[PATCH v2 4/9] spi: tegra210-quad: Add support for Tegra210 QSPI controller
From: Sowjanya Komatineni
Date: Fri Dec 11 2020 - 12:03:21 EST
Tegra SoC has a Quad SPI controller starting from Tegra210.
This patch adds support for Tegra210 QSPI controller.
Signed-off-by: Sowjanya Komatineni <skomatineni@xxxxxxxxxx>
---
drivers/spi/Kconfig | 9 +
drivers/spi/Makefile | 1 +
drivers/spi/spi-tegra210-quad.c | 1387 +++++++++++++++++++++++++++++++++++++++
3 files changed, 1397 insertions(+)
create mode 100644 drivers/spi/spi-tegra210-quad.c
diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
index aadaea0..f56f20e 100644
--- a/drivers/spi/Kconfig
+++ b/drivers/spi/Kconfig
@@ -843,6 +843,15 @@ config SPI_MXS
help
SPI driver for Freescale MXS devices.
+config SPI_TEGRA210_QUAD
+ tristate "NVIDIA Tegra QSPI Controller"
+ depends on ARCH_TEGRA || COMPILE_TEST
+ depends on RESET_CONTROLLER
+ help
+ QSPI driver for NVIDIA Tegra QSPI Controller interface. This
+ controller is different from the SPI controller and is available
+ on Tegra SoCs starting from Tegra210.
+
config SPI_TEGRA114
tristate "NVIDIA Tegra114 SPI Controller"
depends on (ARCH_TEGRA && TEGRA20_APB_DMA) || COMPILE_TEST
diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile
index 6fea582..c822c5e 100644
--- a/drivers/spi/Makefile
+++ b/drivers/spi/Makefile
@@ -115,6 +115,7 @@ obj-$(CONFIG_SPI_ST_SSC4) += spi-st-ssc4.o
obj-$(CONFIG_SPI_SUN4I) += spi-sun4i.o
obj-$(CONFIG_SPI_SUN6I) += spi-sun6i.o
obj-$(CONFIG_SPI_SYNQUACER) += spi-synquacer.o
+obj-$(CONFIG_SPI_TEGRA210_QUAD) += spi-tegra210-quad.o
obj-$(CONFIG_SPI_TEGRA114) += spi-tegra114.o
obj-$(CONFIG_SPI_TEGRA20_SFLASH) += spi-tegra20-sflash.o
obj-$(CONFIG_SPI_TEGRA20_SLINK) += spi-tegra20-slink.o
diff --git a/drivers/spi/spi-tegra210-quad.c b/drivers/spi/spi-tegra210-quad.c
new file mode 100644
index 0000000..624f395
--- /dev/null
+++ b/drivers/spi/spi-tegra210-quad.c
@@ -0,0 +1,1387 @@
+// SPDX-License-Identifier: GPL-2.0-only
+//
+// Copyright (C) 2020 NVIDIA CORPORATION.
+
+#include <linux/clk.h>
+#include <linux/completion.h>
+#include <linux/delay.h>
+#include <linux/dmaengine.h>
+#include <linux/dma-mapping.h>
+#include <linux/dmapool.h>
+#include <linux/err.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/iopoll.h>
+#include <linux/kernel.h>
+#include <linux/kthread.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/reset.h>
+#include <linux/spi/spi.h>
+
+#define QSPI_COMMAND1 0x000
+#define QSPI_BIT_LENGTH(x) (((x) & 0x1f) << 0)
+#define QSPI_PACKED BIT(5)
+#define QSPI_INTERFACE_WIDTH_MASK (0x03 << 7)
+#define QSPI_INTERFACE_WIDTH(x) (((x) & 0x03) << 7)
+#define QSPI_INTERFACE_WIDTH_SINGLE QSPI_INTERFACE_WIDTH(0)
+#define QSPI_INTERFACE_WIDTH_DUAL QSPI_INTERFACE_WIDTH(1)
+#define QSPI_INTERFACE_WIDTH_QUAD QSPI_INTERFACE_WIDTH(2)
+#define QSPI_SDR_DDR_SEL BIT(9)
+#define QSPI_TX_EN BIT(11)
+#define QSPI_RX_EN BIT(12)
+#define QSPI_CS_SW_VAL BIT(20)
+#define QSPI_CS_SW_HW BIT(21)
+#define QSPI_CONTROL_MODE_0 (0 << 28)
+#define QSPI_CONTROL_MODE_3 (3 << 28)
+#define QSPI_CONTROL_MODE_MASK (3 << 28)
+#define QSPI_M_S BIT(30)
+#define QSPI_PIO BIT(31)
+
+#define QSPI_COMMAND2 0x004
+#define QSPI_TX_TAP_DELAY(x) (((x) & 0x3f) << 10)
+#define QSPI_RX_TAP_DELAY(x) (((x) & 0xff) << 0)
+
+#define QSPI_CS_TIMING1 0x008
+#define QSPI_SETUP_HOLD(setup, hold) (((setup) << 4) | (hold))
+
+#define QSPI_CS_TIMING2 0x00c
+#define CYCLES_BETWEEN_PACKETS_0(x) (((x) & 0x1f) << 0)
+#define CS_ACTIVE_BETWEEN_PACKETS_0 BIT(5)
+
+#define QSPI_TRANS_STATUS 0x010
+#define QSPI_BLK_CNT(val) (((val) >> 0) & 0xffff)
+#define QSPI_RDY BIT(30)
+
+#define QSPI_FIFO_STATUS 0x014
+#define QSPI_RX_FIFO_EMPTY BIT(0)
+#define QSPI_RX_FIFO_FULL BIT(1)
+#define QSPI_TX_FIFO_EMPTY BIT(2)
+#define QSPI_TX_FIFO_FULL BIT(3)
+#define QSPI_RX_FIFO_UNF BIT(4)
+#define QSPI_RX_FIFO_OVF BIT(5)
+#define QSPI_TX_FIFO_UNF BIT(6)
+#define QSPI_TX_FIFO_OVF BIT(7)
+#define QSPI_ERR BIT(8)
+#define QSPI_TX_FIFO_FLUSH BIT(14)
+#define QSPI_RX_FIFO_FLUSH BIT(15)
+#define QSPI_TX_FIFO_EMPTY_COUNT(val) (((val) >> 16) & 0x7f)
+#define QSPI_RX_FIFO_FULL_COUNT(val) (((val) >> 23) & 0x7f)
+
+#define QSPI_FIFO_ERROR (QSPI_RX_FIFO_UNF | \
+ QSPI_RX_FIFO_OVF | \
+ QSPI_TX_FIFO_UNF | \
+ QSPI_TX_FIFO_OVF)
+#define QSPI_FIFO_EMPTY (QSPI_RX_FIFO_EMPTY | \
