diff options
Diffstat (limited to 'drivers/spi/spi-meson-spicc.c')
| -rw-r--r-- | drivers/spi/spi-meson-spicc.c | 944 |
1 files changed, 944 insertions, 0 deletions
diff --git a/drivers/spi/spi-meson-spicc.c b/drivers/spi/spi-meson-spicc.c new file mode 100644 index 000000000..1b4195c54 --- /dev/null +++ b/drivers/spi/spi-meson-spicc.c @@ -0,0 +1,944 @@ +/* + * Driver for Amlogic Meson SPI communication controller (SPICC) + * + * Copyright (C) BayLibre, SAS + * Author: Neil Armstrong <narmstrong@baylibre.com> + * + * SPDX-License-Identifier: GPL-2.0+ + */ + +#include <linux/bitfield.h> +#include <linux/clk.h> +#include <linux/clk-provider.h> +#include <linux/device.h> +#include <linux/io.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/of_device.h> +#include <linux/platform_device.h> +#include <linux/spi/spi.h> +#include <linux/types.h> +#include <linux/interrupt.h> +#include <linux/reset.h> + +/* + * The Meson SPICC controller could support DMA based transfers, but is not + * implemented by the vendor code, and while having the registers documentation + * it has never worked on the GXL Hardware. + * The PIO mode is the only mode implemented, and due to badly designed HW : + * - all transfers are cutted in 16 words burst because the FIFO hangs on + * TX underflow, and there is no TX "Half-Empty" interrupt, so we go by + * FIFO max size chunk only + * - CS management is dumb, and goes UP between every burst, so is really a + * "Data Valid" signal than a Chip Select, GPIO link should be used instead + * to have a CS go down over the full transfer + */ + +#define SPICC_MAX_BURST 128 + +/* Register Map */ +#define SPICC_RXDATA 0x00 + +#define SPICC_TXDATA 0x04 + +#define SPICC_CONREG 0x08 +#define SPICC_ENABLE BIT(0) +#define SPICC_MODE_MASTER BIT(1) +#define SPICC_XCH BIT(2) +#define SPICC_SMC BIT(3) +#define SPICC_POL BIT(4) +#define SPICC_PHA BIT(5) +#define SPICC_SSCTL BIT(6) +#define SPICC_SSPOL BIT(7) +#define SPICC_DRCTL_MASK GENMASK(9, 8) +#define SPICC_DRCTL_IGNORE 0 +#define SPICC_DRCTL_FALLING 1 +#define SPICC_DRCTL_LOWLEVEL 2 +#define SPICC_CS_MASK GENMASK(13, 12) +#define SPICC_DATARATE_MASK GENMASK(18, 16) +#define SPICC_DATARATE_DIV4 0 +#define SPICC_DATARATE_DIV8 1 +#define SPICC_DATARATE_DIV16 2 +#define SPICC_DATARATE_DIV32 3 +#define SPICC_BITLENGTH_MASK GENMASK(24, 19) +#define SPICC_BURSTLENGTH_MASK GENMASK(31, 25) + +#define SPICC_INTREG 0x0c +#define SPICC_TE_EN BIT(0) /* TX FIFO Empty Interrupt */ +#define SPICC_TH_EN BIT(1) /* TX FIFO Half-Full Interrupt */ +#define SPICC_TF_EN BIT(2) /* TX FIFO Full Interrupt */ +#define SPICC_RR_EN BIT(3) /* RX FIFO Ready Interrupt */ +#define SPICC_RH_EN BIT(4) /* RX FIFO Half-Full Interrupt */ +#define SPICC_RF_EN BIT(5) /* RX FIFO Full Interrupt */ +#define SPICC_RO_EN BIT(6) /* RX FIFO Overflow Interrupt */ +#define SPICC_TC_EN BIT(7) /* Transfert Complete Interrupt */ + +#define SPICC_DMAREG 0x10 +#define SPICC_DMA_ENABLE BIT(0) +#define SPICC_TXFIFO_THRESHOLD_MASK GENMASK(5, 1) +#define SPICC_RXFIFO_THRESHOLD_MASK GENMASK(10, 6) +#define SPICC_READ_BURST_MASK GENMASK(14, 11) +#define SPICC_WRITE_BURST_MASK GENMASK(18, 15) +#define SPICC_DMA_URGENT BIT(19) +#define SPICC_DMA_THREADID_MASK GENMASK(25, 20) +#define SPICC_DMA_BURSTNUM_MASK GENMASK(31, 26) + +#define SPICC_STATREG 0x14 +#define SPICC_TE BIT(0) /* TX FIFO Empty Interrupt */ +#define SPICC_TH BIT(1) /* TX FIFO Half-Full Interrupt */ +#define SPICC_TF BIT(2) /* TX FIFO Full Interrupt */ +#define SPICC_RR BIT(3) /* RX FIFO Ready Interrupt */ +#define SPICC_RH BIT(4) /* RX FIFO Half-Full