+/*
+ * (C) Copyright 2017 Whitebox Systems / Northend Systems B.V.
+ * S.J.R. van Schaik <stephan@whiteboxsystems.nl>
+ * M.B.W. Wajer <merlijn@whiteboxsystems.nl>
+ *
+ * (C) Copyright 2017 Olimex Ltd..
+ * Stefan Mavrodiev <stefan@olimex.com>
+ *
+ * Based on linux spi driver. Original copyright follows:
+ * linux/drivers/spi/spi-sun4i.c
+ *
+ * Copyright (C) 2012 - 2014 Allwinner Tech
+ * Pan Nan <pannan@allwinnertech.com>
+ *
+ * Copyright (C) 2014 Maxime Ripard
+ * Maxime Ripard <maxime.ripard@free-electrons.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <spi.h>
+#include <errno.h>
+#include <fdt_support.h>
+#include <wait_bit.h>
+
+#include <asm/bitops.h>
+#include <asm/gpio.h>
+#include <asm/io.h>
+
+#include <asm/arch/clock.h>
+
+#define SUN4I_FIFO_DEPTH 64
+
+#define SUN4I_RXDATA_REG 0x00
+
+#define SUN4I_TXDATA_REG 0x04
+
+#define SUN4I_CTL_REG 0x08
+#define SUN4I_CTL_ENABLE BIT(0)
+#define SUN4I_CTL_MASTER BIT(1)
+#define SUN4I_CTL_CPHA BIT(2)
+#define SUN4I_CTL_CPOL BIT(3)
+#define SUN4I_CTL_CS_ACTIVE_LOW BIT(4)
+#define SUN4I_CTL_LMTF BIT(6)
+#define SUN4I_CTL_TF_RST BIT(8)
+#define SUN4I_CTL_RF_RST BIT(9)
+#define SUN4I_CTL_XCH_MASK 0x0400
+#define SUN4I_CTL_XCH BIT(10)
+#define SUN4I_CTL_CS_MASK 0x3000
+#define SUN4I_CTL_CS(cs) (((cs) << 12) & SUN4I_CTL_CS_MASK)
+#define SUN4I_CTL_DHB BIT(15)
+#define SUN4I_CTL_CS_MANUAL BIT(16)
+#define SUN4I_CTL_CS_LEVEL BIT(17)
+#define SUN4I_CTL_TP BIT(18)
+
+#define SUN4I_INT_CTL_REG 0x0c
+#define SUN4I_INT_CTL_RF_F34 BIT(4)
+#define SUN4I_INT_CTL_TF_E34 BIT(12)
+#define SUN4I_INT_CTL_TC BIT(16)
+
+#define SUN4I_INT_STA_REG 0x10
+
+#define SUN4I_DMA_CTL_REG 0x14
+
+#define SUN4I_WAIT_REG 0x18
+
+#define SUN4I_CLK_CTL_REG 0x1c
+#define SUN4I_CLK_CTL_CDR2_MASK 0xff
+#define SUN4I_CLK_CTL_CDR2(div) ((div) & SUN4I_CLK_CTL_CDR2_MASK)
+#define SUN4I_CLK_CTL_CDR1_MASK 0xf
+#define SUN4I_CLK_CTL_CDR1(div) (((div) & SUN4I_CLK_CTL_CDR1_MASK) << 8)
+#define SUN4I_CLK_CTL_DRS BIT(12)
+
+#define SUN4I_MAX_XFER_SIZE 0xffffff
+
+#define SUN4I_BURST_CNT_REG 0x20
+#define SUN4I_BURST_CNT(cnt) ((cnt) & SUN4I_MAX_XFER_SIZE)
+
+#define SUN4I_XMIT_CNT_REG 0x24
+#define SUN4I_XMIT_CNT(cnt) ((cnt) & SUN4I_MAX_XFER_SIZE)
+
+#define SUN4I_FIFO_STA_REG 0x28
+#define SUN4I_FIFO_STA_RF_CNT_MASK 0x7f
+#define SUN4I_FIFO_STA_RF_CNT_BITS 0
+#define SUN4I_FIFO_STA_TF_CNT_MASK 0x7f
+#define SUN4I_FIFO_STA_TF_CNT_BITS 16
+
+#define SUN4I_SPI_MAX_RATE 24000000
+#define SUN4I_SPI_MIN_RATE 3000
+#define SUN4I_SPI_DEFAULT_RATE 1000000
+#define SUN4I_SPI_TIMEOUT_US 1000000
+
+/* sun4i spi register set */
+struct sun4i_spi_regs {
+ u32 rxdata;
+ u32 txdata;
+ u32 ctl;
+ u32 intctl;
+ u32 st;
+ u32 dmactl;
+ u32 wait;
+ u32 cctl;
+ u32 bc;
+ u32 tc;
+ u32 fifo_sta;
+};
+
+struct sun4i_spi_platdata {
+ u32 base_addr;
+ u32 max_hz;
+};
+
+struct sun4i_spi_priv {
+ struct sun4i_spi_regs *regs;
+ u32 freq;
+ u32 mode;
+
+ const u8 *tx_buf;
+ u8 *rx_buf;