+ QSPI_TX_FIFO_EMPTY)
+
+#define QSPI_TX_DATA 0x018
+#define QSPI_RX_DATA 0x01c
+
+#define QSPI_DMA_CTL 0x020
+#define QSPI_TX_TRIG(n) (((n) & 0x3) << 15)
+#define QSPI_TX_TRIG_1 QSPI_TX_TRIG(0)
+#define QSPI_TX_TRIG_4 QSPI_TX_TRIG(1)
+#define QSPI_TX_TRIG_8 QSPI_TX_TRIG(2)
+#define QSPI_TX_TRIG_16 QSPI_TX_TRIG(3)
+
+#define QSPI_RX_TRIG(n) (((n) & 0x3) << 19)
+#define QSPI_RX_TRIG_1 QSPI_RX_TRIG(0)
+#define QSPI_RX_TRIG_4 QSPI_RX_TRIG(1)
+#define QSPI_RX_TRIG_8 QSPI_RX_TRIG(2)
+#define QSPI_RX_TRIG_16 QSPI_RX_TRIG(3)
+
+#define QSPI_DMA_EN BIT(31)
+
+#define QSPI_DMA_BLK 0x024
+#define QSPI_DMA_BLK_SET(x) (((x) & 0xffff) << 0)
+
+#define QSPI_TX_FIFO 0x108
+#define QSPI_RX_FIFO 0x188
+
+#define QSPI_FIFO_DEPTH 64
+
+#define QSPI_INTR_MASK 0x18c
+#define QSPI_INTR_RX_FIFO_UNF_MASK BIT(25)
+#define QSPI_INTR_RX_FIFO_OVF_MASK BIT(26)
+#define QSPI_INTR_TX_FIFO_UNF_MASK BIT(27)
+#define QSPI_INTR_TX_FIFO_OVF_MASK BIT(28)
+#define QSPI_INTR_RDY_MASK BIT(29)
+#define QSPI_INTR_RX_TX_FIFO_ERR (QSPI_INTR_RX_FIFO_UNF_MASK | \
+ QSPI_INTR_RX_FIFO_OVF_MASK | \
+ QSPI_INTR_TX_FIFO_UNF_MASK | \
+ QSPI_INTR_TX_FIFO_OVF_MASK)
+
+#define QSPI_MISC_REG 0x194
+#define QSPI_NUM_DUMMY_CYCLE(x) (((x) & 0xff) << 0)
+
+#define DATA_DIR_TX BIT(0)
+#define DATA_DIR_RX BIT(1)
+
+#define QSPI_DMA_TIMEOUT (msecs_to_jiffies(1000))
+#define DEFAULT_QSPI_DMA_BUF_LEN (64 * 1024)
+
+struct tegra_qspi_client_data {
+ int tx_clk_tap_delay;
+ int rx_clk_tap_delay;
+};
+
+struct tegra_qspi {
+ struct device *dev;
+ struct spi_master *master;
+ /* lock to protect data accessed by irq */
+ spinlock_t lock;
+
+ struct clk *clk;
+ struct reset_control *rst;
+ void __iomem *base;
+ phys_addr_t phys;
+ unsigned int irq;
+
+ u32 cur_speed;
+ unsigned int cur_pos;
+ unsigned int words_per_32bit;
+ unsigned int bytes_per_word;
+ unsigned int curr_dma_words;
+ unsigned int cur_direction;
+
+ unsigned int cur_rx_pos;
+ unsigned int cur_tx_pos;
+
+ unsigned int dma_buf_size;
+ unsigned int max_buf_size;
+ bool is_curr_dma_xfer;
+
+ struct completion rx_dma_complete;
+ struct completion tx_dma_complete;
+
+ u32 tx_status;
+ u32 rx_status;
+ u32 status_reg;
+ bool is_packed;
+ bool use_dma;
+
+ u32 command1_reg;
+ u32 dma_control_reg;
+ u32 def_command1_reg;
+ u32 def_command2_reg;
+ u32 spi_cs_timing1;
+ u32 spi_cs_timing2;
+ u8 dummy_cycles;
+
+ struct completion xfer_completion;
+ struct spi_transfer *curr_xfer;
+
+ struct dma_chan *rx_dma_chan;
+ u32 *rx_dma_buf;
+ dma_addr_t rx_dma_phys;
+ struct dma_async_tx_descriptor *rx_dma_desc;
+
+ struct dma_chan *tx_dma_chan;
+ u32 *tx_dma_buf;
+ dma_addr_t tx_dma_phys;
+ struct dma_async_tx_descriptor *tx_dma_desc;
+};
+
+static inline u32 tegra_qspi_readl(struct tegra_qspi *tqspi, unsigned long offset)
+{
+ return readl(tqspi->base + offset);
+}
+
+static inline void tegra_qspi_writel(struct tegra_qspi *tqspi, u32 value, unsigned long offset)
+{
+ writel(value, tqspi->base + offset);
+
+ /* read back register to make sure that register writes completed */
+ if (offset != QSPI_TX_FIFO)
+ readl(tqspi->base + QSPI_COMMAND1);
+}
+
+static void tegra_qspi_mask_clear_irq(struct tegra_qspi *tqspi)
+{
+ u32 value;
+
+ /* write 1 to clear status register */
+ value = tegra_qspi_readl(tqspi, QSPI_TRANS_STATUS);
+ tegra_qspi_writel(tqspi, value, QSPI_TRANS_STATUS);
+
+ value = tegra_qspi_readl(tqspi, QSPI_INTR_MASK);
+ if (!(value & QSPI_INTR_RDY_MASK)) {
+ value |= (QSPI_INTR_RDY_MASK | QSPI_INTR_RX_TX_FIFO_ERR);
+ tegra_qspi_writel(tqspi, value, QSPI_INTR_MASK);
+ }
+
+ /* clear fifo status error if any */
+ value = tegra_qspi_readl(tqspi, QSPI_FIFO_STATUS);
+ if (value & QSPI_ERR)
+ tegra_qspi_writel(tqspi, QSPI_ERR | QSPI_FIFO_ERROR, QSPI_FIFO_STATUS);
+}
+
+static unsigned int
+tegra_qspi_calculate_curr_xfer_param(struct tegra_qspi *tqspi, struct spi_transfer *t)
+{
+ unsigned int max_word, max_len, total_fifo_words;
+ unsigned int remain_len = t->len - tqspi->cur_pos;
+ unsigned int bits_per_word = t->bits_per_word;
+
+ tqspi->bytes_per_word = DIV_ROUND_UP(bits_per_word, 8);
+
+ /*
+ * Tegra QSPI controller supports packed or unpacked mode transfers.
+ * Packed mode is used for data transfers using 8, 16, or 32 bits per
+ * word with a minimum transfer of 1 word and for all other transfers
+ * unpacked mode will be used.
