[U-Boot] [PATCH v8 7/9] drivers: spi: add spi support for QCA/Atheros ath79 SOCs
Wills Wang
wills.wang at live.com
Wed Mar 16 09:59:58 CET 2016
This patch add a compatible spi driver for ath79 series SOC.
Reviewed-by: Thomas Chou <thomas at wytron.com.tw>
Reviewed-by: Daniel Schwierzeck <daniel.schwierzeck at gmail.com>
Signed-off-by: Wills Wang <wills.wang at live.com>
---
Changes in v8:
- Remove ath79_spi_write/read
- Use pinctrl for spi
- Add Kconfig dependence for spi option
- Use dev_get_parent
Changes in v7:
- Define spi_cs_activate/spi_cs_deactivate
- Rename MHZ to ATH79_SPI_MHZ
- Use clrsetbits_32
Changes in v6:
- Add rrw_delay in ath79_spi_priv for more accurate timing
- Remove ath79_spi_delay
- Calculate delay in ath79_spi_set_speed
Changes in v5:
- remove ar933x_spi_platdata
- Import document "spi-ath79.txt" from kernel
- Add delay for bitbang operation
Changes in v4:
- Use get_bus_freq instead of hardcode in SPI driver
Changes in v3:
- Convert spi driver to driver model
Changes in v2:
- Add a compatible spi driver
doc/device-tree-bindings/spi/spi-ath79.txt | 19 +++
drivers/spi/Kconfig | 9 ++
drivers/spi/Makefile | 1 +
drivers/spi/ath79_spi.c | 240 +++++++++++++++++++++++++++++
4 files changed, 269 insertions(+)
create mode 100644 doc/device-tree-bindings/spi/spi-ath79.txt
create mode 100644 drivers/spi/ath79_spi.c
diff --git a/doc/device-tree-bindings/spi/spi-ath79.txt b/doc/device-tree-bindings/spi/spi-ath79.txt
new file mode 100644
index 0000000..3fd9d67
--- /dev/null
+++ b/doc/device-tree-bindings/spi/spi-ath79.txt
@@ -0,0 +1,19 @@
+Binding for Qualcomm Atheros AR7xxx/AR9xxx SPI controller
+
+Required properties:
+- compatible: has to be "qca,<soc-type>-spi", "qca,ar7100-spi" as fallback.
+- reg: Base address and size of the controllers memory area
+- #address-cells: <1>, as required by generic SPI binding.
+- #size-cells: <0>, also as required by generic SPI binding.
+
+Child nodes as per the generic SPI binding.
+
+Example:
+
+ spi at 1f000000 {
+ compatible = "qca,ar9132-spi", "qca,ar7100-spi";
+ reg = <0x1f000000 0x10>;
+
+ #address-cells = <1>;
+ #size-cells = <0>;
+ };
diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
index 2cdb110..c6662b3 100644
--- a/drivers/spi/Kconfig
+++ b/drivers/spi/Kconfig
@@ -23,6 +23,15 @@ config ALTERA_SPI
IP core. Please find details on the "Embedded Peripherals IP
User Guide" of Altera.
+config ATH79_SPI
+ bool "Atheros SPI driver"
+ depends on ARCH_ATH79
+ help
+ Enable the Atheros ar7xxx/ar9xxx SoC SPI driver, it was used
+ to access SPI NOR flash and other SPI peripherals. This driver
+ uses driver model and requires a device tree binding to operate.
+ please refer to doc/device-tree-bindings/spi/spi-ath79.txt.
