]> git.sur5r.net Git - u-boot/commitdiff
rockchip: Add SPI driver
authorSimon Glass <sjg@chromium.org>
Wed, 2 Sep 2015 01:19:37 +0000 (19:19 -0600)
committerSimon Glass <sjg@chromium.org>
Thu, 3 Sep 2015 03:28:24 +0000 (21:28 -0600)
Add a SPI driver for the Rockchip RK3288, using driver model. It should work
for other Rockchip SoCs also.

Signed-off-by: Simon Glass <sjg@chromium.org>
arch/arm/include/asm/arch-rockchip/clock.h
drivers/spi/Kconfig
drivers/spi/Makefile
drivers/spi/rk_spi.c [new file with mode: 0644]
drivers/spi/rk_spi.h [new file with mode: 0644]

index 2e5ba86a633895c826e5c8e03fc1669c704dd589..8a0376c501ed117c1b6759b8a46f784d023da649 100644 (file)
@@ -35,6 +35,26 @@ static inline int rk_pll_id(enum rk_clk_id clk_id)
        return clk_id - 1;
 }
 
+/**
+ * clk_get_divisor() - Calculate the required clock divisior
+ *
+ * Given an input rate and a required output_rate, calculate the Rockchip
+ * divisor needed to achieve this.
+ *
+ * @input_rate:                Input clock rate in Hz
+ * @output_rate:       Output clock rate in Hz
+ * @return divisor register value to use
+ */
+static inline u32 clk_get_divisor(ulong input_rate, uint output_rate)
+{
+       uint clk_div;
+
+       clk_div = input_rate / output_rate;
+       clk_div = (clk_div + 1) & 0xfffe;
+
+       return clk_div;
+}
+
 /**
  * rockchip_get_cru() - get a pointer to the clock/reset unit registers
  *
index c84a7b74d6cad193ad209f27fc8ed0b8f89fa1c3..8e04fce6f2ab10075f59ac53b5ec1c077b515905 100644 (file)
@@ -58,6 +58,14 @@ config ICH_SPI
          access the SPI NOR flash on platforms embedding this Intel
          ICH IP core.
 
+config ROCKCHIP_SPI
+       bool "Rockchip SPI driver"
+       help
+         Enable the Rockchip SPI driver, used to access SPI NOR flash and
+         other SPI peripherals (such as the Chrome OS EC) on Rockchip SoCs.
+         This uses driver model and requires a device tree binding to
+         operate.
+
 config SANDBOX_SPI
        bool "Sandbox SPI driver"
        depends on SANDBOX && DM
index ee88aa162bc1405a361f1adcc15dcaf29d1f082b..de241be15a7660dcfd93401aeb7688f95fa9490c 100644 (file)
@@ -39,6 +39,7 @@ obj-$(CONFIG_MPC8XXX_SPI) += mpc8xxx_spi.o
 obj-$(CONFIG_MXC_SPI) += mxc_spi.o
 obj-$(CONFIG_MXS_SPI) += mxs_spi.o
 obj-$(CONFIG_OMAP3_SPI) += omap3_spi.o
+obj-$(CONFIG_ROCKCHIP_SPI) += rk_spi.o
 obj-$(CONFIG_SANDBOX_SPI) += sandbox_spi.o
 obj-$(CONFIG_SH_SPI) += sh_spi.o
 obj-$(CONFIG_SH_QSPI) += sh_qspi.o
diff --git a/drivers/spi/rk_spi.c b/drivers/spi/rk_spi.c
new file mode 100644 (file)
index 0000000..5e0c6ad
--- /dev/null
@@ -0,0 +1,374 @@
+/*
+ * spi driver for rockchip
+ *
+ * (C) Copyright 2015 Google, Inc
+ *
+ * (C) Copyright 2008-2013 Rockchip Electronics
+ * Peter, Software Engineering, <superpeter.cai@gmail.com>.
