| /* |
| * 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 <linux/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 { |
| s32 frequency; /* Default clock frequency, -1 for none */ |
| fdt_addr_t base; |
| uint deactivate_delay_us; /* Delay to wait after deactivate */ |
| uint activate_delay_us; /* Delay to wait after activate */ |
| }; |
| |
| struct rockchip_spi_priv { |
| struct rockchip_spi *regs; |
| struct clk clk; |
| unsigned int max_freq; |
| unsigned int mode; |
| 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 last_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(®s->ctrlr0)); |
| debug("ctrl1: \t\t0x%08x\n", readl(®s->ctrlr1)); |
| debug("ssienr: \t\t0x%08x\n", readl(®s->enr)); |
| debug("ser: \t\t0x%08x\n", readl(®s->ser)); |
| debug("baudr: \t\t0x%08x\n", readl(®s->baudr)); |
| debug("txftlr: \t\t0x%08x\n", readl(®s->txftlr)); |
| debug("rxftlr: \t\t0x%08x\n", readl(®s->rxftlr)); |
| debug("txflr: \t\t0x%08x\n", readl(®s->txflr)); |
| debug("rxflr: \t\t0x%08x\n", readl(®s->rxflr)); |
| debug("sr: \t\t0x%08x\n", readl(®s->sr)); |
| debug("imr: \t\t0x%08x\n", readl(®s->imr)); |
| debug("isr: \t\t0x%08x\n", readl(®s->isr)); |
| debug("dmacr: \t\t0x%08x\n", readl(®s->dmacr)); |
| debug("dmatdlr: \t0x%08x\n", readl(®s->dmatdlr)); |
| debug("dmardlr: \t0x%08x\n", readl(®s->dmardlr)); |
| } |
| |
| static void rkspi_enable_chip(struct rockchip_spi *regs, bool enable) |
| { |
| writel(enable ? 1 : 0, ®s->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); |
| priv->last_speed_hz = speed; |
| } |
| |
| static int rkspi_wait_till_not_busy(struct rockchip_spi *regs) |
| { |
| unsigned long start; |
| |
| start = get_timer(0); |
| while (readl(®s->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 udevice *dev, uint cs) |
| { |
| struct udevice *bus = dev->parent; |
| struct rockchip_spi_platdata *plat = bus->platdata; |
| struct rockchip_spi_priv *priv = dev_get_priv(bus); |
| struct rockchip_spi *regs = priv->regs; |
| |
| debug("activate cs%u\n", cs); |
| writel(1 << cs, ®s->ser); |
| if (plat->activate_delay_us) |
| udelay(plat->activate_delay_us); |
| } |
| |
| static void spi_cs_deactivate(struct udevice *dev, uint cs) |
| { |
| struct udevice *bus = dev->parent; |
| struct rockchip_spi_platdata *plat = bus->platdata; |
| struct rockchip_spi_priv *priv = dev_get_priv(bus); |
| struct rockchip_spi *regs = priv->regs; |
| |
| debug("deactivate cs%u\n", cs); |
| writel(0, ®s->ser); |
| |
| /* Remember time of this transaction so we can honour the bus delay */ |
| if (plat->deactivate_delay_us) |
| priv->last_transaction_us = timer_get_us(); |
| } |
| |
| static int rockchip_spi_ofdata_to_platdata(struct udevice *bus) |
| { |
| struct rockchip_spi_platdata *plat = bus->platdata; |
| struct rockchip_spi_priv *priv = dev_get_priv(bus); |
| const void *blob = gd->fdt_blob; |
| int node = bus->of_offset; |
| int ret; |
| |
| plat->base = dev_get_addr(bus); |
| |
| ret = clk_get_by_index(bus, 0, &priv->clk); |
| if (ret < 0) { |
| debug("%s: Could not get clock for %s: %d\n", __func__, |
| bus->name, ret); |
| return 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); |
| plat->activate_delay_us = fdtdec_get_int(blob, node, |
| "spi-activate-delay", 0); |
| debug("%s: base=%x, max-frequency=%d, deactivate_delay=%d\n", |
| __func__, (uint)plat->base, 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; |
| |
| /* |
| * Use 99 MHz as our clock since it divides nicely into 594 MHz which |
| * is the assumed speed for CLK_GENERAL. |
| */ |
| ret = clk_set_rate(&priv->clk, 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_priv *priv = dev_get_priv(bus); |
| struct rockchip_spi *regs = priv->regs; |
| u8 spi_dfs, spi_tf; |
| uint ctrlr0; |
| |
| /* 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; |
| } |
| |
| if (priv->speed_hz != priv->last_speed_hz) |
| rkspi_set_clk(priv, priv->speed_hz); |
| |
| /* Operation Mode */ |
| ctrlr0 = OMOD_MASTER << OMOD_SHIFT; |
| |
| /* Data Frame Size */ |
| ctrlr0 |= spi_dfs << 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_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, ®s->ctrlr0); |
| |
| return 0; |
| } |
| |
| static int rockchip_spi_release_bus(struct udevice *dev) |
| { |
| struct udevice *bus = dev->parent; |
| struct rockchip_spi_priv *priv = dev_get_priv(bus); |
| |
| rkspi_enable_chip(priv->regs, false); |
| |
| 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(dev, slave_plat->cs); |
| |
| while (len > 0) { |
| int todo = min(len, 0xffff); |
| |
| rkspi_enable_chip(regs, false); |
| writel(todo - 1, ®s->ctrlr1); |
| rkspi_enable_chip(regs, true); |
| |
| toread = todo; |
| towrite = todo; |
| while (toread || towrite) { |
| u32 status = readl(®s->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(dev, 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, |
| }; |