lkml.org 
[lkml]   [2021]   [Oct]   [8]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 1/3] spi: bcm-qspi: Add mspi spcr3 32/64-bits xfer mode
Date
From: Kamal Dasu <kdasu@broadcom.com>

Adding 32-bits and 64-bits per transfer modes using the SPCR3
register settings provided in MSPI controller ver >= 1.5

Signed-off-by: Kamal Dasu <kdasu@broadcom.com>
---
drivers/spi/spi-bcm-qspi.c | 172 ++++++++++++++++++++++++++++++++-----
1 file changed, 151 insertions(+), 21 deletions(-)

diff --git a/drivers/spi/spi-bcm-qspi.c b/drivers/spi/spi-bcm-qspi.c
index a78e56f566dd..9a2d12e7650c 100644
--- a/drivers/spi/spi-bcm-qspi.c
+++ b/drivers/spi/spi-bcm-qspi.c
@@ -83,6 +83,9 @@
/* MSPI register offsets */
#define MSPI_SPCR0_LSB 0x000
#define MSPI_SPCR0_MSB 0x004
+#define MSPI_SPCR0_MSB_CPHA BIT(0)
+#define MSPI_SPCR0_MSB_CPOL BIT(1)
+#define MSPI_SPCR0_MSB_BITS_SHIFT 0x2
#define MSPI_SPCR1_LSB 0x008
#define MSPI_SPCR1_MSB 0x00c
#define MSPI_NEWQP 0x010
@@ -102,6 +105,7 @@
#define MSPI_NUM_CDRAM 16
#define MSPI_CDRAM_CONT_BIT BIT(7)
#define MSPI_CDRAM_BITSE_BIT BIT(6)
+#define MSPI_CDRAM_DT_BIT BIT(5)
#define MSPI_CDRAM_PCS 0xf

#define MSPI_SPCR2_SPE BIT(6)
@@ -114,6 +118,12 @@
~(BIT(10) | BIT(11)))
#define MSPI_SPCR3_SYSCLKSEL_108 (MSPI_SPCR3_SYSCLKSEL_MASK & \
BIT(11))
+#define MSPI_SPCR3_TXRXDAM_MASK GENMASK(4, 2)
+#define MSPI_SPCR3_DAM_8BYTE 0
+#define MSPI_SPCR3_DAM_16BYTE (BIT(2) | BIT(4))
+#define MSPI_SPCR3_DAM_32BYTE (BIT(3) | BIT(5))
+#define MSPI_SPCR3_DATA_REG_SZ BIT(8)
+#define MSPI_SPCR3_CPHARX BIT(9)

#define MSPI_MSPI_STATUS_SPIF BIT(0)

@@ -153,6 +163,14 @@
#define TRANS_STATUS_BREAK_DESELECT (TRANS_STATUS_BREAK_EOM | \
TRANS_STATUS_BREAK_CS_CHANGE)

+/*
+ * Used for writing and reading data in the right order
+ * to TXRAM and RXRAM when used as 32-bit registers respectively
+ */
+#define swap4bytes(__val) \
+ ((((__val) >> 24) & 0x000000FF) | (((__val) >> 8) & 0x0000FF00) | \
+ (((__val) << 8) & 0x00FF0000) | (((__val) << 24) & 0xFF000000))
+
struct bcm_qspi_parms {
u32 speed_hz;
u8 mode;
@@ -261,7 +279,7 @@ static inline bool bcm_qspi_has_sysclk_108(struct bcm_qspi *qspi)
static inline int bcm_qspi_spbr_min(struct bcm_qspi *qspi)
{
if (bcm_qspi_has_fastbr(qspi))
- return 1;
+ return (bcm_qspi_has_sysclk_108(qspi) ? 4 : 1);
else
return 8;
}
@@ -570,23 +588,23 @@ static void bcm_qspi_hw_set_parms(struct bcm_qspi *qspi,
{
u32 spcr, spbr = 0;

- if (xp->speed_hz)
- spbr = qspi->base_clk / (2 * xp->speed_hz);
-
- spcr = clamp_val(spbr, bcm_qspi_spbr_min(qspi), QSPI_SPBR_MAX);
- bcm_qspi_write(qspi, MSPI, MSPI_SPCR0_LSB, spcr);
-
if (!qspi->mspi_maj_rev)
/* legacy controller */
spcr = MSPI_MASTER_BIT;
else
spcr = 0;

- /* for 16 bit the data should be zero */
- if (xp->bits_per_word != 16)
- spcr |= xp->bits_per_word << 2;
- spcr |= xp->mode & 3;
+ /*
+ * Bits per transfer. BITS determines the number of data bits
+ * transferred if the command control bit (BITSE of a
+ * CDRAM Register) is equal to 1.
+ * If CDRAM BITSE is equal to 0, 8 data bits are transferred
+ * regardless
+ */
+ if (xp->bits_per_word != 16 && xp->bits_per_word != 64)
+ spcr |= xp->bits_per_word << MSPI_SPCR0_MSB_BITS_SHIFT;