+ *
+ * SPDX-License-Identifier:     GPL-2.0+
+ */
+
+#include <common.h>
+#include <clk.h>
+#include <dm.h>
+#include <errno.h>
+#include <spi.h>
+#include <asm/errno.h>
+#include <asm/io.h>
+#include <asm/arch/clock.h>
+#include <asm/arch/periph.h>
+#include <dm/pinctrl.h>
+#include "rk_spi.h"
+
+DECLARE_GLOBAL_DATA_PTR;
+
+/* Change to 1 to output registers at the start of each transaction */
+#define DEBUG_RK_SPI   0
+
+struct rockchip_spi_platdata {
+       enum periph_id periph_id;
+       struct udevice *pinctrl;
+       s32 frequency;          /* Default clock frequency, -1 for none */
+       fdt_addr_t base;
+       uint deactivate_delay_us;       /* Delay to wait after deactivate */
+};
+
+struct rockchip_spi_priv {
+       struct rockchip_spi *regs;
+       struct udevice *clk_gpll;
+       unsigned int max_freq;
+       unsigned int mode;
+       enum periph_id periph_id;       /* Peripheral ID for this device */
+       ulong last_transaction_us;      /* Time of last transaction end */
+       u8 bits_per_word;               /* max 16 bits per word */
+       u8 n_bytes;
+       unsigned int speed_hz;
+       unsigned int tmode;
+       uint input_rate;
+};
+
+#define SPI_FIFO_DEPTH         32
+
+static void rkspi_dump_regs(struct rockchip_spi *regs)
+{
+       debug("ctrl0: \t\t0x%08x\n", readl(&regs->ctrlr0));
+       debug("ctrl1: \t\t0x%08x\n", readl(&regs->ctrlr1));
+       debug("ssienr: \t\t0x%08x\n", readl(&regs->enr));
+       debug("ser: \t\t0x%08x\n", readl(&regs->ser));
+       debug("baudr: \t\t0x%08x\n", readl(&regs->baudr));
+       debug("txftlr: \t\t0x%08x\n", readl(&regs->txftlr));
+       debug("rxftlr: \t\t0x%08x\n", readl(&regs->rxftlr));
+       debug("txflr: \t\t0x%08x\n", readl(&regs->txflr));
+       debug("rxflr: \t\t0x%08x\n", readl(&regs->rxflr));
+       debug("sr: \t\t0x%08x\n", readl(&regs->sr));
+       debug("imr: \t\t0x%08x\n", readl(&regs->imr));
+       debug("isr: \t\t0x%08x\n", readl(&regs->isr));
+       debug("dmacr: \t\t0x%08x\n", readl(&regs->dmacr));
+       debug("dmatdlr: \t0x%08x\n", readl(&regs->dmatdlr));
+       debug("dmardlr: \t0x%08x\n", readl(&regs->dmardlr));
+}
+
+static void rkspi_enable_chip(struct rockchip_spi *regs, bool enable)
+{
+       writel(enable ? 1 : 0, &regs->enr);
+}
+
+static void rkspi_set_clk(struct rockchip_spi_priv *priv, uint speed)
+{
+       uint clk_div;
+
+       clk_div = clk_get_divisor(priv->input_rate, speed);
+       debug("spi speed %u, div %u\n", speed, clk_div);
+
+       writel(clk_div, &priv->regs->baudr);
+}
+
+static int rkspi_wait_till_not_busy(struct rockchip_spi *regs)
+{
+       unsigned long start;
+
+       start = get_timer(0);
+       while (readl(&regs->sr) & SR_BUSY) {
+               if (get_timer(start) > ROCKCHIP_SPI_TIMEOUT_MS) {
+                       debug("RK SPI: Status keeps busy for 1000us after a read/write!\n");
+                       return -ETIMEDOUT;
+               }
+       }
+
+       return 0;
+}
+