+ */
+
+ if ((bits_per_word == 8 || bits_per_word == 16 ||
+ bits_per_word == 32) && t->len > 3) {
+ tqspi->is_packed = true;
+ tqspi->words_per_32bit = 32 / bits_per_word;
+ } else {
+ tqspi->is_packed = false;
+ tqspi->words_per_32bit = 1;
+ }
+
+ if (tqspi->is_packed) {
+ max_len = min(remain_len, tqspi->max_buf_size);
+ tqspi->curr_dma_words = max_len / tqspi->bytes_per_word;
+ total_fifo_words = (max_len + 3) / 4;
+ } else {
+ max_word = (remain_len - 1) / tqspi->bytes_per_word + 1;
+ max_word = min(max_word, tqspi->max_buf_size / 4);
+ tqspi->curr_dma_words = max_word;
+ total_fifo_words = max_word;
+ }
+
+ return total_fifo_words;
+}
+
+static unsigned int
+tegra_qspi_fill_tx_fifo_from_client_txbuf(struct tegra_qspi *tqspi, struct spi_transfer *t)
+{
+ unsigned int written_words, fifo_words_left, count;
+ unsigned int len, tx_empty_count, max_n_32bit, i;
+ u8 *tx_buf = (u8 *)t->tx_buf + tqspi->cur_tx_pos;
+ u32 fifo_status;
+
+ fifo_status = tegra_qspi_readl(tqspi, QSPI_FIFO_STATUS);
+ tx_empty_count = QSPI_TX_FIFO_EMPTY_COUNT(fifo_status);
+
+ if (tqspi->is_packed) {
+ fifo_words_left = tx_empty_count * tqspi->words_per_32bit;
+ written_words = min(fifo_words_left, tqspi->curr_dma_words);
+ len = written_words * tqspi->bytes_per_word;
+ max_n_32bit = DIV_ROUND_UP(len, 4);
+ for (count = 0; count < max_n_32bit; count++) {
+ u32 x = 0;
+
+ for (i = 0; (i < 4) && len; i++, len--)
+ x |= (u32)(*tx_buf++) << (i * 8);
+ tegra_qspi_writel(tqspi, x, QSPI_TX_FIFO);
+ }
+
+ tqspi->cur_tx_pos += written_words * tqspi->bytes_per_word;
+ } else {
+ unsigned int write_bytes;
+ u8 bytes_per_word = tqspi->bytes_per_word;
+
+ max_n_32bit = min(tqspi->curr_dma_words, tx_empty_count);
+ written_words = max_n_32bit;
+ len = written_words * tqspi->bytes_per_word;
+ if (len > t->len - tqspi->cur_pos)
+ len = t->len - tqspi->cur_pos;
+ write_bytes = len;
+ for (count = 0; count < max_n_32bit; count++) {
+ u32 x = 0;
+
+ for (i = 0; len && (i < bytes_per_word); i++, len--)
+ x |= (u32)(*tx_buf++) << (i * 8);
+ tegra_qspi_writel(tqspi, x, QSPI_TX_FIFO);
+ }
+
+ tqspi->cur_tx_pos += write_bytes;
+ }
+
+ return written_words;
+}
+
+static unsigned int
+tegra_qspi_read_rx_fifo_to_client_rxbuf(struct tegra_qspi *tqspi, struct spi_transfer *t)
+{
+ u8 *rx_buf = (u8 *)t->rx_buf + tqspi->cur_rx_pos;
+ unsigned int len, rx_full_count, count, i;
+ unsigned int read_words = 0;
+ u32 fifo_status, x;
+
+ fifo_status = tegra_qspi_readl(tqspi, QSPI_FIFO_STATUS);
+ rx_full_count = QSPI_RX_FIFO_FULL_COUNT(fifo_status);
+ if (tqspi->is_packed) {
+ len = tqspi->curr_dma_words * tqspi->bytes_per_word;
+ for (count = 0; count < rx_full_count; count++) {
+ x = tegra_qspi_readl(tqspi, QSPI_RX_FIFO);
+
+ for (i = 0; len && (i < 4); i++, len--)
+ *rx_buf++ = (x >> i * 8) & 0xff;
+ }
+
+ read_words += tqspi->curr_dma_words;
+ tqspi->cur_rx_pos += tqspi->curr_dma_words * tqspi->bytes_per_word;
+ } else {
+ u32 rx_mask = ((u32)1 << t->bits_per_word) - 1;
+ u8 bytes_per_word = tqspi->bytes_per_word;
+ unsigned int read_bytes;
+
+ len = rx_full_count * bytes_per_word;
+ if (len > t->len - tqspi->cur_pos)
+ len = t->len - tqspi->cur_pos;
+ read_bytes = len;
+ for (count = 0; count < rx_full_count; count++) {
+ x = tegra_qspi_readl(tqspi, QSPI_RX_FIFO) & rx_mask;
+
+ for (i = 0; len && (i < bytes_per_word); i++, len--)
+ *rx_buf++ = (x >> (i * 8)) & 0xff;
+ }
+
+ read_words += rx_full_count;
+ tqspi->cur_rx_pos += read_bytes;
+ }
+
+ return read_words;
+}
+
+static void
+tegra_qspi_copy_client_txbuf_to_qspi_txbuf(struct tegra_qspi *tqspi, struct spi_transfer *t)
+{
+ dma_sync_single_for_cpu(tqspi->dev, tqspi->tx_dma_phys,
+ tqspi->dma_buf_size, DMA_TO_DEVICE);
+
+ /*
+ * In packed mode, each word in FIFO may contain multiple packets
+ * based on bits per word. So all bytes in each FIFO word are valid.
+ *
+ * In unpacked mode, each word in FIFO contains single packet and
+ * based on bits per word any remaining bits in FIFO word will be
+ * ignored by the hardware and are invalid bits.
+ */
+ if (tqspi->is_packed) {
+ tqspi->cur_tx_pos += tqspi->curr_dma_words * tqspi->bytes_per_word;
+ } else {
+ u8 *tx_buf = (u8 *)t->tx_buf + tqspi->cur_tx_pos;
+ unsigned int i, count, consume, write_bytes;
+
+ /*
+ * Fill tx_dma_buf to contain single packet in each word based
+ * on bits per word from SPI core tx_buf.
+ */
+ consume = tqspi->curr_dma_words * tqspi->bytes_per_word;
+ if (consume > t->len - tqspi->cur_pos)
+ consume = t->len - tqspi->cur_pos;
+ write_bytes = consume;
+ for (count = 0; count < tqspi->curr_dma_words; count++) {
+ u32 x = 0;
+
+ for (i = 0; consume && (i < tqspi->bytes_per_word); i++, consume--)
+ x |= (u32)(*tx_buf++) << (i * 8);
+ tqspi->tx_dma_buf[count] = x;
+ }
+
+ tqspi->cur_tx_pos += write_bytes;
+ }
+
+ dma_sync_single_for_device(tqspi->dev, tqspi->tx_dma_phys,
+ tqspi->dma_buf_size, DMA_TO_DEVICE);
+}
+
+static void
+tegra_qspi_copy_qspi_rxbuf_to_client_rxbuf(struct tegra_qspi *tqspi, struct spi_transfer *t)
+{
+ dma_sync_single_for_cpu(tqspi->dev, tqspi->rx_dma_phys,
+ tqspi->dma_buf_size, DMA_FROM_DEVICE);
+
+ if (tqspi->is_packed) {
+ tqspi->cur_rx_pos += tqspi->curr_dma_words * tqspi->bytes_per_word;
+ } else {
+ unsigned char *rx_buf = t->rx_buf + tqspi->cur_rx_pos;
+ u32 rx_mask = ((u32)1 << t->bits_per_word) - 1;
+ unsigned int i, count, consume, read_bytes;
+
+ /*
+ * Each FIFO word contains single data packet.
+ * Skip invalid bits in each FIFO word based on bits per word
+ * and align bytes while filling in SPI core rx_buf.
