// SPDX-License-Identifier: GPL-2.0+ /* * Copyright (C) 2017 Álvaro Fernández Rojas * * Derived from linux/drivers/spi/spi-bcm63xx.c: * Copyright (C) 2009-2012 Florian Fainelli * Copyright (C) 2010 Tanguy Bouzeloc */ #include #include #include #include #include #include #include #include #include /* BCM6348 SPI core */ #define SPI_6348_CLK 0x06 #define SPI_6348_CMD 0x00 #define SPI_6348_CTL 0x40 #define SPI_6348_CTL_SHIFT 6 #define SPI_6348_FILL 0x07 #define SPI_6348_IR_MASK 0x04 #define SPI_6348_IR_STAT 0x02 #define SPI_6348_RX 0x80 #define SPI_6348_RX_SIZE 0x3f #define SPI_6348_TX 0x41 #define SPI_6348_TX_SIZE 0x3f /* BCM6358 SPI core */ #define SPI_6358_CLK 0x706 #define SPI_6358_CMD 0x700 #define SPI_6358_CTL 0x000 #define SPI_6358_CTL_SHIFT 14 #define SPI_6358_FILL 0x707 #define SPI_6358_IR_MASK 0x702 #define SPI_6358_IR_STAT 0x704 #define SPI_6358_RX 0x400 #define SPI_6358_RX_SIZE 0x220 #define SPI_6358_TX 0x002 #define SPI_6358_TX_SIZE 0x21e /* SPI Clock register */ #define SPI_CLK_SHIFT 0 #define SPI_CLK_20MHZ (0 << SPI_CLK_SHIFT) #define SPI_CLK_0_391MHZ (1 << SPI_CLK_SHIFT) #define SPI_CLK_0_781MHZ (2 << SPI_CLK_SHIFT) #define SPI_CLK_1_563MHZ (3 << SPI_CLK_SHIFT) #define SPI_CLK_3_125MHZ (4 << SPI_CLK_SHIFT) #define SPI_CLK_6_250MHZ (5 << SPI_CLK_SHIFT) #define SPI_CLK_12_50MHZ (6 << SPI_CLK_SHIFT) #define SPI_CLK_25MHZ (7 << SPI_CLK_SHIFT) #define SPI_CLK_MASK (7 << SPI_CLK_SHIFT) #define SPI_CLK_SSOFF_SHIFT 3 #define SPI_CLK_SSOFF_2 (2 << SPI_CLK_SSOFF_SHIFT) #define SPI_CLK_SSOFF_MASK (7 << SPI_CLK_SSOFF_SHIFT) #define SPI_CLK_BSWAP_SHIFT 7 #define SPI_CLK_BSWAP_MASK (1 << SPI_CLK_BSWAP_SHIFT) /* SPI Command register */ #define SPI_CMD_OP_SHIFT 0 #define SPI_CMD_OP_START (0x3 << SPI_CMD_OP_SHIFT) #define SPI_CMD_SLAVE_SHIFT 4 #define SPI_CMD_SLAVE_MASK (0xf << SPI_CMD_SLAVE_SHIFT) #define SPI_CMD_PREPEND_SHIFT 8 #define SPI_CMD_PREPEND_BYTES 0xf #define SPI_CMD_3WIRE_SHIFT 12 #define SPI_CMD_3WIRE_MASK (1 << SPI_CMD_3WIRE_SHIFT) /* SPI Control register */ #define SPI_CTL_TYPE_FD_RW 0 #define SPI_CTL_TYPE_HD_W 1 #define SPI_CTL_TYPE_HD_R 2 /* SPI Interrupt registers */ #define SPI_IR_DONE_SHIFT 0 #define SPI_IR_DONE_MASK (1 << SPI_IR_DONE_SHIFT) #define SPI_IR_RXOVER_SHIFT 1 #define SPI_IR_RXOVER_MASK (1 << SPI_IR_RXOVER_SHIFT) #define SPI_IR_TXUNDER_SHIFT 2 #define SPI_IR_TXUNDER_MASK (1 << SPI_IR_TXUNDER_SHIFT) #define SPI_IR_TXOVER_SHIFT 3 #define SPI_IR_TXOVER_MASK (1 << SPI_IR_TXOVER_SHIFT) #define SPI_IR_RXUNDER_SHIFT 4 #define SPI_IR_RXUNDER_MASK (1 << SPI_IR_RXUNDER_SHIFT) #define SPI_IR_CLEAR_MASK (SPI_IR_DONE_MASK |\ SPI_IR_RXOVER_MASK |\ SPI_IR_TXUNDER_MASK |\ SPI_IR_TXOVER_MASK |\ SPI_IR_RXUNDER_MASK) enum bcm63xx_regs_spi { SPI_CLK, SPI_CMD, SPI_CTL, SPI_CTL_SHIFT, SPI_FILL, SPI_IR_MASK, SPI_IR_STAT, SPI_RX, SPI_RX_SIZE, SPI_TX, SPI_TX_SIZE, }; struct bcm63xx_spi_priv { const unsigned long *regs; void __iomem *base; size_t tx_bytes; uint8_t num_cs; }; #define SPI_CLK_CNT 8 static const unsigned bcm63xx_spi_freq_table[SPI_CLK_CNT][2] = { { 25000000, SPI_CLK_25MHZ }, { 20000000, SPI_CLK_20MHZ }, { 12500000, SPI_CLK_12_50MHZ }, { 6250000, SPI_CLK_6_250MHZ }, { 3125000, SPI_CLK_3_125MHZ }, { 1563000, SPI_CLK_1_563MHZ }, { 781000, SPI_CLK_0_781MHZ }, { 391000, SPI_CLK_0_391MHZ } }; static int bcm63xx_spi_cs_info(struct udevice *bus, uint cs, struct spi_cs_info *info) { struct bcm63xx_spi_priv *priv = dev_get_priv(bus); if (cs >= priv->num_cs) { printf("no cs %u\n", cs); return -EINVAL; } return 0; } static int bcm63xx_spi_set_mode(struct udevice *bus, uint mode) { struct bcm63xx_spi_priv *priv = dev_get_priv(bus); const unsigned long *regs = priv->regs; if (mode & SPI_LSB_FIRST) setbits_8(priv->base + regs[SPI_CLK], SPI_CLK_BSWAP_MASK); else clrbits_8(priv->base + regs[SPI_CLK], SPI_CLK_BSWAP_MASK); return 0; } static int bcm63xx_spi_set_speed(struct udevice *bus, uint speed) { struct bcm63xx_spi_priv *priv = dev_get_priv(bus); const unsigned long *regs = priv->regs; uint8_t clk_cfg; int i; /* default to lowest clock configuration */ clk_cfg = SPI_CLK_0_391MHZ; /* find the closest clock configuration */ for (i = 0; i < SPI_CLK_CNT; i++) { if (speed >= bcm63xx_spi_freq_table[i][0]) { clk_cfg = bcm63xx_spi_freq_table[i][1]; break; } } /* write clock configuration */ clrsetbits_8(priv->base + regs[SPI_CLK], SPI_CLK_SSOFF_MASK | SPI_CLK_MASK, clk_cfg | SPI_CLK_SSOFF_2); return 0; } /* * BCM63xx SPI driver doesn't allow keeping CS active between transfers since * they are HW controlled. * 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. * * This implementation takes advantage of the prepend mechanism and combines * multiple transfers into a single one where possible (single/multiple write * transfer(s) followed by a final read/write transfer). * However, it's not possible to buffer reads, which means that read transfers * should always be done as the final ones. * On the other hand, take into account that combining write transfers into * a single one is just buffering and doesn't require prepend mechanism. */ static int bcm63xx_spi_xfer(struct udevice *dev, unsigned int bitlen, const void *dout, void *din, unsigned long flags) { struct bcm63xx_spi_priv *priv = dev_get_priv(dev->parent); const unsigned long *regs = priv->regs; size_t data_bytes = bitlen / 8; if (flags & SPI_XFER_BEGIN) { /* clear prepends */ priv->tx_bytes = 0; /* initialize hardware */ writeb_be(0, priv->base + regs[SPI_IR_MASK]); } if (din) { /* buffering reads not possible since cs is hw controlled */ if (!(flags & SPI_XFER_END)) { printf("unable to buffer reads\n"); return -EINVAL; } /* check rx size */ if (data_bytes > regs[SPI_RX_SIZE]) { printf("max rx bytes exceeded\n"); return -EMSGSIZE; } } if (dout) { /* check tx size */ if (priv->tx_bytes + data_bytes > regs[SPI_TX_SIZE]) { printf("max tx bytes exceeded\n"); return -EMSGSIZE; } /* copy tx data */ memcpy_toio(priv->base + regs[SPI_TX] + priv->tx_bytes, dout, data_bytes); priv->tx_bytes += data_bytes; } if (flags & SPI_XFER_END) { struct dm_spi_slave_plat *plat = dev_get_parent_plat(dev); uint16_t val, cmd; int ret; /* determine control config */ if (dout && !din) { /* buffered write transfers */ val = priv->tx_bytes; val |= (SPI_CTL_TYPE_HD_W << regs[SPI_CTL_SHIFT]); priv->tx_bytes = 0; } else { if (dout && din && (flags & SPI_XFER_ONCE)) { /* full duplex read/write */ val = data_bytes; val |= (SPI_CTL_TYPE_FD_RW << regs[SPI_CTL_SHIFT]); priv->tx_bytes = 0; } else { /* prepended write transfer */ val = data_bytes; val |= (SPI_CTL_TYPE_HD_R << regs[SPI_CTL_SHIFT]); if (priv->tx_bytes > SPI_CMD_PREPEND_BYTES) { printf("max prepend bytes exceeded\n"); return -EMSGSIZE; } } } if (regs[SPI_CTL_SHIFT] >= 