+static void spi_cs_activate(struct rockchip_spi *regs, uint cs)
+{
+       debug("activate cs%u\n", cs);
+       writel(1 << cs, &regs->ser);
+}
+
+static void spi_cs_deactivate(struct rockchip_spi *regs, uint cs)
+{
+       debug("deactivate cs%u\n", cs);
+       writel(0, &regs->ser);
+}
+
+static int rockchip_spi_ofdata_to_platdata(struct udevice *bus)
+{
+       struct rockchip_spi_platdata *plat = bus->platdata;
+       const void *blob = gd->fdt_blob;
+       int node = bus->of_offset;
+       int ret;
+
+       plat->base = dev_get_addr(bus);
+       ret = uclass_get_device(UCLASS_PINCTRL, 0, &plat->pinctrl);
+       if (ret)
+               return ret;
+       ret = pinctrl_get_periph_id(plat->pinctrl, bus);
+
+       if (ret < 0) {
+               debug("%s: Could not get peripheral ID for %s: %d\n", __func__,
+                     bus->name, ret);
+               return -FDT_ERR_NOTFOUND;
+       }
+       plat->periph_id = ret;
+
+       plat->frequency = fdtdec_get_int(blob, node, "spi-max-frequency",
+                                       50000000);
+       plat->deactivate_delay_us = fdtdec_get_int(blob, node,
+                                       "spi-deactivate-delay", 0);
+       debug("%s: base=%x, periph_id=%d, max-frequency=%d, deactivate_delay=%d\n",
+             __func__, plat->base, plat->periph_id, plat->frequency,
+             plat->deactivate_delay_us);
+
+       return 0;
+}
+
+static int rockchip_spi_probe(struct udevice *bus)
+{
+       struct rockchip_spi_platdata *plat = dev_get_platdata(bus);
+       struct rockchip_spi_priv *priv = dev_get_priv(bus);
+       int ret;
+
+       debug("%s: probe\n", __func__);
+       priv->regs = (struct rockchip_spi *)plat->base;
+
+       priv->last_transaction_us = timer_get_us();
+       priv->max_freq = plat->frequency;
+       priv->periph_id = plat->periph_id;
+       ret = uclass_get_device(UCLASS_CLK, CLK_GENERAL, &priv->clk_gpll);
+       if (ret) {
+               debug("%s: Failed to find CLK_GENERAL: %d\n", __func__, ret);
+               return ret;
+       }
+
+       /*
+        * Use 99 MHz as our clock since it divides nicely into 594 MHz which
+        * is the assumed speed for CLK_GENERAL.
+        */
+       ret = clk_set_periph_rate(priv->clk_gpll, plat->periph_id, 99000000);
+       if (ret < 0) {
+               debug("%s: Failed to set clock: %d\n", __func__, ret);
+               return ret;
+       }
+       priv->input_rate = ret;
+       debug("%s: rate = %u\n", __func__, priv->input_rate);
+       priv->bits_per_word = 8;
+       priv->tmode = TMOD_TR; /* Tx & Rx */
+
+       return 0;
+}
+
+static int rockchip_spi_claim_bus(struct udevice *dev)
+{
+       struct udevice *bus = dev->parent;
+       struct rockchip_spi_platdata *plat = dev_get_platdata(bus);
+       struct rockchip_spi_priv *priv = dev_get_priv(bus);
+       struct rockchip_spi *regs = priv->regs;
+       struct dm_spi_slave_platdata *slave_plat = dev_get_parent_platdata(dev);