+ */
+ consume = tqspi->curr_dma_words * tqspi->bytes_per_word;
+ if (consume > t->len - tqspi->cur_pos)
+ consume = t->len - tqspi->cur_pos;
+ read_bytes = consume;
+ for (count = 0; count < tqspi->curr_dma_words; count++) {
+ u32 x = tqspi->rx_dma_buf[count] & rx_mask;
+
+ for (i = 0; consume && (i < tqspi->bytes_per_word); i++, consume--)
+ *rx_buf++ = (x >> (i * 8)) & 0xff;
+ }
+
+ tqspi->cur_rx_pos += read_bytes;
+ }
+
+ dma_sync_single_for_device(tqspi->dev, tqspi->rx_dma_phys,
+ tqspi->dma_buf_size, DMA_FROM_DEVICE);
+}
+
+static void tegra_qspi_dma_complete(void *args)
+{
+ struct completion *dma_complete = args;
+
+ complete(dma_complete);
+}
+
+static int tegra_qspi_start_tx_dma(struct tegra_qspi *tqspi, struct spi_transfer *t, int len)
+{
+ dma_addr_t tx_dma_phys;
+
+ reinit_completion(&tqspi->tx_dma_complete);
+
+ if (tqspi->is_packed)
+ tx_dma_phys = t->tx_dma;
+ else
+ tx_dma_phys = tqspi->tx_dma_phys;
+
+ tqspi->tx_dma_desc = dmaengine_prep_slave_single(tqspi->tx_dma_chan, tx_dma_phys,
+ len, DMA_MEM_TO_DEV,
+ DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
+
+ if (!tqspi->tx_dma_desc) {
+ dev_err(tqspi->dev, "Unable to get TX descriptor\n");
+ return -EIO;
+ }
+
+ tqspi->tx_dma_desc->callback = tegra_qspi_dma_complete;
+ tqspi->tx_dma_desc->callback_param = &tqspi->tx_dma_complete;
+ dmaengine_submit(tqspi->tx_dma_desc);
+ dma_async_issue_pending(tqspi->tx_dma_chan);
+
+ return 0;
+}
+
+static int tegra_qspi_start_rx_dma(struct tegra_qspi *tqspi, struct spi_transfer *t, int len)
+{
+ dma_addr_t rx_dma_phys;
+
+ reinit_completion(&tqspi->rx_dma_complete);
+
+ if (tqspi->is_packed)
+ rx_dma_phys = t->rx_dma;
+ else
+ rx_dma_phys = tqspi->rx_dma_phys;
+
+ tqspi->rx_dma_desc = dmaengine_prep_slave_single(tqspi->rx_dma_chan, rx_dma_phys,
+ len, DMA_DEV_TO_MEM,
+ DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
+
+ if (!tqspi->rx_dma_desc) {
+ dev_err(tqspi->dev, "Unable to get RX descriptor\n");
+ return -EIO;
+ }
+
+ tqspi->rx_dma_desc->callback = tegra_qspi_dma_complete;
+ tqspi->rx_dma_desc->callback_param = &tqspi->rx_dma_complete;
+ dmaengine_submit(tqspi->rx_dma_desc);
+ dma_async_issue_pending(tqspi->rx_dma_chan);
+
+ return 0;
+}
+
+static int tegra_qspi_flush_fifos(struct tegra_qspi *tqspi, bool atomic)
+{
+ void __iomem *addr = tqspi->base + QSPI_FIFO_STATUS;
+ u32 val;
+
+ val = tegra_qspi_readl(tqspi, QSPI_FIFO_STATUS);
+ if ((val & QSPI_FIFO_EMPTY) == QSPI_FIFO_EMPTY)
+ return 0;
+
+ val |= QSPI_RX_FIFO_FLUSH | QSPI_TX_FIFO_FLUSH;
+ tegra_qspi_writel(tqspi, val, QSPI_FIFO_STATUS);
+
+ if (!atomic)
+ return readl_relaxed_poll_timeout(addr, val,
+ (val & QSPI_FIFO_EMPTY) == QSPI_FIFO_EMPTY,
+ 1000, 1000000);
+
+ return readl_relaxed_poll_timeout_atomic(addr, val,
+ (val & QSPI_FIFO_EMPTY) == QSPI_FIFO_EMPTY,
+ 1000, 1000000);
+}
+
+static void tegra_qspi_unmask_irq(struct tegra_qspi *tqspi)
+{
+ u32 intr_mask;
+
+ intr_mask = tegra_qspi_readl(tqspi, QSPI_INTR_MASK);
+ intr_mask &= ~(QSPI_INTR_RDY_MASK | QSPI_INTR_RX_TX_FIFO_ERR);
+ tegra_qspi_writel(tqspi, intr_mask, QSPI_INTR_MASK);
+}
+
+static int tegra_qspi_dma_map_xfer(struct tegra_qspi *tqspi, struct spi_transfer *t)
+{
+ u8 *tx_buf = (u8 *)t->tx_buf + tqspi->cur_tx_pos;
+ u8 *rx_buf = (u8 *)t->rx_buf + tqspi->cur_rx_pos;
+ unsigned int len;
+
+ len = DIV_ROUND_UP(tqspi->curr_dma_words * tqspi->bytes_per_word, 4) * 4;
+
+ if (t->tx_buf) {
+ t->tx_dma = dma_map_single(tqspi->dev, (void *)tx_buf, len, DMA_TO_DEVICE);
+ if (dma_mapping_error(tqspi->dev, t->tx_dma))
+ return -ENOMEM;
+ }
+
+ if (t->rx_buf) {
+ t->rx_dma = dma_map_single(tqspi->dev, (void *)rx_buf, len, DMA_FROM_DEVICE);
+ if (dma_mapping_error(tqspi->dev, t->rx_dma)) {
+ dma_unmap_single(tqspi->dev, t->tx_dma, len, DMA_TO_DEVICE);
+ return -ENOMEM;
+ }
+ }
+
+ return 0;
+}
+
+static void tegra_qspi_dma_unmap_xfer(struct tegra_qspi *tqspi, struct spi_transfer *t)
+{
+ unsigned int len;
+
+ len = DIV_ROUND_UP(tqspi->curr_dma_words * tqspi->bytes_per_word, 4) * 4;
+
+ dma_unmap_single(tqspi->dev, t->tx_dma, len, DMA_TO_DEVICE);
+ dma_unmap_single(tqspi->dev, t->rx_dma, len, DMA_FROM_DEVICE);
+}
+
+static int tegra_qspi_start_dma_based_transfer(struct tegra_qspi *tqspi, struct spi_transfer *t)
+{
+ struct dma_slave_config dma_sconfig = { 0 };
+ unsigned int len;
+ u8 dma_burst;
+ int ret = 0;
+ u32 val;
+
+ if (tqspi->is_packed) {
+ ret = tegra_qspi_dma_map_xfer(tqspi, t);
+ if (ret < 0)
+ return ret;
+ }
+
+ val = QSPI_DMA_BLK_SET(tqspi->curr_dma_words - 1);
+ tegra_qspi_writel(tqspi, val, QSPI_DMA_BLK);
+
+ tegra_qspi_unmask_irq(tqspi);
+
+ if (tqspi->is_packed)
+ len = DIV_ROUND_UP(tqspi->curr_dma_words * tqspi->bytes_per_word, 4) * 4;
+ else
+ len = tqspi->curr_dma_words * 4;
+
+ /* set attention level based on length of transfer */
+ val = 0;
+ if (len & 0xf) {
+ val |= QSPI_TX_TRIG_1 | QSPI_RX_TRIG_1;
+ dma_burst = 1;
+ } else if (((len) >> 4) & 0x1) {
+ val |= QSPI_TX_TRIG_4 | QSPI_RX_TRIG_4;
+ dma_burst = 4;
+ } else {
+ val |= QSPI_TX_TRIG_8 | QSPI_RX_TRIG_8;
+ dma_burst = 8;
+ }
+
+ tegra_qspi_writel(tqspi, val, QSPI_DMA_CTL);
+ tqspi->dma_control_reg = val;
+
+ dma_sconfig.device_fc = true;
+ if (tqspi->cur_direction & DATA_DIR_TX) {
+ dma_sconfig.dst_addr = tqspi->phys + QSPI_TX_FIFO;
