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path: root/drivers/spi/spi-fsi.c
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Diffstat (limited to 'drivers/spi/spi-fsi.c')
-rw-r--r--drivers/spi/spi-fsi.c139
1 files changed, 108 insertions, 31 deletions
diff --git a/drivers/spi/spi-fsi.c b/drivers/spi/spi-fsi.c
index 37a3e0f8e752..8a440c7078ef 100644
--- a/drivers/spi/spi-fsi.c
+++ b/drivers/spi/spi-fsi.c
@@ -12,6 +12,7 @@
#define FSI_ENGID_SPI 0x23
#define FSI_MBOX_ROOT_CTRL_8 0x2860
+#define FSI_MBOX_ROOT_CTRL_8_SPI_MUX 0xf0000000
#define FSI2SPI_DATA0 0x00
#define FSI2SPI_DATA1 0x04
@@ -24,11 +25,16 @@
#define SPI_FSI_BASE 0x70000
#define SPI_FSI_INIT_TIMEOUT_MS 1000
-#define SPI_FSI_MAX_TRANSFER_SIZE 2048
+#define SPI_FSI_MAX_XFR_SIZE 2048
+#define SPI_FSI_MAX_XFR_SIZE_RESTRICTED 32
#define SPI_FSI_ERROR 0x0
#define SPI_FSI_COUNTER_CFG 0x1
#define SPI_FSI_COUNTER_CFG_LOOPS(x) (((u64)(x) & 0xffULL) << 32)
+#define SPI_FSI_COUNTER_CFG_N2_RX BIT_ULL(8)
+#define SPI_FSI_COUNTER_CFG_N2_TX BIT_ULL(9)
+#define SPI_FSI_COUNTER_CFG_N2_IMPLICIT BIT_ULL(10)
+#define SPI_FSI_COUNTER_CFG_N2_RELOAD BIT_ULL(11)
#define SPI_FSI_CFG1 0x2
#define SPI_FSI_CLOCK_CFG 0x3
#define SPI_FSI_CLOCK_CFG_MM_ENABLE BIT_ULL(32)
@@ -61,7 +67,7 @@
#define SPI_FSI_STATUS_RDR_OVERRUN BIT_ULL(62)
#define SPI_FSI_STATUS_RDR_FULL BIT_ULL(63)
#define SPI_FSI_STATUS_ANY_ERROR \
- (SPI_FSI_STATUS_ERROR | SPI_FSI_STATUS_TDR_UNDERRUN | \
+ (SPI_FSI_STATUS_ERROR | \
SPI_FSI_STATUS_TDR_OVERRUN | SPI_FSI_STATUS_RDR_UNDERRUN | \
SPI_FSI_STATUS_RDR_OVERRUN)
#define SPI_FSI_PORT_CTRL 0x9
@@ -70,6 +76,8 @@ struct fsi_spi {
struct device *dev; /* SPI controller device */
struct fsi_device *fsi; /* FSI2SPI CFAM engine device */
u32 base;
+ size_t max_xfr_size;
+ bool restricted;
};
struct fsi_spi_sequence {
@@ -77,6 +85,26 @@ struct fsi_spi_sequence {
u64 data;
};
+static int fsi_spi_check_mux(struct fsi_device *fsi, struct device *dev)
+{
+ int rc;
+ u32 root_ctrl_8;
+ __be32 root_ctrl_8_be;
+
+ rc = fsi_slave_read(fsi->slave, FSI_MBOX_ROOT_CTRL_8, &root_ctrl_8_be,
+ sizeof(root_ctrl_8_be));
+ if (rc)
+ return rc;
+
+ root_ctrl_8 = be32_to_cpu(root_ctrl_8_be);
+ dev_dbg(dev, "Root control register 8: %08x\n", root_ctrl_8);
+ if ((root_ctrl_8 & FSI_MBOX_ROOT_CTRL_8_SPI_MUX) ==
+ FSI_MBOX_ROOT_CTRL_8_SPI_MUX)
+ return 0;
+
+ return -ENOLINK;
+}
+
static int fsi_spi_check_status(struct fsi_spi *ctx)
{
int rc;
@@ -205,8 +233,12 @@ static int fsi_spi_reset(struct fsi_spi *ctx)
if (rc)
return rc;
- return fsi_spi_write_reg(ctx, SPI_FSI_CLOCK_CFG,
- SPI_FSI_CLOCK_CFG_RESET2);
+ rc = fsi_spi_write_reg(ctx, SPI_FSI_CLOCK_CFG,
+ SPI_FSI_CLOCK_CFG_RESET2);
+ if (rc)
+ return rc;
+
+ return fsi_spi_write_reg(ctx, SPI_FSI_STATUS, 0ULL);
}
static int fsi_spi_sequence_add(struct fsi_spi_sequence *seq, u8 val)
@@ -214,8 +246,8 @@ static int fsi_spi_sequence_add(struct fsi_spi_sequence *seq, u8 val)
/*
* Add the next byte of instruction to the 8-byte sequence register.
