[U-Boot] [PATCH v6 1/4] dm: spi: add BCM63xx HSSPI driver
Álvaro Fernández Rojas
noltari at gmail.com
Sat Jan 20 01:13:38 UTC 2018
This driver is a simplified version of linux/drivers/spi/spi-bcm63xx-hsspi.c
Signed-off-by: Álvaro Fernández Rojas <noltari at gmail.com>
Reviewed-by: Simon Glass <sjg at chromium.org>
Reviewed-by: Daniel Schwierzeck <daniel.schwierzeck at gmail.com>
---
v6: no changes
v5: Introduce changes suggested by Jagan Teki:
- Rename SPI_PP_ macros.
- cs_activate instead of claim_cs.
- deactivate_cs instead of release_cs.
- Use wait_for_bit_be32 instead of infinite loop.
v4: no changes.
v3: Switch to CONFIG_BCM63XX_HSSPI and rebase on top of SPI v4.
v2: Introduce changes suggested by Simon Glass:
- Split bcm63xx_hsspi_xfer() into smaller functions.
- Check possible clock errors.
- Check possible reset errors.
- Switch to devfdt_get_addr_size_index().
- Use setbits32_be() for clock gate.
drivers/spi/Kconfig | 8 +
drivers/spi/Makefile | 1 +
drivers/spi/bcm63xx_hsspi.c | 414 ++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 423 insertions(+)
create mode 100644 drivers/spi/bcm63xx_hsspi.c
diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
index ebc71c2e42..28ddcf85a3 100644
--- a/drivers/spi/Kconfig
+++ b/drivers/spi/Kconfig
@@ -40,6 +40,14 @@ config ATMEL_SPI
many AT91 (ARM) chips. This driver can be used to access
the SPI Flash, such as AT25DF321.
+config BCM63XX_HSSPI
+ bool "BCM63XX HSSPI driver"
+ depends on ARCH_BMIPS
+ help
+ Enable the BCM6328 HSSPI driver. This driver can be used to
+ access the SPI NOR flash on platforms embedding this Broadcom
+ SPI core.
+
config BCM63XX_SPI
bool "BCM6348 SPI driver"
depends on ARCH_BMIPS
diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile
index 5770b3f7cc..4b6000fd9a 100644
--- a/drivers/spi/Makefile
+++ b/drivers/spi/Makefile
@@ -18,6 +18,7 @@ endif
obj-$(CONFIG_ALTERA_SPI) += altera_spi.o
obj-$(CONFIG_ATH79_SPI) += ath79_spi.o
obj-$(CONFIG_ATMEL_SPI) += atmel_spi.o
+obj-$(CONFIG_BCM63XX_HSSPI) += bcm63xx_hsspi.o
obj-$(CONFIG_BCM63XX_SPI) += bcm63xx_spi.o
obj-$(CONFIG_CADENCE_QSPI) += cadence_qspi.o cadence_qspi_apb.o
obj-$(CONFIG_CF_SPI) += cf_spi.o
diff --git a/drivers/spi/bcm63xx_hsspi.c b/drivers/spi/bcm63xx_hsspi.c
new file mode 100644
index 0000000000..3393166a1e
--- /dev/null
+++ b/drivers/spi/bcm63xx_hsspi.c
@@ -0,0 +1,414 @@
+/*
+ * Copyright (C) 2017 Álvaro Fernández Rojas <noltari at gmail.com>
+ *
+ * Derived from linux/drivers/spi/spi-bcm63xx-hsspi.c:
+ * Copyright (C) 2000-2010 Broadcom Corporation
+ * Copyright (C) 2012-2013 Jonas Gorski <jogo at openwrt.org>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#include <common.h>
+#include <clk.h>
+#include <dm.h>
+#include <spi.h>
+#include <reset.h>