+
config CADENCE_QSPI
bool "Cadence QSPI driver"
help
diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile
index 3eca745..7fb2926 100644
--- a/drivers/spi/Makefile
+++ b/drivers/spi/Makefile
@@ -17,6 +17,7 @@ endif
obj-$(CONFIG_ALTERA_SPI) += altera_spi.o
obj-$(CONFIG_ARMADA100_SPI) += armada100_spi.o
+obj-$(CONFIG_ATH79_SPI) += ath79_spi.o
obj-$(CONFIG_ATMEL_DATAFLASH_SPI) += atmel_dataflash_spi.o
obj-$(CONFIG_ATMEL_SPI) += atmel_spi.o
obj-$(CONFIG_BFIN_SPI) += bfin_spi.o
diff --git a/drivers/spi/ath79_spi.c b/drivers/spi/ath79_spi.c
new file mode 100644
index 0000000..0c1022d
--- /dev/null
+++ b/drivers/spi/ath79_spi.c
@@ -0,0 +1,240 @@
+/*
+ * Copyright (C) 2015-2016 Wills Wang <wills.wang at live.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#include <common.h>
+#include <spi.h>
+#include <dm.h>
+#include <div64.h>
+#include <errno.h>
+#include <asm/io.h>
+#include <asm/addrspace.h>
+#include <asm/types.h>
+#include <dm/pinctrl.h>
+#include <mach/ar71xx_regs.h>
+
+/* CLOCK_DIVIDER = 3 (SPI clock = 200 / 8 ~ 25 MHz) */
+#define ATH79_SPI_CLK_DIV(x) (((x) >> 1) - 1)
+#define ATH79_SPI_RRW_DELAY_FACTOR 12000
+#define ATH79_SPI_MHZ (1000 * 1000)
+
+struct ath79_spi_priv {
+ void __iomem *regs;
+ u32 rrw_delay;
+};
+
+static void spi_cs_activate(struct udevice *dev)
+{
+ struct udevice *bus = dev_get_parent(dev);
+ struct ath79_spi_priv *priv = dev_get_priv(bus);
+
+ writel(AR71XX_SPI_FS_GPIO, priv->regs + AR71XX_SPI_REG_FS);
+ writel(AR71XX_SPI_IOC_CS_ALL, priv->regs + AR71XX_SPI_REG_IOC);
+}
+
+static void spi_cs_deactivate(struct udevice *dev)
+{
+ struct udevice *bus = dev_get_parent(dev);
+ struct ath79_spi_priv *priv = dev_get_priv(bus);
+
+ writel(AR71XX_SPI_IOC_CS_ALL, priv->regs + AR71XX_SPI_REG_IOC);
+ writel(0, priv->regs + AR71XX_SPI_REG_FS);
+}
+
+static int ath79_spi_claim_bus(struct udevice *dev)
+{
+ return 0;
+}
+
+static int ath79_spi_release_bus(struct udevice *dev)
+{
+ return 0;
+}
+
+static int ath79_spi_xfer(struct udevice *dev, unsigned int bitlen,
+ const void *dout, void *din, unsigned long flags)
+{
+ struct udevice *bus = dev_get_parent(dev);
+ struct ath79_spi_priv *priv = dev_get_priv(bus);
+ struct dm_spi_slave_platdata *slave = dev_get_parent_platdata(dev);
+ u8 *rx = din;
+ const u8 *tx = dout;
+ u8 curbyte, curbitlen, restbits;
+ u32 bytes = bitlen / 8;
+ u32 out, in;
+ u64 tick;
+
+ if (flags & SPI_XFER_BEGIN)
+ spi_cs_activate(dev);
+
+ restbits = (bitlen % 8);
+ if (restbits)
+ bytes++;
+
+ out = AR71XX_SPI_IOC_CS_ALL & ~(AR71XX_SPI_IOC_CS(slave->cs));
+ while (bytes > 0) {
+ bytes--;
+ curbyte = 0;
+ if (tx)
+ curbyte = *tx++;
+
+ if (restbits && !bytes) {
+ curbitlen = restbits;
+ curbyte <<= 8 - restbits;
+ } else {
+ curbitlen = 8;
+ }
+
+ for (curbyte <<= (8 - curbitlen); curbitlen; curbitlen--) {
+ if (curbyte & 0x80)
+ out |= AR71XX_SPI_IOC_DO;
+ else
+ out &= ~(AR71XX_SPI_IOC_DO);
+
+ writel(out, priv->regs + AR71XX_SPI_REG_IOC);
+
+ /* delay for low level */
+ if (priv->rrw_delay) {
+ tick = get_ticks() + priv->rrw_delay;
