spi: Add zynq spi controller driver
Zynq spi controller driver supports 2 buses and
3 chipselects on each bus.
Signed-off-by: Jagannadha Sutradharudu Teki <jaganna@xilinx.com>
Acked-by: Siva Durga Prasad Paladugu <sivadur@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
diff --git a/drivers/spi/zynq_spi.c b/drivers/spi/zynq_spi.c
new file mode 100644
index 0000000..5da8759
--- /dev/null
+++ b/drivers/spi/zynq_spi.c
@@ -0,0 +1,280 @@
+/*
+ * (C) Copyright 2013 Inc.
+ *
+ * Xilinx Zynq PS SPI controller driver (master mode only)
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#include <config.h>
+#include <common.h>
+#include <malloc.h>
+#include <spi.h>
+#include <asm/io.h>
+#include <asm/arch/hardware.h>
+
+/* zynq spi register bit masks ZYNQ_SPI_<REG>_<BIT>_MASK */
+#define ZYNQ_SPI_CR_MSA_MASK (1 << 15) /* Manual start enb */
+#define ZYNQ_SPI_CR_MCS_MASK (1 << 14) /* Manual chip select */
+#define ZYNQ_SPI_CR_CS_MASK (0xF << 10) /* Chip select */
+#define ZYNQ_SPI_CR_BRD_MASK (0x7 << 3) /* Baud rate div */
+#define ZYNQ_SPI_CR_CPHA_MASK (1 << 2) /* Clock phase */
+#define ZYNQ_SPI_CR_CPOL_MASK (1 << 1) /* Clock polarity */
+#define ZYNQ_SPI_CR_MSTREN_MASK (1 << 0) /* Mode select */
+#define ZYNQ_SPI_IXR_RXNEMPTY_MASK (1 << 4) /* RX_FIFO_not_empty */
+#define ZYNQ_SPI_IXR_TXOW_MASK (1 << 2) /* TX_FIFO_not_full */
+#define ZYNQ_SPI_IXR_ALL_MASK 0x7F /* All IXR bits */
+#define ZYNQ_SPI_ENR_SPI_EN_MASK (1 << 0) /* SPI Enable */
+
+#define ZYNQ_SPI_FIFO_DEPTH 128
+#ifndef CONFIG_SYS_ZYNQ_SPI_WAIT
+#define CONFIG_SYS_ZYNQ_SPI_WAIT (CONFIG_SYS_HZ/100) /* 10 ms */
+#endif
+
+/* zynq spi register set */
+struct zynq_spi_regs {
+ u32 cr; /* 0x00 */
+ u32 isr; /* 0x04 */
+ u32 ier; /* 0x08 */
+ u32 idr; /* 0x0C */
+ u32 imr; /* 0x10 */
+ u32 enr; /* 0x14 */
+ u32 dr; /* 0x18 */
+ u32 txdr; /* 0x1C */
+ u32 rxdr; /* 0x20 */
+};
+
+/* zynq spi slave */
+struct zynq_spi_slave {
+ struct spi_slave slave;
+ struct zynq_spi_regs *base;
+ u8 mode;
+ u8 fifo_depth;
+ u32 speed_hz;
+ u32 input_hz;
+ u32 req_hz;
+};
+
+static inline struct zynq_spi_slave *to_zynq_spi_slave(struct spi_slave *slave)
+{
+ return container_of(slave, struct zynq_spi_slave, slave);
+}
+
+static inline struct zynq_spi_regs *get_zynq_spi_base(int dev)
+{
+ if (dev)
+ return (struct zynq_spi_regs *)ZYNQ_SPI_BASEADDR1;
+ else
+ return (struct zynq_spi_regs *)ZYNQ_SPI_BASEADDR0;
+}
+
+static void zynq_spi_init_hw(struct zynq_spi_slave *zslave)
+{
+ u32 confr;
+
+ /* Disable SPI */