+#include <wait_bit.h>
+#include <asm/io.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+#define HSSPI_PP 0
+
+#define SPI_MAX_SYNC_CLOCK 30000000
+
+/* SPI Control register */
+#define SPI_CTL_REG 0x000
+#define SPI_CTL_CS_POL_SHIFT 0
+#define SPI_CTL_CS_POL_MASK (0xff << SPI_CTL_CS_POL_SHIFT)
+#define SPI_CTL_CLK_GATE_SHIFT 16
+#define SPI_CTL_CLK_GATE_MASK (1 << SPI_CTL_CLK_GATE_SHIFT)
+#define SPI_CTL_CLK_POL_SHIFT 17
+#define SPI_CTL_CLK_POL_MASK (1 << SPI_CTL_CLK_POL_SHIFT)
+
+/* SPI Interrupts registers */
+#define SPI_IR_STAT_REG 0x008
+#define SPI_IR_ST_MASK_REG 0x00c
+#define SPI_IR_MASK_REG 0x010
+
+#define SPI_IR_CLEAR_ALL 0xff001f1f
+
+/* SPI Ping-Pong Command registers */
+#define SPI_CMD_REG (0x080 + (0x40 * (HSSPI_PP)) + 0x00)
+#define SPI_CMD_OP_SHIFT 0
+#define SPI_CMD_OP_START (0x1 << SPI_CMD_OP_SHIFT)
+#define SPI_CMD_PFL_SHIFT 8
+#define SPI_CMD_PFL_MASK (0x7 << SPI_CMD_PFL_SHIFT)
+#define SPI_CMD_SLAVE_SHIFT 12
+#define SPI_CMD_SLAVE_MASK (0x7 << SPI_CMD_SLAVE_SHIFT)
+
+/* SPI Ping-Pong Status registers */
+#define SPI_STAT_REG (0x080 + (0x40 * (HSSPI_PP)) + 0x04)
+#define SPI_STAT_SRCBUSY_SHIFT 1
+#define SPI_STAT_SRCBUSY_MASK (1 << SPI_STAT_SRCBUSY_SHIFT)
+
+/* SPI Profile Clock registers */
+#define SPI_PFL_CLK_REG(x) (0x100 + (0x20 * (x)) + 0x00)
+#define SPI_PFL_CLK_FREQ_SHIFT 0
+#define SPI_PFL_CLK_FREQ_MASK (0x3fff << SPI_PFL_CLK_FREQ_SHIFT)
+#define SPI_PFL_CLK_RSTLOOP_SHIFT 15
+#define SPI_PFL_CLK_RSTLOOP_MASK (1 << SPI_PFL_CLK_RSTLOOP_SHIFT)
+
+/* SPI Profile Signal registers */
+#define SPI_PFL_SIG_REG(x) (0x100 + (0x20 * (x)) + 0x04)
+#define SPI_PFL_SIG_LATCHRIS_SHIFT 12
+#define SPI_PFL_SIG_LATCHRIS_MASK (1 << SPI_PFL_SIG_LATCHRIS_SHIFT)
+#define SPI_PFL_SIG_LAUNCHRIS_SHIFT 13
+#define SPI_PFL_SIG_LAUNCHRIS_MASK (1 << SPI_PFL_SIG_LAUNCHRIS_SHIFT)
+#define SPI_PFL_SIG_ASYNCIN_SHIFT 16
+#define SPI_PFL_SIG_ASYNCIN_MASK (1 << SPI_PFL_SIG_ASYNCIN_SHIFT)
+
+/* SPI Profile Mode registers */
+#define SPI_PFL_MODE_REG(x) (0x100 + (0x20 * (x)) + 0x08)
+#define SPI_PFL_MODE_FILL_SHIFT 0
+#define SPI_PFL_MODE_FILL_MASK (0xff << SPI_PFL_MODE_FILL_SHIFT)
+#define SPI_PFL_MODE_MDRDSZ_SHIFT 16
+#define SPI_PFL_MODE_MDRDSZ_MASK (1 << SPI_PFL_MODE_MDRDSZ_SHIFT)
+#define SPI_PFL_MODE_MDWRSZ_SHIFT 18
+#define SPI_PFL_MODE_MDWRSZ_MASK (1 << SPI_PFL_MODE_MDWRSZ_SHIFT)
+#define SPI_PFL_MODE_3WIRE_SHIFT 20
+#define SPI_PFL_MODE_3WIRE_MASK (1 << SPI_PFL_MODE_3WIRE_SHIFT)
+
+/* SPI Ping-Pong FIFO registers */
+#define HSSPI_FIFO_SIZE 0x200
+#define HSSPI_FIFO_BASE (0x200 + \
+ (HSSPI_FIFO_SIZE * HSSPI_PP))
+
+/* SPI Ping-Pong FIFO OP register */
+#define HSSPI_FIFO_OP_SIZE 0x2
+#define HSSPI_FIFO_OP_REG (HSSPI_FIFO_BASE + 0x00)
+#define HSSPI_FIFO_OP_BYTES_SHIFT 0