+ dma_sconfig.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
+ dma_sconfig.dst_maxburst = dma_burst;
+ ret = dmaengine_slave_config(tqspi->tx_dma_chan, &dma_sconfig);
+ if (ret < 0) {
+ dev_err(tqspi->dev, "failed DMA slave config: %d\n", ret);
+ return ret;
+ }
+
+ tegra_qspi_copy_client_txbuf_to_qspi_txbuf(tqspi, t);
+ ret = tegra_qspi_start_tx_dma(tqspi, t, len);
+ if (ret < 0) {
+ dev_err(tqspi->dev, "failed to starting TX DMA: %d\n", ret);
+ return ret;
+ }
+ }
+
+ if (tqspi->cur_direction & DATA_DIR_RX) {
+ dma_sconfig.src_addr = tqspi->phys + QSPI_RX_FIFO;
+ dma_sconfig.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
+ dma_sconfig.src_maxburst = dma_burst;
+ ret = dmaengine_slave_config(tqspi->rx_dma_chan, &dma_sconfig);
+ if (ret < 0) {
+ dev_err(tqspi->dev, "failed DMA slave config: %d\n", ret);
+ return ret;
+ }
+
+ dma_sync_single_for_device(tqspi->dev, tqspi->rx_dma_phys,
+ tqspi->dma_buf_size,
+ DMA_FROM_DEVICE);
+
+ ret = tegra_qspi_start_rx_dma(tqspi, t, len);
+ if (ret < 0) {
+ dev_err(tqspi->dev, "failed to start RX DMA: %d\n", ret);
+ if (tqspi->cur_direction & DATA_DIR_TX)
+ dmaengine_terminate_all(tqspi->tx_dma_chan);
+ return ret;
+ }
+ }
+
+ tegra_qspi_writel(tqspi, tqspi->command1_reg, QSPI_COMMAND1);
+
+ tqspi->is_curr_dma_xfer = true;
+ tqspi->dma_control_reg = val;
+ val |= QSPI_DMA_EN;
+ tegra_qspi_writel(tqspi, val, QSPI_DMA_CTL);
+
+ return ret;
+}
+
+static int tegra_qspi_start_cpu_based_transfer(struct tegra_qspi *qspi, struct spi_transfer *t)
+{
+ u32 val;
+ unsigned int cur_words;
+
+ if (qspi->cur_direction & DATA_DIR_TX)
+ cur_words = tegra_qspi_fill_tx_fifo_from_client_txbuf(qspi, t);
+ else
+ cur_words = qspi->curr_dma_words;
+
+ val = QSPI_DMA_BLK_SET(cur_words - 1);
+ tegra_qspi_writel(qspi, val, QSPI_DMA_BLK);
+
+ tegra_qspi_unmask_irq(qspi);
+
+ qspi->is_curr_dma_xfer = false;
+ val = qspi->command1_reg;
+ val |= QSPI_PIO;
+ tegra_qspi_writel(qspi, val, QSPI_COMMAND1);
+
+ return 0;
+}
+
+static void tegra_qspi_deinit_dma(struct tegra_qspi *tqspi)
+{
+ if (tqspi->tx_dma_buf) {
+ dma_free_coherent(tqspi->dev, tqspi->dma_buf_size,
+ tqspi->tx_dma_buf, tqspi->tx_dma_phys);
+ tqspi->tx_dma_buf = NULL;
+ }
+
+ if (tqspi->tx_dma_chan) {
+ dma_release_channel(tqspi->tx_dma_chan);
+ tqspi->tx_dma_chan = NULL;
+ }
+
+ if (tqspi->rx_dma_buf) {
+ dma_free_coherent(tqspi->dev, tqspi->dma_buf_size,
+ tqspi->rx_dma_buf, tqspi->rx_dma_phys);
+ tqspi->rx_dma_buf = NULL;
+ }
+
+ if (tqspi->rx_dma_chan) {
+ dma_release_channel(tqspi->rx_dma_chan);
+ tqspi->rx_dma_chan = NULL;
+ }
+}
+
+static int tegra_qspi_init_dma(struct tegra_qspi *tqspi)
+{
+ struct dma_chan *dma_chan;
+ dma_addr_t dma_phys;
+ u32 *dma_buf;
+ int err;
+
+ dma_chan = dma_request_chan(tqspi->dev, "rx");
+ if (IS_ERR(dma_chan)) {
+ err = PTR_ERR(dma_chan);
+ goto err_out;
+ }
+
+ tqspi->rx_dma_chan = dma_chan;
+
+ dma_buf = dma_alloc_coherent(tqspi->dev, tqspi->dma_buf_size, &dma_phys, GFP_KERNEL);
+ if (!dma_buf) {
+ err = -ENOMEM;
+ goto err_out;
+ }
+
+ tqspi->rx_dma_buf = dma_buf;
+ tqspi->rx_dma_phys = dma_phys;
+
+ dma_chan = dma_request_chan(tqspi->dev, "tx");
+ if (IS_ERR(dma_chan)) {
+ err = PTR_ERR(dma_chan);
+ goto err_out;
+ }
+
+ tqspi->tx_dma_chan = dma_chan;
+
+ dma_buf = dma_alloc_coherent(tqspi->dev, tqspi->dma_buf_size, &dma_phys, GFP_KERNEL);
+ if (!dma_buf) {
+ err = -ENOMEM;
+ goto err_out;
+ }
+
+ tqspi->tx_dma_buf = dma_buf;
+ tqspi->tx_dma_phys = dma_phys;
+ tqspi->use_dma = true;
+
+ return 0;
+
+err_out:
+ tegra_qspi_deinit_dma(tqspi);
+
+ if (err != -EPROBE_DEFER) {
+ dev_err(tqspi->dev, "cannot use DMA: %d\n", err);
+ dev_err(tqspi->dev, "falling back to PIO\n");
+ return 0;
+ }
+
+ return err;
+}
+
+static u32 tegra_qspi_setup_transfer_one(struct spi_device *spi, struct spi_transfer *t,
+ bool is_first_of_msg)
+{
+ struct tegra_qspi *tqspi = spi_master_get_devdata(spi->master);
+ struct tegra_qspi_client_data *cdata = spi->controller_data;
+ u32 command1, command2, speed = t->speed_hz;
+ u8 bits_per_word = t->bits_per_word;
+ u32 tx_tap = 0, rx_tap = 0;
+ int req_mode;
+
+ if (speed != tqspi->cur_speed) {
+ clk_set_rate(tqspi->clk, speed);
+ tqspi->cur_speed = speed;
+ }
+
+ tqspi->cur_pos = 0;
+ tqspi->cur_rx_pos = 0;
+ tqspi->cur_tx_pos = 0;
+ tqspi->curr_xfer = t;
+
+ if (is_first_of_msg) {
+ tegra_qspi_mask_clear_irq(tqspi);
+
+ command1 = tqspi->def_command1_reg;
+ command1 |= QSPI_BIT_LENGTH(bits_per_word - 1);
+
+ command1 &= ~QSPI_CONTROL_MODE_MASK;
+ req_mode = spi->mode & 0x3;
+ if (req_mode == SPI_MODE_3)
+ command1 |= QSPI_CONTROL_MODE_3;
+ else
+ command1 |= QSPI_CONTROL_MODE_0;
+
+ if (spi->mode & SPI_CS_HIGH)
+ command1 |= QSPI_CS_SW_VAL;
+ else
+ command1 &= ~QSPI_CS_SW_VAL;
+ tegra_qspi_writel(tqspi, command1, QSPI_COMMAND1);
+
+ if (cdata && cdata->tx_clk_tap_delay)
+ tx_tap = cdata->tx_clk_tap_delay;
+
+ if (cdata && cdata->rx_clk_tap_delay)
+ rx_tap = cdata->rx_clk_tap_delay;
+
+ command2 = QSPI_TX_TAP_DELAY(tx_tap) | QSPI_RX_TAP_DELAY(rx_tap);
+ if (command2 != tqspi->def_command2_reg)
+ tegra_qspi_writel(tqspi, command2, QSPI_COMMAND2);
+
+ } else {
+ command1 = tqspi->command1_reg;
+ command1 &= ~QSPI_BIT_LENGTH(~0);
+ command1 |= QSPI_BIT_LENGTH(bits_per_word - 1);