+};
+
+DECLARE_GLOBAL_DATA_PTR;
+
+static inline void sun4i_spi_drain_fifo(struct sun4i_spi_priv *priv, int len)
+{
+ u8 byte;
+
+ while (len--) {
+ byte = readb(&priv->regs->rxdata);
+ *priv->rx_buf++ = byte;
+ }
+}
+
+static inline void sun4i_spi_fill_fifo(struct sun4i_spi_priv *priv, int len)
+{
+ u8 byte;
+
+ while (len--) {
+ byte = priv->tx_buf ? *priv->tx_buf++ : 0;
+ writeb(byte, &priv->regs->txdata);
+ }
+}
+
+static void sun4i_spi_set_cs(struct udevice *bus, u8 cs, bool enable)
+{
+ struct sun4i_spi_priv *priv = dev_get_priv(bus);
+ u32 reg;
+
+ reg = readl(&priv->regs->ctl);
+
+ reg &= ~SUN4I_CTL_CS_MASK;
+ reg |= SUN4I_CTL_CS(cs);
+
+ if (enable)
+ reg &= ~SUN4I_CTL_CS_LEVEL;
+ else
+ reg |= SUN4I_CTL_CS_LEVEL;
+
+ writel(reg, &priv->regs->ctl);
+}
+
+static int sun4i_spi_parse_pins(struct udevice *dev)
+{
+ const void *fdt = gd->fdt_blob;
+ const char *pin_name;
+ const fdt32_t *list;
+ u32 phandle;
+ int drive, pull = 0, pin, i;
+ int offset;
+ int size;
+
+ list = fdt_getprop(fdt, dev_of_offset(dev), "pinctrl-0", &size);
+ if (!list) {
+ printf("WARNING: sun4i_spi: cannot find pinctrl-0 node\n");
+ return -EINVAL;
+ }
+
+ while (size) {
+ phandle = fdt32_to_cpu(*list++);
+ size -= sizeof(*list);
+
+ offset = fdt_node_offset_by_phandle(fdt, phandle);
+ if (offset < 0)
+ return offset;
+
+ drive = fdt_getprop_u32_default_node(fdt, offset, 0,
+ "drive-strength", 0);
+ if (drive) {
+ if (drive <= 10)
+ drive = 0;
+ else if (drive <= 20)
+ drive = 1;
+ else if (drive <= 30)
+ drive = 2;
+ else
+ drive = 3;
+ } else {
+ drive = fdt_getprop_u32_default_node(fdt, offset, 0,
+ "allwinner,drive",
+ 0);
+ drive = min(drive, 3);
+ }
+
+ if (fdt_get_property(fdt, offset, "bias-disable", NULL))
+ pull = 0;
+ else if (fdt_get_property(fdt, offset, "bias-pull-up", NULL))
+ pull = 1;
+ else if (fdt_get_property(fdt, offset, "bias-pull-down", NULL))
+ pull = 2;
+ else
+ pull = fdt_getprop_u32_default_node(fdt, offset, 0,
+ "allwinner,pull",
+ 0);
+ pull = min(pull, 2);
+
+ for (i = 0; ; i++) {
+ pin_name = fdt_stringlist_get(fdt, offset,
+ "pins", i, NULL);
+ if (!pin_name) {
+ pin_name = fdt_stringlist_get(fdt, offset,
+ "allwinner,pins",
+ i, NULL);
+ if (!pin_name)
+ break;
+ }
+
+ pin = name_to_gpio(pin_name);
+ if (pin < 0)
+ break;
+
+ sunxi_gpio_set_cfgpin(pin, SUNXI_GPC_SPI0);
+ sunxi_gpio_set_drv(pin, drive);
+ sunxi_gpio_set_pull(pin, pull);
+ }
+ }
+ return 0;
+}
+
+static inline void sun4i_spi_enable_clock(void)
+{
+ struct sunxi_ccm_reg *const ccm =
+ (struct sunxi_ccm_reg *const)SUNXI_CCM_BASE;
+
+ setbits_le32(&ccm->ahb_gate0, (1 << AHB_GATE_OFFSET_SPI0));
+ writel((1 << 31), &ccm->spi0_clk_cfg);
+}
+
+static int sun4i_spi_ofdata_to_platdata(struct udevice *bus)
+{
+ struct sun4i_spi_platdata *plat = dev_get_platdata(bus);
+ int node = dev_of_offset(bus);
+
+ plat->base_addr = devfdt_get_addr(bus);
+ plat->max_hz = fdtdec_get_int(gd->fdt_blob, node,