+ spcr |= xp->mode & (MSPI_SPCR0_MSB_CPHA | MSPI_SPCR0_MSB_CPOL);
bcm_qspi_write(qspi, MSPI, MSPI_SPCR0_MSB, spcr);

if (bcm_qspi_has_fastbr(qspi)) {
@@ -599,13 +617,37 @@ static void bcm_qspi_hw_set_parms(struct bcm_qspi *qspi,
/* SYSCLK_108 */
spcr |= MSPI_SPCR3_SYSCLKSEL_108;
qspi->base_clk = MSPI_BASE_FREQ * 4;
- /* Change spbr as we changed sysclk */
- bcm_qspi_write(qspi, MSPI, MSPI_SPCR0_LSB, 4);
}

+ if (xp->bits_per_word > 16) {
+ /* data_reg_size 1 (64bit) */
+ spcr |= MSPI_SPCR3_DATA_REG_SZ;
+ /* TxRx RAM data access mode 2 for 32B and set fastdt */
+ spcr |= MSPI_SPCR3_DAM_32BYTE | MSPI_SPCR3_FASTDT;
+ /*
+ * Set length of delay after transfer
+ * DTL from 0(256) to 1
+ */
+ bcm_qspi_write(qspi, MSPI, MSPI_SPCR1_LSB, 1);
+ } else {
+ /* data_reg_size[8] = 0 */
+ spcr &= ~(MSPI_SPCR3_DATA_REG_SZ);
+
+ /*
+ * TxRx RAM access mode 8B
+ * and disable fastdt
+ */
+ spcr &= ~(MSPI_SPCR3_DAM_32BYTE);
+ }
bcm_qspi_write(qspi, MSPI, MSPI_SPCR3, spcr);
}

+ if (xp->speed_hz)
+ spbr = qspi->base_clk / (2 * xp->speed_hz);
+
+ spbr = clamp_val(spbr, bcm_qspi_spbr_min(qspi), QSPI_SPBR_MAX);
+ bcm_qspi_write(qspi, MSPI, MSPI_SPCR0_LSB, spbr);
+
qspi->last_parms = *xp;
}

@@ -626,7 +668,7 @@ static int bcm_qspi_setup(struct spi_device *spi)
{
struct bcm_qspi_parms *xp;

- if (spi->bits_per_word > 16)
+ if (spi->bits_per_word > 64)
return -EINVAL;

xp = spi_get_ctldata(spi);
@@ -665,8 +707,12 @@ static int update_qspi_trans_byte_count(struct bcm_qspi *qspi,
/* count the last transferred bytes */
if (qt->trans->bits_per_word <= 8)
qt->byte++;
- else
+ else if (qt->trans->bits_per_word <= 16)
qt->byte += 2;
+ else if (qt->trans->bits_per_word <= 32)
+ qt->byte += 4;
+ else if (qt->trans->bits_per_word <= 64)
+ qt->byte += 8;

if (qt->byte >= qt->trans->len) {
/* we're at the end of the spi_transfer */
@@ -709,6 +755,33 @@ static inline u16 read_rxram_slot_u16(struct bcm_qspi *qspi, int slot)
((bcm_qspi_read(qspi, MSPI, msb_offset) & 0xff) << 8);
}

+static inline u32 read_rxram_slot_u32(struct bcm_qspi *qspi, int slot)
+{
+ u32 reg_offset = MSPI_RXRAM;
+ u32 offset = reg_offset + (slot << 3);
+ u32 val;
+
+ val = bcm_qspi_read(qspi, MSPI, offset);
+ val = swap4bytes(val);
+
+ return val;
+}
+
+static inline u64 read_rxram_slot_u64(struct bcm_qspi *qspi, int slot)
+{
+ u32 reg_offset = MSPI_RXRAM;
+ u32 lsb_offset = reg_offset + (slot << 3) + 0x4;
+ u32 msb_offset = reg_offset + (slot << 3);
+ u32 msb, lsb;
+
+ msb = bcm_qspi_read(qspi, MSPI, msb_offset);
+ msb = swap4bytes(msb);
+ lsb = bcm_qspi_read(qspi, MSPI, lsb_offset);
+ lsb = swap4bytes(lsb);
+
+ return ((u64)msb << 32 | lsb);
+}
+
static void read_from_hw(struct bcm_qspi *qspi, int slots)
{
struct qspi_trans tp;
@@ -732,7 +805,7 @@ static void read_from_hw(struct bcm_qspi *qspi, int slots)
buf[tp.byte] = read_rxram_slot_u8(qspi, slot);
dev_dbg(&qspi->pdev->dev, "RD %02x\n",
buf ? buf[tp.byte] : 0x0);
- } else {
+ } else if (tp.trans->bits_per_word <= 16) {
u16 *buf = tp.trans->rx_buf;