+ writel(~ZYNQ_SPI_ENR_SPI_EN_MASK, &zslave->base->enr);
+
+ /* Disable Interrupts */
+ writel(ZYNQ_SPI_IXR_ALL_MASK, &zslave->base->idr);
+
+ /* Clear RX FIFO */
+ while (readl(&zslave->base->isr) &
+ ZYNQ_SPI_IXR_RXNEMPTY_MASK)
+ readl(&zslave->base->rxdr);
+
+ /* Clear Interrupts */
+ writel(ZYNQ_SPI_IXR_ALL_MASK, &zslave->base->isr);
+
+ /* Manual slave select and Auto start */
+ confr = ZYNQ_SPI_CR_MCS_MASK | ZYNQ_SPI_CR_CS_MASK |
+ ZYNQ_SPI_CR_MSTREN_MASK;
+ confr &= ~ZYNQ_SPI_CR_MSA_MASK;
+ writel(confr, &zslave->base->cr);
+
+ /* Enable SPI */
+ writel(ZYNQ_SPI_ENR_SPI_EN_MASK, &zslave->base->enr);
+}
+
+int spi_cs_is_valid(unsigned int bus, unsigned int cs)
+{
+ /* 2 bus with 3 chipselect */
+ return bus < 2 && cs < 3;
+}
+
+void spi_cs_activate(struct spi_slave *slave)
+{
+ struct zynq_spi_slave *zslave = to_zynq_spi_slave(slave);
+ u32 cr;
+
+ debug("spi_cs_activate: 0x%08x\n", (u32)slave);
+
+ clrbits_le32(&zslave->base->cr, ZYNQ_SPI_CR_CS_MASK);
+ cr = readl(&zslave->base->cr);
+ /*
+ * CS cal logic: CS[13:10]
+ * xxx0 - cs0
+ * xx01 - cs1
+ * x011 - cs2
+ */
+ cr |= (~(0x1 << slave->cs) << 10) & ZYNQ_SPI_CR_CS_MASK;
+ writel(cr, &zslave->base->cr);
+}
+
+void spi_cs_deactivate(struct spi_slave *slave)
+{
+ struct zynq_spi_slave *zslave = to_zynq_spi_slave(slave);
+
+ debug("spi_cs_deactivate: 0x%08x\n", (u32)slave);
+
+ setbits_le32(&zslave->base->cr, ZYNQ_SPI_CR_CS_MASK);
+}
+
+void spi_init()
+{
+ /* nothing to do */
+}
+
+struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs,
+ unsigned int max_hz, unsigned int mode)
+{
+ struct zynq_spi_slave *zslave;
+
+ if (!spi_cs_is_valid(bus, cs))
+ return NULL;
+
+ zslave = spi_alloc_slave(struct zynq_spi_slave, bus, cs);
+ if (!zslave) {
+ printf("SPI_error: Fail to allocate zynq_spi_slave\n");
+ return NULL;
+ }
+
+ zslave->base = get_zynq_spi_base(bus);
+ zslave->mode = mode;
+ zslave->fifo_depth = ZYNQ_SPI_FIFO_DEPTH;
+ zslave->input_hz = 166666700;
+ zslave->speed_hz = zslave->input_hz / 2;
+ zslave->req_hz = max_hz;
+
+ /* init the zynq spi hw */
+ zynq_spi_init_hw(zslave);
+
+ return &zslave->slave;
+}
+
+void spi_free_slave(struct spi_slave *slave)
+{
+ struct zynq_spi_slave *zslave = to_zynq_spi_slave(slave);
+
+ debug("spi_free_slave: 0x%08x\n", (u32)slave);
+ free(zslave);
+}
+
+int spi_claim_bus(struct spi_slave *slave)
+{
+ struct zynq_spi_slave *zslave = to_zynq_spi_slave(slave);
+ u32 confr = 0;
+ u8 baud_rate_val = 0;
+
+ writel(~ZYNQ_SPI_ENR_SPI_EN_MASK, &zslave->base->enr);
+
+ /* Set the SPI Clock phase and polarities */
