diff options
Diffstat (limited to 'drivers/spi/bcmstb_spi.c')
| -rw-r--r-- | drivers/spi/bcmstb_spi.c | 439 |
1 files changed, 439 insertions, 0 deletions
diff --git a/drivers/spi/bcmstb_spi.c b/drivers/spi/bcmstb_spi.c new file mode 100644 index 00000000000..fb1dc46b704 --- /dev/null +++ b/drivers/spi/bcmstb_spi.c @@ -0,0 +1,439 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * (C) Copyright 2018 Cisco Systems, Inc. + * + * Author: Thomas Fitzsimmons <fitzsim@fitzsim.org> + */ + +#include <asm/io.h> +#include <command.h> +#include <config.h> +#include <dm.h> +#include <errno.h> +#include <fdtdec.h> +#include <linux/bitops.h> +#include <linux/delay.h> +#include <log.h> +#include <malloc.h> +#include <spi.h> +#include <time.h> + +DECLARE_GLOBAL_DATA_PTR; + +#define SPBR_MIN 8 +#define BITS_PER_WORD 8 + +#define NUM_TXRAM 32 +#define NUM_RXRAM 32 +#define NUM_CDRAM 16 + +/* hif_mspi register structure. */ +struct bcmstb_hif_mspi_regs { + u32 spcr0_lsb; /* 0x000 */ + u32 spcr0_msb; /* 0x004 */ + u32 spcr1_lsb; /* 0x008 */ + u32 spcr1_msb; /* 0x00c */ + u32 newqp; /* 0x010 */ + u32 endqp; /* 0x014 */ + u32 spcr2; /* 0x018 */ + u32 reserved0; /* 0x01c */ + u32 mspi_status; /* 0x020 */ + u32 cptqp; /* 0x024 */ + u32 spcr3; /* 0x028 */ + u32 revision; /* 0x02c */ + u32 reserved1[4]; /* 0x030 */ + u32 txram[NUM_TXRAM]; /* 0x040 */ + u32 rxram[NUM_RXRAM]; /* 0x0c0 */ + u32 cdram[NUM_CDRAM]; /* 0x140 */ + u32 write_lock; /* 0x180 */ +}; + +/* hif_mspi masks. */ +#define HIF_MSPI_SPCR2_CONT_AFTER_CMD_MASK 0x00000080 +#define HIF_MSPI_SPCR2_SPE_MASK 0x00000040 +#define HIF_MSPI_SPCR2_SPIFIE_MASK 0x00000020 +#define HIF_MSPI_WRITE_LOCK_WRITE_LOCK_MASK 0x00000001 + +/* bspi offsets. */ +#define BSPI_MAST_N_BOOT_CTRL 0x008 + +/* bspi_raf is not used in this driver. */ + +/* hif_spi_intr2 offsets and masks. */ +#define HIF_SPI_INTR2_CPU_CLEAR 0x08 +#define HIF_SPI_INTR2_CPU_MASK_SET 0x10 +#define HIF_SPI_INTR2_CPU_MASK_CLEAR 0x14 +#define HIF_SPI_INTR2_CPU_SET_MSPI_DONE_MASK 0x00000020 + +/* SPI transfer timeout in milliseconds. */ +#define HIF_MSPI_WAIT 10 + +enum bcmstb_base_type { + HIF_MSPI, + BSPI, + HIF_SPI_INTR2, + CS_REG, + BASE_LAST, +}; + +struct bcmstb_spi_platdata { + void *base[4]; +}; + +struct bcmstb_spi_priv { + struct bcmstb_hif_mspi_regs *regs; + void *bspi; + void *hif_spi_intr2; + void *cs_reg; + int default_cs; + int curr_cs; + uint tx_slot; + uint rx_slot; + u8 saved_cmd[NUM_CDRAM]; + uint saved_cmd_len; + void *saved_din_addr; +}; + +static int bcmstb_spi_ofdata_to_platdata(struct udevice *bus) +{ + struct bcmstb_spi_platdata *plat = dev_get_platdata(bus); + const void *fdt = gd->fdt_blob; + int node = dev_of_offset(bus); + int ret = 0; + int i = 0; + struct fdt_resource resource = { 0 }; + char *names[BASE_LAST] = { "hif_mspi", "bspi", "hif_spi_intr2", + "cs_reg" }; + const phys_addr_t defaults[BASE_LAST] = { BCMSTB_HIF_MSPI_BASE, + BCMSTB_BSPI_BASE, + BCMSTB_HIF_SPI_INTR2, + BCMSTB_CS_REG }; + + for (i = 0; i < BASE_LAST; i++) { + plat->base[i] = (void *)defaults[i]; + + ret = fdt_get_named_resource(fdt, node, "reg", "reg-names", + names[i], &resource); + if (ret) { + printf("%s: Assuming BCMSTB SPI %s address 0x0x%p\n", + __func__, names[i], (void *)defaults[i]); + } else { + plat->base[i] = (void *)resource.start; + debug("BCMSTB SPI %s address: 0x0x%p\n", + names[i], (void *)plat->base[i]); + } + } + + return 0; +} + +static void bcmstb_spi_hw_set_parms(struct bcmstb_spi_priv *priv) +{ + writel(SPBR_MIN, &priv->regs->spcr0_lsb); + writel(BITS_PER_WORD << 2 | SPI_MODE_3, &priv->regs->spcr0_msb); +} + +static void bcmstb_spi_enable_interrupt(void *base, u32 mask) +{ + void *reg = base + HIF_SPI_INTR2_CPU_MASK_CLEAR; + + writel(readl(reg) | mask, reg); + readl(reg); +} + +static void bcmstb_spi_disable_interrupt(void *base, u32 mask) +{ + void *reg = base + HIF_SPI_INTR2_CPU_MASK_SET; + + writel(readl(reg) | mask, reg); + readl(reg); +} + +static void bcmstb_spi_clear_interrupt(void *base, u32 mask) +{ + void *reg = base + HIF_SPI_INTR2_CPU_CLEAR; + + writel(readl(reg) | mask, reg); + readl(reg); +} + +static int bcmstb_spi_probe(struct udevice *bus) +{ + struct bcmstb_spi_platdata *plat = dev_get_platdata(bus); + struct bcmstb_spi_priv *priv = dev_get_priv(bus); + + priv->regs = plat->base[HIF_MSPI]; + priv->bspi = plat->base[BSPI]; + priv->hif_spi_intr2 = plat->base[HIF_SPI_INTR2]; + priv->cs_reg = plat->base[CS_REG]; + priv->default_cs = 0; + priv->curr_cs = -1; + priv->tx_slot = 0; + priv->rx_slot = 0; + memset(priv->saved_cmd, 0, NUM_CDRAM); + priv->saved_cmd_len = 0; + priv->saved_din_addr = NULL; + + debug("spi_xfer: tx regs: 0x%p\n", &priv->regs->txram[0]); + debug("spi_xfer: rx regs: 0x%p\n", &priv->regs->rxram[0]); + + /* Disable BSPI. */ + writel(1, priv->bspi + BSPI_MAST_N_BOOT_CTRL); + readl(priv->bspi + BSPI_MAST_N_BOOT_CTRL); + + /* Set up interrupts. */ + bcmstb_spi_disable_interrupt(priv->hif_spi_intr2, 0xffffffff); + bcmstb_spi_clear_interrupt(priv->hif_spi_intr2, 0xffffffff); + bcmstb_spi_enable_interrupt(priv->hif_spi_intr2, + HIF_SPI_INTR2_CPU_SET_MSPI_DONE_MASK); + + /* Set up control registers. */ + writel(0, &priv->regs->spcr1_lsb); + writel(0, &priv->regs->spcr1_msb); + writel(0, &priv->regs->newqp); + writel(0, &priv->regs->endqp); + writel(HIF_MSPI_SPCR2_SPIFIE_MASK, &priv->regs->spcr2); + writel(0, &priv->regs->spcr3); + + bcmstb_spi_hw_set_parms(priv); + + return 0; +} + +static void bcmstb_spi_submit(struct bcmstb_spi_priv *priv, bool done) +{ + debug("WR NEWQP: %d\n", 0); + writel(0, &priv->regs->newqp); + + debug("WR ENDQP: %d\n", priv->tx_slot - 1); + writel(priv->tx_slot - 1, &priv->regs->endqp); + + if (done) { + debug("WR CDRAM[%d]: %02x\n", priv->tx_slot - 1, + readl(&priv->regs->cdram[priv->tx_slot - 1]) & ~0x80); + writel(readl(&priv->regs->cdram[priv->tx_slot - 1]) & ~0x80, + &priv->regs->cdram[priv->tx_slot - 1]); + } + + /* Force chip select first time. */ + if (priv->curr_cs != priv->default_cs) { + debug("spi_xfer: switching chip select to %d\n", + priv->default_cs); + writel((readl(priv->cs_reg) & ~0xff) | (1 << priv->default_cs), + priv->cs_reg); + readl(priv->cs_reg); + udelay(10); + priv->curr_cs = priv->default_cs; + } + + debug("WR WRITE_LOCK: %02x\n", 1); + writel((readl(&priv->regs->write_lock) & + ~HIF_MSPI_WRITE_LOCK_WRITE_LOCK_MASK) | 1, + &priv->regs->write_lock); + readl(&priv->regs->write_lock); + + debug("WR SPCR2: %02x\n", + HIF_MSPI_SPCR2_SPIFIE_MASK | + HIF_MSPI_SPCR2_SPE_MASK | + HIF_MSPI_SPCR2_CONT_AFTER_CMD_MASK); + writel(HIF_MSPI_SPCR2_SPIFIE_MASK | + HIF_MSPI_SPCR2_SPE_MASK | + HIF_MSPI_SPCR2_CONT_AFTER_CMD_MASK, + &priv->regs->spcr2); +} + +static int bcmstb_spi_wait(struct bcmstb_spi_priv *priv) +{ + u32 start_time = get_timer(0); + u32 status = readl(&priv->regs->mspi_status); + + while (!(status & 1)) { + if (get_timer(start_time) > HIF_MSPI_WAIT) + return -ETIMEDOUT; + status = readl(&priv->regs->mspi_status); + } + + writel(readl(&priv->regs->mspi_status) & ~1, &priv->regs->mspi_status); + bcmstb_spi_clear_interrupt(priv->hif_spi_intr2, + HIF_SPI_INTR2_CPU_SET_MSPI_DONE_MASK); + + return 0; +} + +static int bcmstb_spi_xfer(struct udevice *dev, unsigned int bitlen, + const void *dout, void *din, unsigned long flags) +{ + uint len = bitlen / 8; + uint tx_len = len; + uint rx_len = len; + const u8 *out_bytes = (u8 *)dout; + u8 *in_bytes = (u8 *)din; + struct udevice *bus = dev_get_parent(dev); + struct bcmstb_spi_priv *priv = dev_get_priv(bus); + struct bcmstb_hif_mspi_regs *regs = priv->regs; + + debug("spi_xfer: %d, t: 0x%p, r: 0x%p, f: %lx\n", + len, dout, din, flags); + debug("spi_xfer: chip select: %x\n", readl(priv->cs_reg) & 0xff); + debug("spi_xfer: tx addr: 0x%p\n", ®s->txram[0]); + debug("spi_xfer: rx addr: 0x%p\n", ®s->rxram[0]); + debug("spi_xfer: cd addr: 0x%p\n", ®s->cdram[0]); + + if (flags & SPI_XFER_END) { + debug("spi_xfer: clearing saved din address: 0x%p\n", + priv->saved_din_addr); + priv->saved_din_addr = NULL; + priv->saved_cmd_len = 0; + memset(priv->saved_cmd, 0, NUM_CDRAM); + } + + if (bitlen == 0) + return 0; + + if (bitlen % 8) { + printf("%s: Non-byte-aligned transfer\n", __func__); + return -EOPNOTSUPP; + } + + if (flags & ~(SPI_XFER_BEGIN | SPI_XFER_END)) { + printf("%s: Unsupported flags: %lx\n", __func__, flags); + return -EOPNOTSUPP; + } + + if (flags & SPI_XFER_BEGIN) { + priv->tx_slot = 0; + priv->rx_slot = 0; + + if (out_bytes && len > NUM_CDRAM) { + printf("%s: Unable to save transfer\n", __func__); + return -EOPNOTSUPP; + } + + if (out_bytes && !(flags & SPI_XFER_END)) { + /* + * This is the start of a transmit operation + * that will need repeating if the calling + * code polls for the result. Save it for + * subsequent transmission. + */ + debug("spi_xfer: saving command: %x, %d\n", + out_bytes[0], len); + priv->saved_cmd_len = len; + memcpy(priv->saved_cmd, out_bytes, priv->saved_cmd_len); + } + } + + if (!