if (buf)
@@ -740,6 +813,25 @@ static void read_from_hw(struct bcm_qspi *qspi, int slots)
slot);
dev_dbg(&qspi->pdev->dev, "RD %04x\n",
buf ? buf[tp.byte / 2] : 0x0);
+ } else if (tp.trans->bits_per_word <= 32) {
+ u32 *buf = tp.trans->rx_buf;
+
+ if (buf)
+ buf[tp.byte / 4] = read_rxram_slot_u32(qspi,
+ slot);
+ dev_dbg(&qspi->pdev->dev, "RD %08x\n",
+ buf ? buf[tp.byte / 4] : 0x0);
+
+ } else if (tp.trans->bits_per_word <= 64) {
+ u64 *buf = tp.trans->rx_buf;
+
+ if (buf)
+ buf[tp.byte / 8] = read_rxram_slot_u64(qspi,
+ slot);
+ dev_dbg(&qspi->pdev->dev, "RD %llx\n",
+ buf ? buf[tp.byte / 8] : 0x0);
+
+
}

update_qspi_trans_byte_count(qspi, &tp,
@@ -769,6 +861,28 @@ static inline void write_txram_slot_u16(struct bcm_qspi *qspi, int slot,
bcm_qspi_write(qspi, MSPI, lsb_offset, (val & 0xff));
}

+static inline void write_txram_slot_u32(struct bcm_qspi *qspi, int slot,
+ u32 val)
+{
+ u32 reg_offset = MSPI_TXRAM;
+ u32 msb_offset = reg_offset + (slot << 3);
+
+ bcm_qspi_write(qspi, MSPI, msb_offset, swap4bytes(val));
+}
+
+static inline void write_txram_slot_u64(struct bcm_qspi *qspi, int slot,
+ u64 val)
+{
+ u32 reg_offset = MSPI_TXRAM;
+ u32 msb_offset = reg_offset + (slot << 3);
+ u32 lsb_offset = reg_offset + (slot << 3) + 0x4;
+ u32 msb = upper_32_bits(val);
+ u32 lsb = lower_32_bits(val);
+
+ bcm_qspi_write(qspi, MSPI, msb_offset, swap4bytes(msb));
+ bcm_qspi_write(qspi, MSPI, lsb_offset, swap4bytes(lsb));
+}
+
static inline u32 read_cdram_slot(struct bcm_qspi *qspi, int slot)
{
return bcm_qspi_read(qspi, MSPI, MSPI_CDRAM + (slot << 2));
@@ -792,20 +906,39 @@ static int write_to_hw(struct bcm_qspi *qspi, struct spi_device *spi)

/* Run until end of transfer or reached the max data */
while (!tstatus && slot < MSPI_NUM_CDRAM) {
+ mspi_cdram = MSPI_CDRAM_CONT_BIT;
if (tp.trans->bits_per_word <= 8) {
const u8 *buf = tp.trans->tx_buf;
u8 val = buf ? buf[tp.byte] : 0x00;

write_txram_slot_u8(qspi, slot, val);
dev_dbg(&qspi->pdev->dev, "WR %02x\n", val);
- } else {
+ } else if (tp.trans->bits_per_word <= 16) {
const u16 *buf = tp.trans->tx_buf;
u16 val = buf ? buf[tp.byte / 2] : 0x0000;

write_txram_slot_u16(qspi, slot, val);
dev_dbg(&qspi->pdev->dev, "WR %04x\n", val);
+ } else if (tp.trans->bits_per_word <= 32) {
+ const u32 *buf = tp.trans->tx_buf;
+ u32 val = buf ? buf[tp.byte/4] : 0x0;
+
+ write_txram_slot_u32(qspi, slot, val);
+ dev_dbg(&qspi->pdev->dev, "WR %08x\n", val);
+ } else if (tp.trans->bits_per_word <= 64) {
+ const u64 *buf = tp.trans->tx_buf;
+ u64 val = (buf ? buf[tp.byte/8] : 0x0);
+
+ /* use the length of delay from SPCR1_LSB */
+ if (bcm_qspi_has_fastbr(qspi))
+ mspi_cdram |= MSPI_CDRAM_DT_BIT;
+
+ write_txram_slot_u64(qspi, slot, val);
+ dev_dbg(&qspi->pdev->dev, "WR %llx\n", val);
}
- mspi_cdram = MSPI_CDRAM_CONT_BIT;
+
+ mspi_cdram |= ((tp.trans->bits_per_word <= 8) ? 0 :
+ MSPI_CDRAM_BITSE_BIT);

if (has_bspi(qspi))
mspi_cdram &= ~1;
@@ -813,9 +946,6 @@ static int write_to_hw(struct bcm_qspi *qspi, struct spi_device *spi)
mspi_cdram |= (~(1 << spi->chip_select) &
MSPI_CDRAM_PCS);

- mspi_cdram |= ((tp.trans->bits_per_word <= 8) ? 0 :
- MSPI_CDRAM_BITSE_BIT);
-
write_cdram_slot(qspi, slot, mspi_cdram);

tstatus = update_qspi_trans_byte_count(qspi, &tp,
--
2.17.1
\
 
 \ /
  Last update: 2021-10-08 22:37    [W:0.087 / U:0.928 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site