = bcm_qspi_transfer_one(spi->master, spi, &t[0]);
+ ret = bcm_qspi_transfer_one(master, spi, &t[0]);

/* rx */
qspi->trans_pos.mspi_last_trans = true;
if (!ret) {
/* rx */
- t[1].rx_buf = msg->buf;
- t[1].len = msg->len;
- t[1].rx_nbits = msg->data_nbits;
+ t[1].rx_buf = op->data.buf.in;
+ t[1].len = op->data.nbytes;
+ t[1].rx_nbits = op->data.buswidth;
t[1].bits_per_word = spi->bits_per_word;
- ret = bcm_qspi_transfer_one(spi->master, spi, &t[1]);
+ ret = bcm_qspi_transfer_one(master, spi, &t[1]);
}

- if (!ret)
- msg->retlen = msg->len;
-
return ret;
}

-static int bcm_qspi_flash_read(struct spi_device *spi,
- struct spi_flash_read_message *msg)
+static int bcm_qspi_exec_mem_op(struct spi_device *spi,
+ const struct spi_mem_op *op)
{
struct bcm_qspi *qspi = spi_master_get_devdata(spi->master);
- int ret = 0;
+ int ret = 0, i;
bool mspi_read = false;
- u32 addr, len;
+ u32 addr = 0, len;
u_char *buf;

- buf = msg->buf;
- addr = msg->from;
- len = msg->len;
+ if (!op->data.nbytes || !op->addr.nbytes || op->addr.nbytes > 4 ||
+ op->data.dir != SPI_MEM_DATA_IN)
+ return -ENOTSUPP;
+
+ buf = op->data.buf.in;
+
+ for (i = 0; i < op->addr.nbytes; i++) {
+ addr <<= 8;
+ addr |= op->addr.buf[i];
+ }
+
+ len = op->data.nbytes;

if (bcm_qspi_bspi_ver_three(qspi) == true) {
/*
@@ -982,12 +988,44 @@ static int bcm_qspi_flash_read(struct spi_device *spi,
mspi_read = true;

if (mspi_read)
- return bcm_qspi_mspi_flash_read(spi, msg);
+ return bcm_qspi_mspi_exec_mem_op(spi, op);

- ret = bcm_qspi_bspi_set_mode(qspi, msg, -1);
+ ret = bcm_qspi_bspi_set_mode(qspi, op, -1);

if (!ret)
- ret = bcm_qspi_bspi_flash_read(spi, msg);
+ ret = bcm_qspi_bspi_exec_mem_op(spi, op);
+
+ return ret;
+}
+
+static int bcm_qspi_exec_mem_op_wrapper(struct spi_mem *mem,
+ const struct spi_mem_op *op)
+{
+ return bcm_qspi_exec_mem_op(mem->spi, op);
+}
+
+static int bcm_qspi_flash_read_wrapper(struct spi_device *spi,
+ struct spi_flash_read_message *msg)
+{
+ int i, ret;
+ u8 addrs[4];
+ struct spi_mem_op op = SPI_MEM_OP(SPI_MEM_OP_CMD(msg->read_opcode, 1),
+ SPI_MEM_OP_ADDRS(msg->addr_width,
+ addrs,
+ msg->addr_nbits),
+ SPI_MEM_OP_DUMMY(msg->dummy_bytes,
+ msg->addr_nbits),
+ SPI_MEM_OP_DATA_IN(msg->len,
+ msg->buf,
+ msg->data_nbits));
+
+ for (i = msg->addr_width - 1; i >= 0; i--)
+ addrs[i] = msg->from >> (i * 8);
+
+ msg->retlen = 0;
+ ret = bcm_qspi_exec_mem_op(spi, &op);
+ if (!ret)
+ msg->retlen = msg->len;

return ret;
}
@@ -1026,10 +1064,10 @@ static irqreturn_t bcm_qspi_bspi_lr_l2_isr(int irq, void *dev_id)
struct bcm_qspi_soc_intc *soc_intc = qspi->soc_intc;
u32 status = qspi_dev_id->irqp->mask;

- if (qspi->bspi_enabled && qspi->bspi_rf_msg) {
+ if (qspi->bspi_enabled && qspi->bspi_rf_op) {
bcm_qspi_bspi_lr_data_read(qspi);
- if (qspi->bspi_rf_msg_len == 0) {
- qspi->bspi_rf_msg = NULL;
+ if (qspi->bspi_rf_op_len == 0) {
+ qspi->bspi_rf_op = NULL;
if (qspi->soc_intc) {
/* disable soc BSPI interrupt */
soc_intc->bcm_qspi_int_set(soc_intc, BSPI_DONE,
@@ -1038,7 +1076,7 @@ static irqreturn_t bcm_qspi_bspi_lr_l2_isr(int irq, void *dev_id)
status = INTR_BSPI_LR_SESSION_DONE_MASK;
}

- if (qspi->bspi_rf_msg_status)
+ if (qspi->bspi_rf_op_status)
bcm_qspi_bspi_lr_clear(qspi);
else
bcm_qspi_bspi_flush_prefetch_buffers(qspi);
@@ -1050,7 +1088,7 @@ static irqreturn_t bcm_qspi_bspi_lr_l2_isr(int irq, void *dev_id)
}

status &= INTR_BSPI_LR_SESSION_DONE_MASK;
- if (qspi->bspi_enabled && status && qspi->bspi_rf_msg_len == 0)
+ if (qspi->bspi_enabled && status && qspi->bspi_rf_op_len == 0)
complete(&qspi->bspi_done);

return IRQ_HANDLED;
@@ -1063,7 +1101,7 @@ static irqreturn_t bcm_qspi_bspi_lr_err_l2_isr(int irq, void *dev_id)
struct bcm_qspi_soc_intc *soc_intc = qspi->soc_intc;

dev_err(&qspi->pdev->dev, "BSPI INT error\n");
- qspi->bspi_rf_msg_status = -EIO;
+ qspi->bspi_rf_op_status = -EIO;
if (qspi->soc_intc)
/* clear soc interrupt */
soc_intc->bcm_qspi_int_ack(soc_intc, BSPI_ERR);
@@ -1186,6 +1224,10 @@ static void bcm_qspi_hw_uninit(struct bcm_qspi *qspi)

}

+static const struct spi_controller_mem_ops bcm_qspi_mem_ops = {
+ .exec_op = bcm_qspi_exec_mem_op_wrapper,
+};
+
static const struct of_device_id bcm_qspi_of_match[] = {
{ .compatible = "brcm,spi-bcm-qspi" },
{},
@@ -1228,7 +1270,8 @@ int bcm_qspi_probe(struct platform_device *pdev,
master->mode_bits = SPI_CPHA | SPI_CPOL | SPI_RX_DUAL | SPI_RX_QUAD;
master->setup = bcm_qspi_setup;
master->transfer_one = bcm_qspi_transfer_one;
- master->spi_flash_read = bcm_qspi_flash_read;
+ master->spi_flash_read = bcm_qspi_flash_read_wrapper;
+ master->mem_ops = &bcm_qspi_mem_ops;
master->cleanup = bcm_qspi_cleanup;
master->dev.of_node = dev->of_node;
master->num_chipselect = NUM_CHIPSELECT;
--
2.14.1