* Then decrement the counter so that the next instruction will go in
- * the right place. Return the number of "slots" left in the sequence
- * register.
+ * the right place. Return the index of the slot we just filled in the
+ * sequence register.
*/
seq->data |= (u64)val << seq->bit;
seq->bit -= 8;
@@ -233,40 +265,71 @@ static int fsi_spi_sequence_transfer(struct fsi_spi *ctx,
struct fsi_spi_sequence *seq,
struct spi_transfer *transfer)
{
+ bool docfg = false;
int loops;
int idx;
int rc;
+ u8 val = 0;
u8 len = min(transfer->len, 8U);
u8 rem = transfer->len % len;
+ u64 cfg = 0ULL;
loops = transfer->len / len;
if (transfer->tx_buf) {
- idx = fsi_spi_sequence_add(seq,
- SPI_FSI_SEQUENCE_SHIFT_OUT(len));
+ val = SPI_FSI_SEQUENCE_SHIFT_OUT(len);
+ idx = fsi_spi_sequence_add(seq, val);
+
if (rem)
rem = SPI_FSI_SEQUENCE_SHIFT_OUT(rem);
} else if (transfer->rx_buf) {
- idx = fsi_spi_sequence_add(seq,
- SPI_FSI_SEQUENCE_SHIFT_IN(len));
+ val = SPI_FSI_SEQUENCE_SHIFT_IN(len);
+ idx = fsi_spi_sequence_add(seq, val);
+
if (rem)
rem = SPI_FSI_SEQUENCE_SHIFT_IN(rem);
} else {
return -EINVAL;
}
+ if (ctx->restricted) {
+ const int eidx = rem ? 5 : 6;
+
+ while (loops > 1 && idx <= eidx) {
+ idx = fsi_spi_sequence_add(seq, val);
+ loops--;
+ docfg = true;
+ }
+
+ if (loops > 1) {
+ dev_warn(ctx->dev, "No sequencer slots; aborting.\n");
+ return -EINVAL;
+ }
+ }
+
if (loops > 1) {
fsi_spi_sequence_add(seq, SPI_FSI_SEQUENCE_BRANCH(idx));
+ docfg = true;
+ }
- if (rem)
- fsi_spi_sequence_add(seq, rem);
+ if (docfg) {
+ cfg = SPI_FSI_COUNTER_CFG_LOOPS(loops - 1);
+ if (transfer->rx_buf)
+ cfg |= SPI_FSI_COUNTER_CFG_N2_RX |
+ SPI_FSI_COUNTER_CFG_N2_TX |
+ SPI_FSI_COUNTER_CFG_N2_IMPLICIT |
+ SPI_FSI_COUNTER_CFG_N2_RELOAD;
- rc = fsi_spi_write_reg(ctx, SPI_FSI_COUNTER_CFG,
- SPI_FSI_COUNTER_CFG_LOOPS(loops - 1));
+ rc = fsi_spi_write_reg(ctx, SPI_FSI_COUNTER_CFG, cfg);
if (rc)
return rc;
+ } else {
+ fsi_spi_write_reg(ctx, SPI_FSI_COUNTER_CFG, 0ULL);
}
+ if (rem)
+ fsi_spi_sequence_add(seq, rem);
+
return 0;
}
@@ -275,6 +338,7 @@ static int fsi_spi_transfer_data(struct fsi_spi *ctx,
{
int rc = 0;
u64 status = 0ULL;
+ u64 cfg = 0ULL;
if (transfer->tx_buf) {
int nb;
@@ -312,6 +376,16 @@ static int fsi_spi_transfer_data(struct fsi_spi *ctx,
u64 in = 0ULL;
u8 *rx = transfer->rx_buf;
+ rc = fsi_spi_read_reg(ctx, SPI_FSI_COUNTER_CFG, &cfg);
+ if (rc)
+ return rc;
+
+ if (cfg & SPI_FSI_COUNTER_CFG_N2_IMPLICIT) {
+ rc = fsi_spi_write_reg(ctx, SPI_FSI_DATA_TX, 0);
+ if (rc)
+ return rc;
+ }
+
while (transfer->len > recv) {
do {
rc = fsi_spi_read_reg(ctx, SPI_FSI_STATUS,
@@ -350,7 +424,7 @@ static int fsi_spi_transfer_init(struct fsi_spi *ctx)