+ while (get_ticks() < tick)
+ /*NOP*/;
+ }
+
+ writel(out | AR71XX_SPI_IOC_CLK,
+ priv->regs + AR71XX_SPI_REG_IOC);
+
+ /* delay for high level */
+ if (priv->rrw_delay) {
+ tick = get_ticks() + priv->rrw_delay;
+ while (get_ticks() < tick)
+ /*NOP*/;
+ }
+
+ curbyte <<= 1;
+ }
+
+ if (!bytes)
+ writel(out, priv->regs + AR71XX_SPI_REG_IOC);
+
+ in = readl(priv->regs + AR71XX_SPI_REG_RDS);
+ if (rx) {
+ if (restbits && !bytes)
+ *rx++ = (in << (8 - restbits));
+ else
+ *rx++ = in;
+ }
+ }
+
+ if (flags & SPI_XFER_END)
+ spi_cs_deactivate(dev);
+
+ return 0;
+}
+
+
+static int ath79_spi_set_speed(struct udevice *bus, uint speed)
+{
+ struct ath79_spi_priv *priv = dev_get_priv(bus);
+ u32 val, div = 0;
+ u64 time;
+
+ if (speed)
+ div = get_bus_freq(0) / speed;
+
+ if (div > 63)
+ div = 63;
+
+ if (div < 5)
+ div = 5;
+
+ /* calculate delay */
+ time = get_tbclk();
+ do_div(time, speed / 2);
+ val = get_bus_freq(0) / ATH79_SPI_MHZ;
+ val = ATH79_SPI_RRW_DELAY_FACTOR / val;
+ if (time > val)
+ priv->rrw_delay = time - val + 1;
+ else
+ priv->rrw_delay = 0;
+
+ writel(AR71XX_SPI_FS_GPIO, priv->regs + AR71XX_SPI_REG_FS);
+ clrsetbits_be32(priv->regs + AR71XX_SPI_REG_CTRL,
+ AR71XX_SPI_CTRL_DIV_MASK,
+ ATH79_SPI_CLK_DIV(div));
+ writel(0, priv->regs + AR71XX_SPI_REG_FS);
+ return 0;
+}
+
+static int ath79_spi_set_mode(struct udevice *bus, uint mode)
+{
+ return 0;
+}
+
+static int ath79_spi_probe(struct udevice *bus)
+{
+ struct ath79_spi_priv *priv = dev_get_priv(bus);
+ struct udevice *pinctrl;
+ fdt_addr_t addr;
+ int ret;
+
+ ret = uclass_get_device(UCLASS_PINCTRL, 0, &pinctrl);
+ if (ret)
+ return ret;
+ ret = pinctrl_get_periph_id(pinctrl, bus);
+ if (ret < 0)
+ return ret;
+ ret = pinctrl_request(pinctrl, ret, 0);
+ if (ret < 0)
+ return ret;
+
+ addr = dev_get_addr(bus);
+ if (addr == FDT_ADDR_T_NONE)
+ return -EINVAL;
+
+ priv->regs = map_physmem(addr,
+ AR71XX_SPI_SIZE,
+ MAP_NOCACHE);
+
+ /* Init SPI Hardware, disable remap, set clock */
+ writel(AR71XX_SPI_FS_GPIO, priv->regs + AR71XX_SPI_REG_FS);
+ writel(AR71XX_SPI_CTRL_RD | ATH79_SPI_CLK_DIV(8),
+ priv->regs + AR71XX_SPI_REG_CTRL);
+ writel(0, priv->regs + AR71XX_SPI_REG_FS);
+
+ return 0;
+}
+
+static int ath79_cs_info(struct udevice *bus, uint cs,
+ struct spi_cs_info *info)
+{
+ /* Always allow activity on CS 0/1/2 */
+ if (cs >= 3)
+ return -ENODEV;
+
+ return 0;
+}
+
+static const struct dm_spi_ops ath79_spi_ops = {
+ .claim_bus = ath79_spi_claim_bus,
+ .release_bus = ath79_spi_release_bus,
+ .xfer = ath79_spi_xfer,
+ .set_speed = ath79_spi_set_speed,
+ .set_mode = ath79_spi_set_mode,
+ .cs_info = ath79_cs_info,
+};
+
+static const struct udevice_id ath79_spi_ids[] = {
+ { .compatible = "qca,ar7100-spi" },
+ {}
+};
+
+U_BOOT_DRIVER(ath79_spi) = {
+ .name = "ath79_spi",
+ .id = UCLASS_SPI,
+ .of_match = ath79_spi_ids,
+ .ops = &ath79_spi_ops,
+ .priv_auto_alloc_size = sizeof(struct ath79_spi_priv),
+ .probe = ath79_spi_probe,
+};
--
1.9.1
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