+ }
+
+ command1 &= ~QSPI_SDR_DDR_SEL;
+
+ return command1;
+}
+
+static int tegra_qspi_start_transfer_one(struct spi_device *spi,
+ struct spi_transfer *t, u32 command1)
+{
+ struct tegra_qspi *tqspi = spi_master_get_devdata(spi->master);
+ unsigned int total_fifo_words;
+ u8 bus_width = 0;
+ int ret;
+
+ total_fifo_words = tegra_qspi_calculate_curr_xfer_param(tqspi, t);
+
+ command1 &= ~QSPI_PACKED;
+ if (tqspi->is_packed)
+ command1 |= QSPI_PACKED;
+ tegra_qspi_writel(tqspi, command1, QSPI_COMMAND1);
+
+ tqspi->cur_direction = 0;
+
+ command1 &= ~(QSPI_TX_EN | QSPI_RX_EN);
+ if (t->rx_buf) {
+ command1 |= QSPI_RX_EN;
+ tqspi->cur_direction |= DATA_DIR_RX;
+ bus_width = t->rx_nbits;
+ }
+
+ if (t->tx_buf) {
+ command1 |= QSPI_TX_EN;
+ tqspi->cur_direction |= DATA_DIR_TX;
+ bus_width = t->tx_nbits;
+ }
+
+ command1 &= ~QSPI_INTERFACE_WIDTH_MASK;
+
+ if (bus_width == SPI_NBITS_QUAD)
+ command1 |= QSPI_INTERFACE_WIDTH_QUAD;
+ else if (bus_width == SPI_NBITS_DUAL)
+ command1 |= QSPI_INTERFACE_WIDTH_DUAL;
+ else
+ command1 |= QSPI_INTERFACE_WIDTH_SINGLE;
+
+ tqspi->command1_reg = command1;
+
+ ret = tegra_qspi_flush_fifos(tqspi, false);
+ if (ret < 0)
+ return ret;
+
+ if (tqspi->use_dma && total_fifo_words > QSPI_FIFO_DEPTH)
+ ret = tegra_qspi_start_dma_based_transfer(tqspi, t);
+ else
+ ret = tegra_qspi_start_cpu_based_transfer(tqspi, t);
+
+ return ret;
+}
+
+static struct tegra_qspi_client_data *tegra_qspi_parse_cdata_dt(struct spi_device *spi)
+{
+ struct tegra_qspi_client_data *cdata;
+ struct device_node *slave_np = spi->dev.of_node;
+
+ cdata = kzalloc(sizeof(*cdata), GFP_KERNEL);
+ if (!cdata)
+ return NULL;
+
+ of_property_read_u32(slave_np, "nvidia,tx-clk-tap-delay",
+ &cdata->tx_clk_tap_delay);
+ of_property_read_u32(slave_np, "nvidia,rx-clk-tap-delay",
+ &cdata->rx_clk_tap_delay);
+ return cdata;
+}
+
+static void tegra_qspi_cleanup(struct spi_device *spi)
+{
+ struct tegra_qspi_client_data *cdata = spi->controller_data;
+
+ spi->controller_data = NULL;
+ kfree(cdata);
+}
+
+static int tegra_qspi_setup(struct spi_device *spi)
+{
+ struct tegra_qspi *tqspi = spi_master_get_devdata(spi->master);
+ struct tegra_qspi_client_data *cdata = spi->controller_data;
+ unsigned long flags;
+ u32 val;
+ int ret;
+
+ ret = pm_runtime_resume_and_get(tqspi->dev);
+ if (ret < 0) {
+ dev_err(tqspi->dev, "failed to get runtime PM: %d\n", ret);
+ return ret;
+ }
+
+ if (!cdata) {
+ cdata = tegra_qspi_parse_cdata_dt(spi);
+ spi->controller_data = cdata;
+ }
+
+ spin_lock_irqsave(&tqspi->lock, flags);
+
+ /* keep default cs state to inactive */
+ val = tqspi->def_command1_reg;
+ if (spi->mode & SPI_CS_HIGH)
+ val &= ~QSPI_CS_SW_VAL;
+ else
+ val |= QSPI_CS_SW_VAL;
+
+ tqspi->def_command1_reg = val;
+ tegra_qspi_writel(tqspi, tqspi->def_command1_reg, QSPI_COMMAND1);
+
+ spin_unlock_irqrestore(&tqspi->lock, flags);
+
+ pm_runtime_put(tqspi->dev);
+
+ return 0;
+}
+
+static void tegra_qspi_dump_regs(struct tegra_qspi *tqspi)
+{
+ dev_dbg(tqspi->dev, "============ QSPI REGISTER DUMP ============\n");
+ dev_dbg(tqspi->dev, "Command1: 0x%08x | Command2: 0x%08x\n",
+ tegra_qspi_readl(tqspi, QSPI_COMMAND1),
+ tegra_qspi_readl(tqspi, QSPI_COMMAND2));
+ dev_dbg(tqspi->dev, "DMA_CTL: 0x%08x | DMA_BLK: 0x%08x\n",
+ tegra_qspi_readl(tqspi, QSPI_DMA_CTL),
+ tegra_qspi_readl(tqspi, QSPI_DMA_BLK));
+ dev_dbg(tqspi->dev, "INTR_MASK: 0x%08x | MISC: 0x%08x\n",
+ tegra_qspi_readl(tqspi, QSPI_INTR_MASK),
+ tegra_qspi_readl(tqspi, QSPI_MISC_REG));
+ dev_dbg(tqspi->dev, "TRANS_STAT: 0x%08x | FIFO_STATUS: 0x%08x\n",
+ tegra_qspi_readl(tqspi, QSPI_TRANS_STATUS),
+ tegra_qspi_readl(tqspi, QSPI_FIFO_STATUS));
+}
+
+static void tegra_qspi_handle_error(struct tegra_qspi *tqspi)
+{
+ dev_err(tqspi->dev, "error in transfer, fifo status 0x%08x\n", tqspi->status_reg);
+ tegra_qspi_dump_regs(tqspi);
+ tegra_qspi_flush_fifos(tqspi, true);
+ reset_control_assert(tqspi->rst);
+ udelay(2);
+ reset_control_deassert(tqspi->rst);
+}
+
+static void tegra_qspi_transfer_end(struct spi_device *spi)
+{
+ struct tegra_qspi *tqspi = spi_master_get_devdata(spi->master);
+ int cs_val = (spi->mode & SPI_CS_HIGH) ? 0 : 1;
+
+ if (cs_val)
+ tqspi->command1_reg |= QSPI_CS_SW_VAL;
+ else
+ tqspi->command1_reg &= ~QSPI_CS_SW_VAL;
+ tegra_qspi_writel(tqspi, tqspi->command1_reg, QSPI_COMMAND1);
+ tegra_qspi_writel(tqspi, tqspi->def_command1_reg, QSPI_COMMAND1);
+}
+
+static int tegra_qspi_transfer_one_message(struct spi_master *master, struct spi_message *msg)
+{
+ struct tegra_qspi *tqspi = spi_master_get_devdata(master);
+ struct spi_device *spi = msg->spi;
+ struct spi_transfer *xfer;
+ bool is_first_msg = true;
+ int ret;
+
+ msg->status = 0;
+ msg->actual_length = 0;
+ tqspi->tx_status = 0;
+ tqspi->rx_status = 0;
+
+ list_for_each_entry(xfer, &msg->transfers, transfer_list) {
+ u32 cmd1;
+
+ reinit_completion(&tqspi->xfer_completion);
+
+ cmd1 = tegra_qspi_setup_transfer_one(spi, xfer, is_first_msg);
+
+ ret = tegra_qspi_start_transfer_one(spi, xfer, cmd1);
+ if (ret < 0) {
+ dev_err(tqspi->dev, "failed to start transfer: %d\n", ret);
+ goto complete_xfer;
+ }
+
+ is_first_msg = false;
+ ret = wait_for_completion_timeout(&tqspi->xfer_completion,
+ QSPI_DMA_TIMEOUT);
+ if (WARN_ON(ret == 0)) {