+       u8 spi_dfs, spi_tf;
+       uint ctrlr0;
+       int ret;
+
+       /* Disable the SPI hardware */
+       rkspi_enable_chip(regs, 0);
+
+       switch (priv->bits_per_word) {
+       case 8:
+               priv->n_bytes = 1;
+               spi_dfs = DFS_8BIT;
+               spi_tf = HALF_WORD_OFF;
+               break;
+       case 16:
+               priv->n_bytes = 2;
+               spi_dfs = DFS_16BIT;
+               spi_tf = HALF_WORD_ON;
+               break;
+       default:
+               debug("%s: unsupported bits: %dbits\n", __func__,
+                     priv->bits_per_word);
+               return -EPROTONOSUPPORT;
+       }
+
+       rkspi_set_clk(priv, priv->speed_hz);
+
+       /* Operation Mode */
+       ctrlr0 = OMOD_MASTER << OMOD_SHIFT;
+
+       /* Data Frame Size */
+       ctrlr0 |= spi_dfs & DFS_MASK << DFS_SHIFT;
+
+       /* set SPI mode 0..3 */
+       if (priv->mode & SPI_CPOL)
+               ctrlr0 |= SCOL_HIGH << SCOL_SHIFT;
+       if (priv->mode & SPI_CPHA)
+               ctrlr0 |= SCPH_TOGSTA << SCPH_SHIFT;
+
+       /* Chip Select Mode */
+       ctrlr0 |= CSM_KEEP << CSM_SHIFT;
+
+       /* SSN to Sclk_out delay */
+       ctrlr0 |= SSN_DELAY_ONE << SSN_DELAY_SHIFT;
+
+       /* Serial Endian Mode */
+       ctrlr0 |= SEM_LITTLE << SEM_SHIFT;
+
+       /* First Bit Mode */
+       ctrlr0 |= FBM_MSB << FBM_SHIFT;
+
+       /* Byte and Halfword Transform */
+       ctrlr0 |= (spi_tf & HALF_WORD_MASK) << HALF_WORD_TX_SHIFT;
+
+       /* Rxd Sample Delay */
+       ctrlr0 |= 0 << RXDSD_SHIFT;
+
+       /* Frame Format */
+       ctrlr0 |= FRF_SPI << FRF_SHIFT;
+
+       /* Tx and Rx mode */
+       ctrlr0 |= (priv->tmode & TMOD_MASK) << TMOD_SHIFT;
+
+       writel(ctrlr0, &regs->ctrlr0);
+
+       ret = pinctrl_request(plat->pinctrl, priv->periph_id, slave_plat->cs);
+       if (ret) {
+               debug("%s: Cannot request pinctrl: %d\n", __func__, ret);
+               return ret;
+       }
+
+       return 0;
+}
+
+static int rockchip_spi_release_bus(struct udevice *dev)
+{
+       return 0;
+}
+
+static int rockchip_spi_xfer(struct udevice *dev, unsigned int bitlen,
+                          const void *dout, void *din, unsigned long flags)
+{
+       struct udevice *bus = dev->parent;
+       struct rockchip_spi_priv *priv = dev_get_priv(bus);
+       struct rockchip_spi *regs = priv->regs;
+       struct dm_spi_slave_platdata *slave_plat = dev_get_parent_platdata(dev);
+       int len = bitlen >> 3;
+       const u8 *out = dout;
+       u8 *in = din;
+       int toread, towrite;
+       int ret;
+
+       debug("%s: dout=%p, din=%p, len=%x, flags=%lx\n", __func__, dout, din,
+             len, flags);
+       if (DEBUG_RK_SPI)
+               rkspi_dump_regs(regs);
+
+       /* Assert CS before transfer */
+       if (flags & SPI_XFER_BEGIN)
+               spi_cs_activate(regs, slave_plat->cs);
+
+       while (len > 0) {
+               int todo = min(len, 0xffff);
+