+ "spi-max-frequency",
+ SUN4I_SPI_DEFAULT_RATE);
+
+ if (plat->max_hz > SUN4I_SPI_MAX_RATE)
+ plat->max_hz = SUN4I_SPI_MAX_RATE;
+
+ return 0;
+}
+
+static int sun4i_spi_probe(struct udevice *bus)
+{
+ struct sun4i_spi_platdata *plat = dev_get_platdata(bus);
+ struct sun4i_spi_priv *priv = dev_get_priv(bus);
+
+ sun4i_spi_enable_clock();
+ sun4i_spi_parse_pins(bus);
+
+ priv->regs = (struct sun4i_spi_regs *)(uintptr_t)plat->base_addr;
+ priv->freq = plat->max_hz;
+
+ return 0;
+}
+
+static int sun4i_spi_claim_bus(struct udevice *dev)
+{
+ struct sun4i_spi_priv *priv = dev_get_priv(dev->parent);
+
+ writel(SUN4I_CTL_ENABLE | SUN4I_CTL_MASTER | SUN4I_CTL_TP |
+ SUN4I_CTL_CS_MANUAL | SUN4I_CTL_CS_ACTIVE_LOW,
+ &priv->regs->ctl);
+ return 0;
+}
+
+static int sun4i_spi_release_bus(struct udevice *dev)
+{
+ struct sun4i_spi_priv *priv = dev_get_priv(dev->parent);
+ u32 reg;
+
+ reg = readl(&priv->regs->ctl);
+ reg &= ~SUN4I_CTL_ENABLE;
+ writel(reg, &priv->regs->ctl);
+
+ return 0;
+}
+
+static int sun4i_spi_xfer(struct udevice *dev, unsigned int bitlen,
+ const void *dout, void *din, unsigned long flags)
+{
+ struct udevice *bus = dev->parent;
+ struct sun4i_spi_priv *priv = dev_get_priv(bus);
+ struct dm_spi_slave_platdata *slave_plat = dev_get_parent_platdata(dev);
+
+ u32 len = bitlen / 8;
+ u32 reg;
+ u8 nbytes;
+ int ret;
+
+ priv->tx_buf = dout;
+ priv->rx_buf = din;
+
+ if (bitlen % 8) {
+ debug("%s: non byte-aligned SPI transfer.\n", __func__);
+ return -ENAVAIL;
+ }
+
+ if (flags & SPI_XFER_BEGIN)
+ sun4i_spi_set_cs(bus, slave_plat->cs, true);
+
+ reg = readl(&priv->regs->ctl);
+
+ /* Reset FIFOs */
+ writel(reg | SUN4I_CTL_RF_RST | SUN4I_CTL_TF_RST, &priv->regs->ctl);
+
+ while (len) {
+ /* Setup the transfer now... */
+ nbytes = min(len, (u32)(SUN4I_FIFO_DEPTH - 1));
+
+ /* Setup the counters */
+ writel(SUN4I_BURST_CNT(nbytes), &priv->regs->bc);
+ writel(SUN4I_XMIT_CNT(nbytes), &priv->regs->tc);
+
+ /* Fill the TX FIFO */
+ sun4i_spi_fill_fifo(priv, nbytes);
+
+ /* Start the transfer */
+ reg = readl(&priv->regs->ctl);
+ writel(reg | SUN4I_CTL_XCH, &priv->regs->ctl);
+
+ /* Wait transfer to complete */
+ ret = wait_for_bit_le32(&priv->regs->ctl, SUN4I_CTL_XCH_MASK,
+ false, SUN4I_SPI_TIMEOUT_US, false);
+ if (ret) {
+ printf("ERROR: sun4i_spi: Timeout transferring data\n");
+ sun4i_spi_set_cs(bus, slave_plat->cs, false);
+ return ret;
+ }
+
+ /* Drain the RX FIFO */
+ sun4i_spi_drain_fifo(priv, nbytes);
+
+ len -= nbytes;
+ }
+
+ if (flags & SPI_XFER_END)
+ sun4i_spi_set_cs(bus, slave_plat->cs, false);
+
+ return 0;
+}
+
+static int sun4i_spi_set_speed(struct udevice *dev, uint speed)
+{
+ struct sun4i_spi_platdata *plat = dev_get_platdata(dev);
+ struct sun4i_spi_priv *priv = dev_get_priv(dev);
+ unsigned int div;
+ u32 reg;
+
+ if (speed > plat->max_hz)
+ speed = plat->max_hz;
+
+ if (speed < SUN4I_SPI_MIN_RATE)
+ speed = SUN4I_SPI_MIN_RATE;
+ /*
+ * Setup clock divider.