+ dev_err(tqspi->dev, "transfer timeout: %d\n", ret);
+ if (tqspi->is_curr_dma_xfer && (tqspi->cur_direction & DATA_DIR_TX))
+ dmaengine_terminate_all(tqspi->tx_dma_chan);
+ if (tqspi->is_curr_dma_xfer && (tqspi->cur_direction & DATA_DIR_RX))
+ dmaengine_terminate_all(tqspi->rx_dma_chan);
+ tegra_qspi_handle_error(tqspi);
+ ret = -EIO;
+ goto complete_xfer;
+ }
+
+ if (tqspi->tx_status || tqspi->rx_status) {
+ tegra_qspi_handle_error(tqspi);
+ ret = -EIO;
+ goto complete_xfer;
+ }
+
+ msg->actual_length += xfer->len;
+
+complete_xfer:
+ if (ret < 0) {
+ tegra_qspi_transfer_end(spi);
+ spi_transfer_delay_exec(xfer);
+ goto exit;
+ }
+
+ if (list_is_last(&xfer->transfer_list, &msg->transfers)) {
+ /* de-activate CS after last transfer only when cs_change is not set */
+ if (!xfer->cs_change) {
+ tegra_qspi_transfer_end(spi);
+ spi_transfer_delay_exec(xfer);
+ }
+ } else if (xfer->cs_change) {
+ /* de-activated CS between the transfers only when cs_change is set */
+ tegra_qspi_transfer_end(spi);
+ spi_transfer_delay_exec(xfer);
+ }
+ }
+
+ ret = 0;
+exit:
+ msg->status = ret;
+ spi_finalize_current_message(master);
+ return ret;
+}
+
+static irqreturn_t handle_cpu_based_xfer(struct tegra_qspi *tqspi)
+{
+ struct spi_transfer *t = tqspi->curr_xfer;
+ unsigned long flags;
+
+ spin_lock_irqsave(&tqspi->lock, flags);
+
+ if (tqspi->tx_status || tqspi->rx_status) {
+ tegra_qspi_handle_error(tqspi);
+ complete(&tqspi->xfer_completion);
+ goto exit;
+ }
+
+ if (tqspi->cur_direction & DATA_DIR_RX)
+ tegra_qspi_read_rx_fifo_to_client_rxbuf(tqspi, t);
+
+ if (tqspi->cur_direction & DATA_DIR_TX)
+ tqspi->cur_pos = tqspi->cur_tx_pos;
+ else
+ tqspi->cur_pos = tqspi->cur_rx_pos;
+
+ if (tqspi->cur_pos == t->len) {
+ complete(&tqspi->xfer_completion);
+ goto exit;
+ }
+
+ tegra_qspi_calculate_curr_xfer_param(tqspi, t);
+ tegra_qspi_start_cpu_based_transfer(tqspi, t);
+exit:
+ spin_unlock_irqrestore(&tqspi->lock, flags);
+ return IRQ_HANDLED;
+}
+
+static irqreturn_t handle_dma_based_xfer(struct tegra_qspi *tqspi)
+{
+ struct spi_transfer *t = tqspi->curr_xfer;
+ unsigned int total_fifo_words;
+ unsigned long flags;
+ long wait_status;
+ int err = 0;
+
+ if (tqspi->cur_direction & DATA_DIR_TX) {
+ if (tqspi->tx_status) {
+ dmaengine_terminate_all(tqspi->tx_dma_chan);
+ err += 1;
+ } else {
+ wait_status = wait_for_completion_interruptible_timeout(
+ &tqspi->tx_dma_complete, QSPI_DMA_TIMEOUT);
+ if (wait_status <= 0) {
+ dmaengine_terminate_all(tqspi->tx_dma_chan);
+ dev_err(tqspi->dev, "failed TX DMA transfer\n");
+ err += 1;
+ }
+ }
+ }
+
+ if (tqspi->cur_direction & DATA_DIR_RX) {
+ if (tqspi->rx_status) {
+ dmaengine_terminate_all(tqspi->rx_dma_chan);
+ err += 2;
+ } else {
+ wait_status = wait_for_completion_interruptible_timeout(
+ &tqspi->rx_dma_complete, QSPI_DMA_TIMEOUT);
+ if (wait_status <= 0) {
+ dmaengine_terminate_all(tqspi->rx_dma_chan);
+ dev_err(tqspi->dev, "failed RX DMA transfer\n");
+ err += 2;
+ }
+ }
+ }
+
+ spin_lock_irqsave(&tqspi->lock, flags);
+
+ if (err) {
+ tegra_qspi_dma_unmap_xfer(tqspi, t);
+ tegra_qspi_handle_error(tqspi);
+ complete(&tqspi->xfer_completion);
+ goto exit;
+ }
+
+ if (tqspi->cur_direction & DATA_DIR_RX)
+ tegra_qspi_copy_qspi_rxbuf_to_client_rxbuf(tqspi, t);
+
+ if (tqspi->cur_direction & DATA_DIR_TX)
+ tqspi->cur_pos = tqspi->cur_tx_pos;
+ else
+ tqspi->cur_pos = tqspi->cur_rx_pos;
+
+ if (tqspi->cur_pos == t->len) {
+ tegra_qspi_dma_unmap_xfer(tqspi, t);
+ complete(&tqspi->xfer_completion);
+ goto exit;
+ }
+
+ tegra_qspi_dma_unmap_xfer(tqspi, t);
+
+ /* continue transfer in current message */
+ total_fifo_words = tegra_qspi_calculate_curr_xfer_param(tqspi, t);
+ if (total_fifo_words > QSPI_FIFO_DEPTH)
+ err = tegra_qspi_start_dma_based_transfer(tqspi, t);
+ else
+ err = tegra_qspi_start_cpu_based_transfer(tqspi, t);
+
+exit:
+ spin_unlock_irqrestore(&tqspi->lock, flags);
+ return IRQ_HANDLED;
+}
+
+static irqreturn_t tegra_qspi_isr_thread(int irq, void *context_data)
+{
+ struct tegra_qspi *tqspi = context_data;
+
+ tqspi->status_reg = tegra_qspi_readl(tqspi, QSPI_FIFO_STATUS);
+
+ if (tqspi->cur_direction & DATA_DIR_TX)
+ tqspi->tx_status = tqspi->status_reg & (QSPI_TX_FIFO_UNF | QSPI_TX_FIFO_OVF);
+
+ if (tqspi->cur_direction & DATA_DIR_RX)
+ tqspi->rx_status = tqspi->status_reg & (QSPI_RX_FIFO_OVF | QSPI_RX_FIFO_UNF);
+
+ tegra_qspi_mask_clear_irq(tqspi);
+
+ if (!tqspi->is_curr_dma_xfer)
+ return handle_cpu_based_xfer(tqspi);
+
+ return handle_dma_based_xfer(tqspi);
+}
+
+static const struct of_device_id tegra_qspi_of_match[] = {
+ { .compatible = "nvidia,tegra210-qspi", },
+ { .compatible = "nvidia,tegra186-qspi", },
+ { .compatible = "nvidia,tegra194-qspi", },
+ {}
+};
+
+MODULE_DEVICE_TABLE(of, tegra_qspi_of_match);
+
+static int tegra_qspi_probe(struct platform_device *pdev)
+{
+ struct spi_master *master;
+ struct tegra_qspi *tqspi;
+ struct resource *r;
+ int ret, qspi_irq;
+ int bus_num;
+
+ master = devm_spi_alloc_master(&pdev->dev, sizeof(*tqspi));
+ if (!master) {
+ dev_err(&pdev->dev, "failed to allocate spi_master\n");
+ return -ENOMEM;
+ }
+
+ platform_set_drvdata(pdev, master);
+ tqspi = spi_master_get_devdata(master);
+
+ master->mode_bits = SPI_MODE_0 | SPI_MODE_3 | SPI_CS_HIGH |