+               rkspi_enable_chip(regs, true);
+               writel(todo - 1, &regs->ctrlr1);
+               rkspi_enable_chip(regs, true);
+
+               toread = todo;
+               towrite = todo;
+               while (toread || towrite) {
+                       u32 status = readl(&regs->sr);
+
+                       if (towrite && !(status & SR_TF_FULL)) {
+                               writel(out ? *out++ : 0, regs->txdr);
+                               towrite--;
+                       }
+                       if (toread && !(status & SR_RF_EMPT)) {
+                               u32 byte = readl(regs->rxdr);
+
+                               if (in)
+                                       *in++ = byte;
+                               toread--;
+                       }
+               }
+               ret = rkspi_wait_till_not_busy(regs);
+               if (ret)
+                       break;
+               len -= todo;
+       }
+
+       /* Deassert CS after transfer */
+       if (flags & SPI_XFER_END)
+               spi_cs_deactivate(regs, slave_plat->cs);
+
+       rkspi_enable_chip(regs, false);
+
+       return ret;
+}
+
+static int rockchip_spi_set_speed(struct udevice *bus, uint speed)
+{
+       struct rockchip_spi_priv *priv = dev_get_priv(bus);
+
+       if (speed > ROCKCHIP_SPI_MAX_RATE)
+               return -EINVAL;
+       if (speed > priv->max_freq)
+               speed = priv->max_freq;
+       priv->speed_hz = speed;
+
+       return 0;
+}
+
+static int rockchip_spi_set_mode(struct udevice *bus, uint mode)
+{
+       struct rockchip_spi_priv *priv = dev_get_priv(bus);
+
+       priv->mode = mode;
+
+       return 0;
+}
+
+static const struct dm_spi_ops rockchip_spi_ops = {
+       .claim_bus      = rockchip_spi_claim_bus,
+       .release_bus    = rockchip_spi_release_bus,
+       .xfer           = rockchip_spi_xfer,
+       .set_speed      = rockchip_spi_set_speed,
+       .set_mode       = rockchip_spi_set_mode,
+       /*
+        * cs_info is not needed, since we require all chip selects to be
+        * in the device tree explicitly
+        */
+};
+
+static const struct udevice_id rockchip_spi_ids[] = {
+       { .compatible = "rockchip,rk3288-spi" },
+       { }
+};
+
+U_BOOT_DRIVER(rockchip_spi) = {
+       .name   = "rockchip_spi",
+       .id     = UCLASS_SPI,
+       .of_match = rockchip_spi_ids,
+       .ops    = &rockchip_spi_ops,
+       .ofdata_to_platdata = rockchip_spi_ofdata_to_platdata,
+       .platdata_auto_alloc_size = sizeof(struct rockchip_spi_platdata),
+       .priv_auto_alloc_size = sizeof(struct rockchip_spi_priv),
+       .probe  = rockchip_spi_probe,
+};
diff --git a/drivers/spi/rk_spi.h b/drivers/spi/rk_spi.h
new file mode 100644 (file)
index 0000000..f1ac812
--- /dev/null
@@ -0,0 +1,124 @@
+/*
+ * SPI driver for rockchip
+ *
+ * (C) Copyright 2015 Google, Inc
+ *
+ * (C) Copyright 2008-2013 Rockchip Electronics
+ * Peter, Software Engineering, <superpeter.cai@gmail.com>.