+#define HSSPI_FIFO_OP_BYTES_MASK (0x3ff << HSSPI_FIFO_OP_BYTES_SHIFT)
+#define HSSPI_FIFO_OP_MBIT_SHIFT 11
+#define HSSPI_FIFO_OP_MBIT_MASK (1 << HSSPI_FIFO_OP_MBIT_SHIFT)
+#define HSSPI_FIFO_OP_CODE_SHIFT 13
+#define HSSPI_FIFO_OP_READ_WRITE (1 << HSSPI_FIFO_OP_CODE_SHIFT)
+#define HSSPI_FIFO_OP_CODE_W (2 << HSSPI_FIFO_OP_CODE_SHIFT)
+#define HSSPI_FIFO_OP_CODE_R (3 << HSSPI_FIFO_OP_CODE_SHIFT)
+
+struct bcm63xx_hsspi_priv {
+ void __iomem *regs;
+ ulong clk_rate;
+ uint8_t num_cs;
+ uint8_t cs_pols;
+ uint speed;
+};
+
+static int bcm63xx_hsspi_cs_info(struct udevice *bus, uint cs,
+ struct spi_cs_info *info)
+{
+ struct bcm63xx_hsspi_priv *priv = dev_get_priv(bus);
+
+ if (cs >= priv->num_cs) {
+ printf("no cs %u\n", cs);
+ return -ENODEV;
+ }
+
+ return 0;
+}
+
+static int bcm63xx_hsspi_set_mode(struct udevice *bus, uint mode)
+{
+ struct bcm63xx_hsspi_priv *priv = dev_get_priv(bus);
+
+ /* clock polarity */
+ if (mode & SPI_CPOL)
+ setbits_be32(priv->regs + SPI_CTL_REG, SPI_CTL_CLK_POL_MASK);
+ else
+ clrbits_be32(priv->regs + SPI_CTL_REG, SPI_CTL_CLK_POL_MASK);
+
+ return 0;
+}
+
+static int bcm63xx_hsspi_set_speed(struct udevice *bus, uint speed)
+{
+ struct bcm63xx_hsspi_priv *priv = dev_get_priv(bus);
+
+ priv->speed = speed;
+
+ return 0;
+}
+
+static void bcm63xx_hsspi_activate_cs(struct bcm63xx_hsspi_priv *priv,
+ struct dm_spi_slave_platdata *plat)
+{
+ uint32_t clr, set;
+
+ /* profile clock */
+ set = DIV_ROUND_UP(priv->clk_rate, priv->speed);
+ set = DIV_ROUND_UP(2048, set);
+ set &= SPI_PFL_CLK_FREQ_MASK;
+ set |= SPI_PFL_CLK_RSTLOOP_MASK;
+ writel_be(set, priv->regs + SPI_PFL_CLK_REG(plat->cs));
+
+ /* profile signal */
+ set = 0;
+ clr = SPI_PFL_SIG_LAUNCHRIS_MASK |
+ SPI_PFL_SIG_LATCHRIS_MASK |
+ SPI_PFL_SIG_ASYNCIN_MASK;
+
+ /* latch/launch config */
+ if (plat->mode & SPI_CPHA)
+ set |= SPI_PFL_SIG_LAUNCHRIS_MASK;
+ else
+ set |= SPI_PFL_SIG_LATCHRIS_MASK;
+
+ /* async clk */
+ if (priv->speed > SPI_MAX_SYNC_CLOCK)
+ set |= SPI_PFL_SIG_ASYNCIN_MASK;
+
+ clrsetbits_be32(priv->regs + SPI_PFL_SIG_REG(plat->cs), clr, set);
+
+ /* global control */
+ set = 0;
+ clr = 0;
+
+ /* invert cs polarity */
+ if (priv->cs_pols & BIT(plat->cs))
+ clr |= BIT(plat->cs);
+ else
+ set |= BIT(plat->cs);
+
+ /* invert dummy cs polarity */
+ if (priv->cs_pols & BIT(!plat->cs))
+ clr |= BIT(!plat->cs);
+ else
+ set |= BIT(!plat->cs);
+
+ clrsetbits_be32(priv->regs + SPI_CTL_REG, clr, set);
+}
+
+static void bcm63xx_hsspi_deactivate_cs(struct bcm63xx_hsspi_priv *priv)
+{
+ /* restore cs polarities */
+ clrsetbits_be32(priv->regs + SPI_CTL_REG, SPI_CTL_CS_POL_MASK,
+ priv->cs_pols);
+}
+
+/*
+ * BCM63xx HSSPI driver doesn't allow keeping CS active between transfers
+ * because they are controlled by HW.