+ SPI_TX_DUAL | SPI_RX_DUAL | SPI_TX_QUAD | SPI_RX_QUAD;
+ master->bits_per_word_mask = SPI_BPW_MASK(32) | SPI_BPW_MASK(16) | SPI_BPW_MASK(8);
+ master->setup = tegra_qspi_setup;
+ master->cleanup = tegra_qspi_cleanup;
+ master->transfer_one_message = tegra_qspi_transfer_one_message;
+ master->num_chipselect = 1;
+ master->auto_runtime_pm = true;
+
+ bus_num = of_alias_get_id(pdev->dev.of_node, "spi");
+ if (bus_num >= 0)
+ master->bus_num = bus_num;
+
+ tqspi->master = master;
+ tqspi->dev = &pdev->dev;
+ spin_lock_init(&tqspi->lock);
+
+ r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ tqspi->base = devm_ioremap_resource(&pdev->dev, r);
+ if (IS_ERR(tqspi->base))
+ return PTR_ERR(tqspi->base);
+
+ tqspi->phys = r->start;
+ qspi_irq = platform_get_irq(pdev, 0);
+ tqspi->irq = qspi_irq;
+
+ tqspi->clk = devm_clk_get(&pdev->dev, "qspi");
+ if (IS_ERR(tqspi->clk)) {
+ ret = PTR_ERR(tqspi->clk);
+ dev_err(&pdev->dev, "failed to get clock: %d\n", ret);
+ return ret;
+ }
+
+ tqspi->rst = devm_reset_control_get_exclusive(&pdev->dev, NULL);
+ if (IS_ERR(tqspi->rst)) {
+ ret = PTR_ERR(tqspi->rst);
+ dev_err(&pdev->dev, "failed to get reset control: %d\n", ret);
+ return ret;
+ }
+
+ tqspi->max_buf_size = QSPI_FIFO_DEPTH << 2;
+ tqspi->dma_buf_size = DEFAULT_QSPI_DMA_BUF_LEN;
+
+ ret = tegra_qspi_init_dma(tqspi);
+ if (ret < 0)
+ return ret;
+
+ if (tqspi->use_dma)
+ tqspi->max_buf_size = tqspi->dma_buf_size;
+
+ init_completion(&tqspi->tx_dma_complete);
+ init_completion(&tqspi->rx_dma_complete);
+ init_completion(&tqspi->xfer_completion);
+
+ pm_runtime_enable(&pdev->dev);
+ ret = pm_runtime_resume_and_get(&pdev->dev);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "failed to get runtime PM: %d\n", ret);
+ goto exit_pm_disable;
+ }
+
+ reset_control_assert(tqspi->rst);
+ udelay(2);
+ reset_control_deassert(tqspi->rst);
+
+ tqspi->def_command1_reg = QSPI_M_S | QSPI_CS_SW_HW | QSPI_CS_SW_VAL;
+ tegra_qspi_writel(tqspi, tqspi->def_command1_reg, QSPI_COMMAND1);
+ tqspi->spi_cs_timing1 = tegra_qspi_readl(tqspi, QSPI_CS_TIMING1);
+ tqspi->spi_cs_timing2 = tegra_qspi_readl(tqspi, QSPI_CS_TIMING2);
+ tqspi->def_command2_reg = tegra_qspi_readl(tqspi, QSPI_COMMAND2);
+
+ pm_runtime_put(&pdev->dev);
+
+ ret = request_threaded_irq(tqspi->irq, NULL,
+ tegra_qspi_isr_thread, IRQF_ONESHOT,
+ dev_name(&pdev->dev), tqspi);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "failed to request IRQ#%u: %d\n", tqspi->irq, ret);
+ goto exit_pm_disable;
+ }
+
+ master->dev.of_node = pdev->dev.of_node;
+ ret = spi_register_master(master);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "failed to register master: %d\n", ret);
+ goto exit_free_irq;
+ }
+
+ return 0;
+
+exit_free_irq:
+ free_irq(qspi_irq, tqspi);
+exit_pm_disable:
+ pm_runtime_disable(&pdev->dev);
+ tegra_qspi_deinit_dma(tqspi);
+ return ret;
+}
+
+static int tegra_qspi_remove(struct platform_device *pdev)
+{
+ struct spi_master *master = platform_get_drvdata(pdev);
+ struct tegra_qspi *tqspi = spi_master_get_devdata(master);
+
+ spi_unregister_master(master);
+ free_irq(tqspi->irq, tqspi);
+ tegra_qspi_deinit_dma(tqspi);
+ pm_runtime_disable(&pdev->dev);
+
+ return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int tegra_qspi_suspend(struct device *dev)
+{
+ struct spi_master *master = dev_get_drvdata(dev);
+
+ return spi_master_suspend(master);
+}
+
+static int tegra_qspi_resume(struct device *dev)
+{
+ struct spi_master *master = dev_get_drvdata(dev);
+ struct tegra_qspi *tqspi = spi_master_get_devdata(master);
+ int ret;
+
+ ret = pm_runtime_resume_and_get(dev);
+ if (ret < 0) {
+ dev_err(dev, "failed to get runtime PM: %d\n", ret);
+ return ret;
+ }
+
+ tegra_qspi_writel(tqspi, tqspi->command1_reg, QSPI_COMMAND1);
+ tegra_qspi_writel(tqspi, tqspi->def_command2_reg, QSPI_COMMAND2);
+ pm_runtime_put(dev);
+
+ return spi_master_resume(master);
+}
+#endif
+
+static int tegra_qspi_runtime_suspend(struct device *dev)
+{
+ struct spi_master *master = dev_get_drvdata(dev);
+ struct tegra_qspi *tqspi = spi_master_get_devdata(master);
+
+ /* flush all write which are in PPSB queue by reading back */
+ tegra_qspi_readl(tqspi, QSPI_COMMAND1);
+
+ clk_disable_unprepare(tqspi->clk);
+
+ return 0;
+}
+
+static int tegra_qspi_runtime_resume(struct device *dev)
+{
+ struct spi_master *master = dev_get_drvdata(dev);
+ struct tegra_qspi *tqspi = spi_master_get_devdata(master);
+ int ret;
+
+ ret = clk_prepare_enable(tqspi->clk);
+ if (ret < 0)
+ dev_err(tqspi->dev, "failed to enable clock: %d\n", ret);
+
+ return ret;
+}
+
+static const struct dev_pm_ops tegra_qspi_pm_ops = {
+ SET_RUNTIME_PM_OPS(tegra_qspi_runtime_suspend, tegra_qspi_runtime_resume, NULL)
+ SET_SYSTEM_SLEEP_PM_OPS(tegra_qspi_suspend, tegra_qspi_resume)
+};
+
+static struct platform_driver tegra_qspi_driver = {
+ .driver = {
+ .name = "tegra-qspi",
+ .pm = &tegra_qspi_pm_ops,
+ .of_match_table = tegra_qspi_of_match,
+ },
+ .probe = tegra_qspi_probe,
+ .remove = tegra_qspi_remove,
+};
+module_platform_driver(tegra_qspi_driver);
+
+MODULE_ALIAS("platform:qspi-tegra");
+MODULE_DESCRIPTION("NVIDIA Tegra QSPI Controller Driver");
+MODULE_AUTHOR("Sowjanya Komatineni <skomatineni@xxxxxxxxxx>");
+MODULE_LICENSE("GPL v2");
--
2.7.4