u64 status = 0ULL;
u64 wanted_clock_cfg = SPI_FSI_CLOCK_CFG_ECC_DISABLE |
SPI_FSI_CLOCK_CFG_SCK_NO_DEL |
- FIELD_PREP(SPI_FSI_CLOCK_CFG_SCK_DIV, 4);
+ FIELD_PREP(SPI_FSI_CLOCK_CFG_SCK_DIV, 19);
end = jiffies + msecs_to_jiffies(SPI_FSI_INIT_TIMEOUT_MS);
do {
@@ -396,18 +470,22 @@ static int fsi_spi_transfer_init(struct fsi_spi *ctx)
static int fsi_spi_transfer_one_message(struct spi_controller *ctlr,
struct spi_message *mesg)
{
- int rc = 0;
+ int rc;
u8 seq_slave = SPI_FSI_SEQUENCE_SEL_SLAVE(mesg->spi->chip_select + 1);
struct spi_transfer *transfer;
struct fsi_spi *ctx = spi_controller_get_devdata(ctlr);
+ rc = fsi_spi_check_mux(ctx->fsi, ctx->dev);
+ if (rc)
+ return rc;
+
list_for_each_entry(transfer, &mesg->transfers, transfer_list) {
struct fsi_spi_sequence seq;
struct spi_transfer *next = NULL;
/* Sequencer must do shift out (tx) first. */
if (!transfer->tx_buf ||
- transfer->len > SPI_FSI_MAX_TRANSFER_SIZE) {
+ transfer->len > (ctx->max_xfr_size + 8)) {
rc = -EINVAL;
goto error;
}
@@ -431,7 +509,7 @@ static int fsi_spi_transfer_one_message(struct spi_controller *ctlr,
/* Sequencer can only do shift in (rx) after tx. */
if (next->rx_buf) {
- if (next->len > SPI_FSI_MAX_TRANSFER_SIZE) {
+ if (next->len > ctx->max_xfr_size) {
rc = -EINVAL;
goto error;
}
@@ -476,30 +554,21 @@ error:
static size_t fsi_spi_max_transfer_size(struct spi_device *spi)
{
- return SPI_FSI_MAX_TRANSFER_SIZE;
+ struct fsi_spi *ctx = spi_controller_get_devdata(spi->controller);
+
+ return ctx->max_xfr_size;
}
static int fsi_spi_probe(struct device *dev)
{
int rc;
- u32 root_ctrl_8;
struct device_node *np;
int num_controllers_registered = 0;
struct fsi_device *fsi = to_fsi_dev(dev);
- /*
- * Check the SPI mux before attempting to probe. If the mux isn't set
- * then the SPI controllers can't access their slave devices.
- */
- rc = fsi_slave_read(fsi->slave, FSI_MBOX_ROOT_CTRL_8, &root_ctrl_8,
- sizeof(root_ctrl_8));
+ rc = fsi_spi_check_mux(fsi, dev);
if (rc)
- return rc;
-
- if (!root_ctrl_8) {
- dev_dbg(dev, "SPI mux not set, aborting probe.\n");
return -ENODEV;
- }
for_each_available_child_of_node(dev->of_node, np) {
u32 base;
@@ -524,6 +593,14 @@ static int fsi_spi_probe(struct device *dev)
ctx->fsi = fsi;
ctx->base = base + SPI_FSI_BASE;
+ if (of_device_is_compatible(np, "ibm,fsi2spi-restricted")) {
+ ctx->restricted = true;
+ ctx->max_xfr_size = SPI_FSI_MAX_XFR_SIZE_RESTRICTED;
+ } else {
+ ctx->restricted = false;
+ ctx->max_xfr_size = SPI_FSI_MAX_XFR_SIZE;
+ }
+
rc = devm_spi_register_controller(dev, ctlr);
if (rc)
spi_controller_put(ctlr);
Copyright © 1996 – 2023 Jason A. Donenfeld. All Rights Reverse Engineered.