+ * However, it provides a mechanism to prepend write transfers prior to read
+ * transfers (with a maximum prepend of 15 bytes), which is usually enough for
+ * SPI-connected flashes since reading requires prepending a write transfer of
+ * 5 bytes. On the other hand it also provides a way to invert each CS
+ * polarity, not only between transfers like the older BCM63xx SPI driver, but
+ * also the rest of the time.
+ *
+ * Instead of using the prepend mechanism, this implementation inverts the
+ * polarity of both the desired CS and another dummy CS when the bus is
+ * claimed. This way, the dummy CS is restored to its inactive value when
+ * transfers are issued and the desired CS is preserved in its active value
+ * all the time. This hack is also used in the upstream linux driver and
+ * allows keeping CS active between trasnfers even if the HW doesn't give
+ * this possibility.
+ */
+static int bcm63xx_hsspi_xfer(struct udevice *dev, unsigned int bitlen,
+ const void *dout, void *din, unsigned long flags)
+{
+ struct bcm63xx_hsspi_priv *priv = dev_get_priv(dev->parent);
+ struct dm_spi_slave_platdata *plat = dev_get_parent_platdata(dev);
+ size_t data_bytes = bitlen / 8;
+ size_t step_size = HSSPI_FIFO_SIZE;
+ uint16_t opcode = 0;
+ uint32_t val;
+ const uint8_t *tx = dout;
+ uint8_t *rx = din;
+
+ if (flags & SPI_XFER_BEGIN)
+ bcm63xx_hsspi_activate_cs(priv, plat);
+
+ /* fifo operation */
+ if (tx && rx)
+ opcode = HSSPI_FIFO_OP_READ_WRITE;
+ else if (rx)
+ opcode = HSSPI_FIFO_OP_CODE_R;
+ else if (tx)
+ opcode = HSSPI_FIFO_OP_CODE_W;
+
+ if (opcode != HSSPI_FIFO_OP_CODE_R)
+ step_size -= HSSPI_FIFO_OP_SIZE;
+
+ /* dual mode */
+ if ((opcode == HSSPI_FIFO_OP_CODE_R && plat->mode == SPI_RX_DUAL) ||
+ (opcode == HSSPI_FIFO_OP_CODE_W && plat->mode == SPI_TX_DUAL))
+ opcode |= HSSPI_FIFO_OP_MBIT_MASK;
+
+ /* profile mode */
+ val = SPI_PFL_MODE_FILL_MASK |
+ SPI_PFL_MODE_MDRDSZ_MASK |
+ SPI_PFL_MODE_MDWRSZ_MASK;
+ if (plat->mode & SPI_3WIRE)
+ val |= SPI_PFL_MODE_3WIRE_MASK;
+ writel_be(val, priv->regs + SPI_PFL_MODE_REG(plat->cs));
+
+ /* transfer loop */
+ while (data_bytes > 0) {
+ size_t curr_step = min(step_size, data_bytes);
+ int ret;
+
+ /* copy tx data */
+ if (tx) {
+ memcpy_toio(priv->regs + HSSPI_FIFO_BASE +
+ HSSPI_FIFO_OP_SIZE, tx, curr_step);
+ tx += curr_step;
+ }
+
+ /* set fifo operation */
+ writew_be(opcode | (curr_step & HSSPI_FIFO_OP_BYTES_MASK),
+ priv->regs + HSSPI_FIFO_OP_REG);
+
+ /* issue the transfer */
+ val = SPI_CMD_OP_START;
+ val |= (plat->cs << SPI_CMD_PFL_SHIFT) &
+ SPI_CMD_PFL_MASK;
+ val |= (!plat->cs << SPI_CMD_SLAVE_SHIFT) &
+ SPI_CMD_SLAVE_MASK;
+ writel_be(val, priv->regs + SPI_CMD_REG);
+
+ /* wait for completion */
+ ret = wait_for_bit_be32(priv->regs + SPI_STAT_REG,
+ SPI_STAT_SRCBUSY_MASK, false,
+ 1000, false);
+ if (ret) {
+ printf("interrupt timeout\n");