8) writew_be(val, priv->base + regs[SPI_CTL]); else writeb_be(val, priv->base + regs[SPI_CTL]); /* clear interrupts */ writeb_be(SPI_IR_CLEAR_MASK, priv->base + regs[SPI_IR_STAT]); /* issue the transfer */ cmd = SPI_CMD_OP_START; cmd |= (plat->cs << SPI_CMD_SLAVE_SHIFT) & SPI_CMD_SLAVE_MASK; cmd |= (priv->tx_bytes << SPI_CMD_PREPEND_SHIFT); if (plat->mode & SPI_3WIRE) cmd |= SPI_CMD_3WIRE_MASK; writew_be(cmd, priv->base + regs[SPI_CMD]); /* enable interrupts */ writeb_be(SPI_IR_DONE_MASK, priv->base + regs[SPI_IR_MASK]); ret = wait_for_bit_8(priv->base + regs[SPI_IR_STAT], SPI_IR_DONE_MASK, true, 1000, false); if (ret) { printf("interrupt timeout\n"); return ret; } /* copy rx data */ if (din) memcpy_fromio(din, priv->base + regs[SPI_RX], data_bytes); } return 0; } static const struct dm_spi_ops bcm63xx_spi_ops = { .cs_info = bcm63xx_spi_cs_info, .set_mode = bcm63xx_spi_set_mode, .set_speed = bcm63xx_spi_set_speed, .xfer = bcm63xx_spi_xfer, }; static const unsigned long bcm6348_spi_regs[] = { [SPI_CLK] = SPI_6348_CLK, [SPI_CMD] = SPI_6348_CMD, [SPI_CTL] = SPI_6348_CTL, [SPI_CTL_SHIFT] = SPI_6348_CTL_SHIFT, [SPI_FILL] = SPI_6348_FILL, [SPI_IR_MASK] = SPI_6348_IR_MASK, [SPI_IR_STAT] = SPI_6348_IR_STAT, [SPI_RX] = SPI_6348_RX, [SPI_RX_SIZE] = SPI_6348_RX_SIZE, [SPI_TX] = SPI_6348_TX, [SPI_TX_SIZE] = SPI_6348_TX_SIZE, }; static const unsigned long bcm6358_spi_regs[] = { [SPI_CLK] = SPI_6358_CLK, [SPI_CMD] = SPI_6358_CMD, [SPI_CTL] = SPI_6358_CTL, [SPI_CTL_SHIFT] = SPI_6358_CTL_SHIFT, [SPI_FILL] = SPI_6358_FILL, [SPI_IR_MASK] = SPI_6358_IR_MASK, [SPI_IR_STAT] = SPI_6358_IR_STAT, [SPI_RX] = SPI_6358_RX, [SPI_RX_SIZE] = SPI_6358_RX_SIZE, [SPI_TX] = SPI_6358_TX, [SPI_TX_SIZE] = SPI_6358_TX_SIZE, }; static const struct udevice_id bcm63xx_spi_ids[] = { { .compatible = "brcm,bcm6348-spi", .data = (ulong)&bcm6348_spi_regs, }, { .compatible = "brcm,bcm6358-spi", .data = (ulong)&bcm6358_spi_regs, }, { /* sentinel */ } }; static int bcm63xx_spi_child_pre_probe(struct udevice *dev) { struct bcm63xx_spi_priv *priv = dev_get_priv(dev->parent); const unsigned long *regs = priv->regs; struct spi_slave *slave = dev_get_parent_priv(dev); struct dm_spi_slave_plat *plat = dev_get_parent_plat(dev); /* check cs */ if (plat->cs >= priv->num_cs) { printf("no cs %u\n", plat->cs); return -ENODEV; } /* max read/write sizes */ slave->max_read_size = regs[SPI_RX_SIZE]; slave->max_write_size = regs[SPI_TX_SIZE]; return 0; } static int bcm63xx_spi_probe(struct udevice *dev) { struct bcm63xx_spi_priv *priv = dev_get_priv(dev); const unsigned long *regs = (const unsigned long *)dev_get_driver_data(dev); struct reset_ctl rst_ctl; struct clk clk; int ret; priv->base = dev_remap_addr(dev); if (!priv->base) return -EINVAL; priv->regs = regs; priv->num_cs = dev_read_u32_default(dev, "num-cs", 8); /* enable clock */ ret = clk_get_by_index(dev, 0, &clk); if (ret < 0) return ret; ret = clk_enable(&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 */ writeb_be(0, priv->base + regs[SPI_IR_MASK]); /* set fill register */ writeb_be(0xff, priv->base + regs[SPI_FILL]); return 0; } U_BOOT_DRIVER(bcm63xx_spi) = { .name = "bcm63xx_spi", .id = UCLASS_SPI, .of_match = bcm63xx_spi_ids, .ops = &bcm63xx_spi_ops, .priv_auto = sizeof(struct bcm63xx_spi_priv), .child_pre_probe = bcm63xx_spi_child_pre_probe, .probe = bcm63xx_spi_probe, };