+ confr = readl(&zslave->base->cr);
+ confr &= ~(ZYNQ_SPI_CR_CPHA_MASK | ZYNQ_SPI_CR_CPOL_MASK);
+ if (zslave->mode & SPI_CPHA)
+ confr |= ZYNQ_SPI_CR_CPHA_MASK;
+ if (zslave->mode & SPI_CPOL)
+ confr |= ZYNQ_SPI_CR_CPOL_MASK;
+
+ /* Set the clock frequency */
+ if (zslave->req_hz == 0) {
+ /* Set baudrate x8, if the req_hz is 0 */
+ baud_rate_val = 0x2;
+ } else if (zslave->speed_hz != zslave->req_hz) {
+ while ((baud_rate_val < 8) &&
+ ((zslave->input_hz /
+ (2 << baud_rate_val)) > zslave->req_hz))
+ baud_rate_val++;
+ zslave->speed_hz = zslave->req_hz / (2 << baud_rate_val);
+ }
+ confr &= ~ZYNQ_SPI_CR_BRD_MASK;
+ confr |= (baud_rate_val << 3);
+ writel(confr, &zslave->base->cr);
+
+ writel(ZYNQ_SPI_ENR_SPI_EN_MASK, &zslave->base->enr);
+
+ return 0;
+}
+
+void spi_release_bus(struct spi_slave *slave)
+{
+ struct zynq_spi_slave *zslave = to_zynq_spi_slave(slave);
+
+ debug("spi_release_bus: 0x%08x\n", (u32)slave);
+ writel(~ZYNQ_SPI_ENR_SPI_EN_MASK, &zslave->base->enr);
+}
+
+int spi_xfer(struct spi_slave *slave, unsigned int bitlen, const void *dout,
+ void *din, unsigned long flags)
+{
+ struct zynq_spi_slave *zslave = to_zynq_spi_slave(slave);
+ u32 len = bitlen / 8;
+ u32 tx_len = len, rx_len = len, tx_tvl;
+ const u8 *tx_buf = dout;
+ u8 *rx_buf = din, buf;
+ u32 ts, status;
+
+ debug("spi_xfer: bus:%i cs:%i bitlen:%i len:%i flags:%lx\n",
+ slave->bus, slave->cs, bitlen, len, flags);
+
+ if (bitlen == 0)
+ return -1;
+
+ if (bitlen % 8) {
+ debug("spi_xfer: Non byte aligned SPI transfer\n");
+ return -1;
+ }
+
+ if (flags & SPI_XFER_BEGIN)
+ spi_cs_activate(slave);
+
+ while (rx_len > 0) {
+ /* Write the data into TX FIFO - tx threshold is fifo_depth */
+ tx_tvl = 0;
+ while ((tx_tvl < zslave->fifo_depth) && tx_len) {
+ if (tx_buf)
+ buf = *tx_buf++;
+ else
+ buf = 0;
+ writel(buf, &zslave->base->txdr);
+ tx_len--;
+ tx_tvl++;
+ }
+
+ /* Check TX FIFO completion */
+ ts = get_timer(0);
+ status = readl(&zslave->base->isr);
+ while (!(status & ZYNQ_SPI_IXR_TXOW_MASK)) {
+ if (get_timer(ts) > CONFIG_SYS_ZYNQ_SPI_WAIT) {
+ printf("spi_xfer: Timeout! TX FIFO not full\n");
+ return -1;
+ }
+ status = readl(&zslave->base->isr);
+ }
+
+ /* Read the data from RX FIFO */
+ status = readl(&zslave->base->isr);
+ while (status & ZYNQ_SPI_IXR_RXNEMPTY_MASK) {
+ buf = readl(&zslave->base->rxdr);
+ if (rx_buf)
+ *rx_buf++ = buf;
+ status = readl(&zslave->base->isr);
+ rx_len--;
+ }
+ }
+
+ if (flags & SPI_XFER_END)
+ spi_cs_deactivate(slave);
+
+ return 0;
+}