+ *
+ * We have two choices there. Either we can use the clock
+ * divide rate 1, which is calculated thanks to this formula:
+ * SPI_CLK = MOD_CLK / (2 ^ (cdr + 1))
+ * Or we can use CDR2, which is calculated with the formula:
+ * SPI_CLK = MOD_CLK / (2 * (cdr + 1))
+ * Whether we use the former or the latter is set through the
+ * DRS bit.
+ *
+ * First try CDR2, and if we can't reach the expected
+ * frequency, fall back to CDR1.
+ */
+
+ div = SUN4I_SPI_MAX_RATE / (2 * speed);
+ reg = readl(&priv->regs->cctl);
+
+ if (div <= (SUN4I_CLK_CTL_CDR2_MASK + 1)) {
+ if (div > 0)
+ div--;
+
+ reg &= ~(SUN4I_CLK_CTL_CDR2_MASK | SUN4I_CLK_CTL_DRS);
+ reg |= SUN4I_CLK_CTL_CDR2(div) | SUN4I_CLK_CTL_DRS;
+ } else {
+ div = __ilog2(SUN4I_SPI_MAX_RATE) - __ilog2(speed);
+ reg &= ~((SUN4I_CLK_CTL_CDR1_MASK << 8) | SUN4I_CLK_CTL_DRS);
+ reg |= SUN4I_CLK_CTL_CDR1(div);
+ }
+
+ priv->freq = speed;
+ writel(reg, &priv->regs->cctl);
+
+ return 0;
+}
+
+static int sun4i_spi_set_mode(struct udevice *dev, uint mode)
+{
+ struct sun4i_spi_priv *priv = dev_get_priv(dev);
+ u32 reg;
+
+ reg = readl(&priv->regs->ctl);
+ reg &= ~(SUN4I_CTL_CPOL | SUN4I_CTL_CPHA);
+
+ if (mode & SPI_CPOL)
+ reg |= SUN4I_CTL_CPOL;
+
+ if (mode & SPI_CPHA)
+ reg |= SUN4I_CTL_CPHA;
+
+ priv->mode = mode;
+ writel(reg, &priv->regs->ctl);
+
+ return 0;
+}
+
+static const struct dm_spi_ops sun4i_spi_ops = {
+ .claim_bus = sun4i_spi_claim_bus,
+ .release_bus = sun4i_spi_release_bus,
+ .xfer = sun4i_spi_xfer,
+ .set_speed = sun4i_spi_set_speed,
+ .set_mode = sun4i_spi_set_mode,
+};
+
+static const struct udevice_id sun4i_spi_ids[] = {
+ { .compatible = "allwinner,sun4i-a10-spi" },
+ { }
+};
+
+U_BOOT_DRIVER(sun4i_spi) = {
+ .name = "sun4i_spi",
+ .id = UCLASS_SPI,
+ .of_match = sun4i_spi_ids,
+ .ops = &sun4i_spi_ops,
+ .ofdata_to_platdata = sun4i_spi_ofdata_to_platdata,
+ .platdata_auto_alloc_size = sizeof(struct sun4i_spi_platdata),
+ .priv_auto_alloc_size = sizeof(struct sun4i_spi_priv),
+ .probe = sun4i_spi_probe,
+};
projects / platform / kernel / u-boot.git / commitdiff