+ *
+ * SPDX-License-Identifier:     GPL-2.0+
+ */
+
+#ifndef __RK_SPI_H
+#define __RK_SPI_H
+
+struct rockchip_spi {
+       u32 ctrlr0;
+       u32 ctrlr1;
+       u32 enr;
+       u32 ser;
+       u32 baudr;
+       u32 txftlr;
+       u32 rxftlr;
+       u32 txflr;
+       u32 rxflr;
+       u32 sr;
+       u32 ipr;
+       u32 imr;
+       u32 isr;
+       u32 risr;
+       u32 icr;
+       u32 dmacr;
+       u32 dmatdlr;
+       u32 dmardlr;            /* 0x44 */
+       u32 reserved[0xef];
+       u32 txdr[0x100];        /* 0x400 */
+       u32 rxdr[0x100];        /* 0x800 */
+};
+
+/* CTRLR0 */
+enum {
+       DFS_SHIFT       = 0,    /* Data Frame Size */
+       DFS_MASK        = 3,
+       DFS_4BIT        = 0,
+       DFS_8BIT,
+       DFS_16BIT,
+       DFS_RESV,
+
+       CFS_SHIFT       = 2,    /* Control Frame Size */
+       CFS_MASK        = 0xf,
+
+       SCPH_SHIFT      = 6,    /* Serial Clock Phase */
+       SCPH_MASK       = 1,
+       SCPH_TOGMID     = 0,    /* SCLK toggles in middle of first data bit */
+       SCPH_TOGSTA,            /* SCLK toggles at start of first data bit */
+
+       SCOL_SHIFT      = 7,    /* Serial Clock Polarity */
+       SCOL_MASK       = 1,
+       SCOL_LOW        = 0,    /* Inactive state of serial clock is low */
+       SCOL_HIGH,              /* Inactive state of serial clock is high */
+
+       CSM_SHIFT       = 8,    /* Chip Select Mode */
+       CSM_MASK        = 0x3,
+       CSM_KEEP        = 0,    /* ss_n stays low after each frame  */
+       CSM_HALF,               /* ss_n high for half sclk_out cycles */
+       CSM_ONE,                /* ss_n high for one sclk_out cycle */
+       CSM_RESV,
+
+       SSN_DELAY_SHIFT = 10,   /* SSN to Sclk_out delay */
+       SSN_DELAY_MASK  = 1,
+       SSN_DELAY_HALF  = 0,    /* 1/2 sclk_out cycle */
+       SSN_DELAY_ONE   = 1,    /* 1 sclk_out cycle */
+
+       SEM_SHIFT       = 11,   /* Serial Endian Mode */
+       SEM_MASK        = 1,
+       SEM_LITTLE      = 0,    /* little endian */
+       SEM_BIG,                /* big endian */
+
+       FBM_SHIFT       = 12,   /* First Bit Mode */
+       FBM_MASK        = 1,
+       FBM_MSB         = 0,    /* first bit is MSB */
+       FBM_LSB,                /* first bit in LSB */
+
+       HALF_WORD_TX_SHIFT = 13,        /* Byte and Halfword Transform */
+       HALF_WORD_MASK  = 1,
+       HALF_WORD_ON    = 0,    /* apb 16bit write/read, spi 8bit write/read */
+       HALF_WORD_OFF,          /* apb 8bit write/read, spi 8bit write/read */
+
+       RXDSD_SHIFT     = 14,   /* Rxd Sample Delay, in cycles */
+       RXDSD_MASK      = 3,
+
+       FRF_SHIFT       = 16,   /* Frame Format */
+       FRF_MASK        = 3,
+       FRF_SPI         = 0,    /* Motorola SPI */
+       FRF_SSP,                        /* Texas Instruments SSP*/
+       FRF_MICROWIRE,          /* National Semiconductors Microwire */
+       FRF_RESV,
+
+       TMOD_SHIFT      = 18,   /* Transfer Mode */
+       TMOD_MASK       = 3,
+       TMOD_TR         = 0,    /* xmit & recv */
+       TMOD_TO,                /* xmit only */
+       TMOD_RO,                /* recv only */
+       TMOD_RESV,
+
+       OMOD_SHIFT      = 20,   /* Operation Mode */
+       OMOD_MASK       = 1,
+       OMOD_MASTER     = 0,    /* Master Mode */
+       OMOD_SLAVE,             /* Slave Mode */
+};
+
+/* SR */
+enum {
+       SR_MASK         = 0x7f,
+       SR_BUSY         = 1 << 0,
+       SR_TF_FULL      = 1 << 1,
+       SR_TF_EMPT      = 1 << 2,
+       SR_RF_EMPT      = 1 << 3,
+       SR_RF_FULL      = 1 << 4,
+};
+
+#define ROCKCHIP_SPI_TIMEOUT_MS                1000
+#define ROCKCHIP_SPI_MAX_RATE          48000000
+
+#endif /* __RK_SPI_H */