+ return ret;
+ }
+
+ /* copy rx data */
+ if (rx) {
+ memcpy_fromio(rx, priv->regs + HSSPI_FIFO_BASE,
+ curr_step);
+ rx += curr_step;
+ }
+
+ data_bytes -= curr_step;
+ }
+
+ if (flags & SPI_XFER_END)
+ bcm63xx_hsspi_deactivate_cs(priv);
+
+ return 0;
+}
+
+static const struct dm_spi_ops bcm63xx_hsspi_ops = {
+ .cs_info = bcm63xx_hsspi_cs_info,
+ .set_mode = bcm63xx_hsspi_set_mode,
+ .set_speed = bcm63xx_hsspi_set_speed,
+ .xfer = bcm63xx_hsspi_xfer,
+};
+
+static const struct udevice_id bcm63xx_hsspi_ids[] = {
+ { .compatible = "brcm,bcm6328-hsspi", },
+ { /* sentinel */ }
+};
+
+static int bcm63xx_hsspi_child_pre_probe(struct udevice *dev)
+{
+ struct bcm63xx_hsspi_priv *priv = dev_get_priv(dev->parent);
+ struct dm_spi_slave_platdata *plat = dev_get_parent_platdata(dev);
+
+ /* check cs */
+ if (plat->cs >= priv->num_cs) {
+ printf("no cs %u\n", plat->cs);
+ return -ENODEV;
+ }
+
+ /* cs polarity */
+ if (plat->mode & SPI_CS_HIGH)
+ priv->cs_pols |= BIT(plat->cs);
+ else
+ priv->cs_pols &= ~BIT(plat->cs);
+
+ return 0;
+}
+
+static int bcm63xx_hsspi_probe(struct udevice *dev)
+{
+ struct bcm63xx_hsspi_priv *priv = dev_get_priv(dev);
+ struct reset_ctl rst_ctl;
+ struct clk clk;
+ fdt_addr_t addr;
+ fdt_size_t size;
+ int ret;
+
+ addr = devfdt_get_addr_size_index(dev, 0, &size);
+ if (addr == FDT_ADDR_T_NONE)
+ return -EINVAL;
+
+ priv->regs = ioremap(addr, size);
+ priv->num_cs = fdtdec_get_uint(gd->fdt_blob, dev_of_offset(dev),
+ "num-cs", 8);
+
+ /* enable clock */
+ ret = clk_get_by_name(dev, "hsspi", &clk);
+ if (ret < 0)
+ return ret;
+
+ ret = clk_enable(&clk);
+ if (ret < 0)
+ return ret;
+
+ ret = clk_free(&clk);
+ if (ret < 0)
+ return ret;
+
+ /* get clock rate */
+ ret = clk_get_by_name(dev, "pll", &clk);
+ if (ret < 0)
+ return ret;
+
+ priv->clk_rate = clk_get_rate(&clk);
+
+ ret = clk_free(&clk);
+ if (ret < 0)
+ return ret;
+
+ /* perform reset */
+ ret = reset_get_by_index(dev, 0, &rst_ctl);
+ if (ret < 0)
+ return ret;
+
+ ret = reset_deassert(&rst_ctl);
+ if (ret < 0)
+ return ret;
+
+ ret = reset_free(&rst_ctl);
+ if (ret < 0)
+ return ret;
+
+ /* initialize hardware */
+ writel_be(0, priv->regs + SPI_IR_MASK_REG);
+
+ /* clear pending interrupts */
+ writel_be(SPI_IR_CLEAR_ALL, priv->regs + SPI_IR_STAT_REG);
+
+ /* enable clk gate */
+ setbits_be32(priv->regs + SPI_CTL_REG, SPI_CTL_CLK_GATE_MASK);
+
+ /* read default cs polarities */
+ priv->cs_pols = readl_be(priv->regs + SPI_CTL_REG) &
+ SPI_CTL_CS_POL_MASK;
+
+ return 0;
+}
+
+U_BOOT_DRIVER(bcm63xx_hsspi) = {
+ .name = "bcm63xx_hsspi",
+ .id = UCLASS_SPI,
+ .of_match = bcm63xx_hsspi_ids,
+ .ops = &bcm63xx_hsspi_ops,
+ .priv_auto_alloc_size = sizeof(struct bcm63xx_hsspi_priv),
+ .child_pre_probe = bcm63xx_hsspi_child_pre_probe,
+ .probe = bcm63xx_hsspi_probe,
+};
--
2.11.0
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