(flags & (SPI_XFER_BEGIN | SPI_XFER_END))) { + if (priv->saved_din_addr == din) { + /* + * The caller is polling for status. Repeat + * the last transmission. + */ + int ret = 0; + + debug("spi_xfer: Making recursive call\n"); + ret = bcmstb_spi_xfer(dev, priv->saved_cmd_len * 8, + priv->saved_cmd, NULL, + SPI_XFER_BEGIN); + if (ret) { + printf("%s: Recursive call failed\n", __func__); + return ret; + } + } else { + debug("spi_xfer: saving din address: 0x%p\n", din); + priv->saved_din_addr = din; + } + } + + while (rx_len > 0) { + priv->rx_slot = priv->tx_slot; + + while (priv->tx_slot < NUM_CDRAM && tx_len > 0) { + bcmstb_spi_hw_set_parms(priv); + debug("WR TXRAM[%d]: %02x\n", priv->tx_slot, + out_bytes ? out_bytes[len - tx_len] : 0xff); + writel(out_bytes ? out_bytes[len - tx_len] : 0xff, + ®s->txram[priv->tx_slot << 1]); + debug("WR CDRAM[%d]: %02x\n", priv->tx_slot, 0x8e); + writel(0x8e, ®s->cdram[priv->tx_slot]); + priv->tx_slot++; + tx_len--; + if (!in_bytes) + rx_len--; + } + + debug("spi_xfer: early return clauses: %d, %d, %d\n", + len <= NUM_CDRAM, + !in_bytes, + (flags & (SPI_XFER_BEGIN | + SPI_XFER_END)) == SPI_XFER_BEGIN); + if (len <= NUM_CDRAM && + !in_bytes && + (flags & (SPI_XFER_BEGIN | SPI_XFER_END)) == SPI_XFER_BEGIN) + return 0; + + bcmstb_spi_submit(priv, tx_len == 0); + + if (bcmstb_spi_wait(priv) == -ETIMEDOUT) { + printf("%s: Timed out\n", __func__); + return -ETIMEDOUT; + } + + priv->tx_slot %= NUM_CDRAM; + + if (in_bytes) { + while (priv->rx_slot < NUM_CDRAM && rx_len > 0) { + in_bytes[len - rx_len] = + readl(®s->rxram[(priv->rx_slot << 1) + + 1]) + & 0xff; + debug("RD RXRAM[%d]: %02x\n", + priv->rx_slot, in_bytes[len - rx_len]); + priv->rx_slot++; + rx_len--; + } + } + } + + if (flags & SPI_XFER_END) { + debug("WR WRITE_LOCK: %02x\n", 0); + writel((readl(&priv->regs->write_lock) & + ~HIF_MSPI_WRITE_LOCK_WRITE_LOCK_MASK) | 0, + &priv->regs->write_lock); + readl(&priv->regs->write_lock); + } + + return 0; +} + +static int bcmstb_spi_set_speed(struct udevice *dev, uint speed) +{ + return 0; +} + +static int bcmstb_spi_set_mode(struct udevice *dev, uint mode) +{ + return 0; +} + +static const struct dm_spi_ops bcmstb_spi_ops = { + .xfer = bcmstb_spi_xfer, + .set_speed = bcmstb_spi_set_speed, + .set_mode = bcmstb_spi_set_mode, +}; + +static const struct udevice_id bcmstb_spi_id[] = { + { .compatible = "brcm,spi-brcmstb" }, + { } +}; + +U_BOOT_DRIVER(bcmstb_spi) = { + .name = "bcmstb_spi", + .id = UCLASS_SPI, + .of_match = bcmstb_spi_id, + .ops = &bcmstb_spi_ops, + .ofdata_to_platdata = bcmstb_spi_ofdata_to_platdata, + .probe = bcmstb_spi_probe, + .platdata_auto_alloc_size = sizeof(struct bcmstb_spi_platdata), + .priv_auto_alloc_size = sizeof(struct bcmstb_spi_priv), +}; |