Interrupt */ +#define SPICC_RF BIT(5) /* RX FIFO Full Interrupt */ +#define SPICC_RO BIT(6) /* RX FIFO Overflow Interrupt */ +#define SPICC_TC BIT(7) /* Transfert Complete Interrupt */ + +#define SPICC_PERIODREG 0x18 +#define SPICC_PERIOD GENMASK(14, 0) /* Wait cycles */ + +#define SPICC_TESTREG 0x1c +#define SPICC_TXCNT_MASK GENMASK(4, 0) /* TX FIFO Counter */ +#define SPICC_RXCNT_MASK GENMASK(9, 5) /* RX FIFO Counter */ +#define SPICC_SMSTATUS_MASK GENMASK(12, 10) /* State Machine Status */ +#define SPICC_LBC_RO BIT(13) /* Loop Back Control Read-Only */ +#define SPICC_LBC_W1 BIT(14) /* Loop Back Control Write-Only */ +#define SPICC_SWAP_RO BIT(14) /* RX FIFO Data Swap Read-Only */ +#define SPICC_SWAP_W1 BIT(15) /* RX FIFO Data Swap Write-Only */ +#define SPICC_DLYCTL_RO_MASK GENMASK(20, 15) /* Delay Control Read-Only */ +#define SPICC_MO_DELAY_MASK GENMASK(17, 16) /* Master Output Delay */ +#define SPICC_MO_NO_DELAY 0 +#define SPICC_MO_DELAY_1_CYCLE 1 +#define SPICC_MO_DELAY_2_CYCLE 2 +#define SPICC_MO_DELAY_3_CYCLE 3 +#define SPICC_MI_DELAY_MASK GENMASK(19, 18) /* Master Input Delay */ +#define SPICC_MI_NO_DELAY 0 +#define SPICC_MI_DELAY_1_CYCLE 1 +#define SPICC_MI_DELAY_2_CYCLE 2 +#define SPICC_MI_DELAY_3_CYCLE 3 +#define SPICC_MI_CAP_DELAY_MASK GENMASK(21, 20) /* Master Capture Delay */ +#define SPICC_CAP_AHEAD_2_CYCLE 0 +#define SPICC_CAP_AHEAD_1_CYCLE 1 +#define SPICC_CAP_NO_DELAY 2 +#define SPICC_CAP_DELAY_1_CYCLE 3 +#define SPICC_FIFORST_RO_MASK GENMASK(22, 21) /* FIFO Softreset Read-Only */ +#define SPICC_FIFORST_W1_MASK GENMASK(23, 22) /* FIFO Softreset Write-Only */ + +#define SPICC_DRADDR 0x20 /* Read Address of DMA */ + +#define SPICC_DWADDR 0x24 /* Write Address of DMA */ + +#define SPICC_ENH_CTL0 0x38 /* Enhanced Feature */ +#define SPICC_ENH_CLK_CS_DELAY_MASK GENMASK(15, 0) +#define SPICC_ENH_DATARATE_MASK GENMASK(23, 16) +#define SPICC_ENH_DATARATE_EN BIT(24) +#define SPICC_ENH_MOSI_OEN BIT(25) +#define SPICC_ENH_CLK_OEN BIT(26) +#define SPICC_ENH_CS_OEN BIT(27) +#define SPICC_ENH_CLK_CS_DELAY_EN BIT(28) +#define SPICC_ENH_MAIN_CLK_AO BIT(29) + +#define writel_bits_relaxed(mask, val, addr) \ + writel_relaxed((readl_relaxed(addr) & ~(mask)) | (val), addr) + +struct meson_spicc_data { + unsigned int max_speed_hz; + unsigned int min_speed_hz; + unsigned int fifo_size; + bool has_oen; + bool has_enhance_clk_div; + bool has_pclk; +}; + +struct meson_spicc_device { + struct spi_master *master; + struct platform_device *pdev; + void __iomem *base; + struct clk *core; + struct clk *pclk; + struct clk_divider pow2_div; + struct clk *clk; + struct spi_message *message; + struct spi_transfer *xfer; + struct completion done; + const struct meson_spicc_data *data; + u8 *tx_buf; + u8 *rx_buf; + unsigned int bytes_per_word; + unsigned long tx_remain; + unsigned long rx_remain; + unsigned long xfer_remain; +}; + +#define pow2_clk_to_spicc(_div) container_of(_div, struct meson_spicc_device, pow2_div) + +static void meson_spicc_oen_enable(struct meson_spicc_device *spicc) +{ + u32 conf; + + if (!spicc->data->has_oen) + return; + + conf = readl_relaxed(spicc->base + SPICC_ENH_CTL0) | + SPICC_ENH_MOSI_OEN | SPICC_ENH_CLK_OEN | SPICC_ENH_CS_OEN; + + writel_relaxed(conf, spicc->base + SPICC_ENH_CTL0); +} + +static inline bool meson_spicc_txfull(struct meson_spicc_device *spicc) +{ + return !!FIELD_GET(SPICC_TF, + readl_relaxed(spicc->base + SPICC_STATREG)); +} + +static inline bool meson_spicc_rxready(struct meson_spicc_device *spicc) +{ + return FIELD_GET(SPICC_RH | SPICC_RR | SPICC_RF, + readl_relaxed(spicc->base + SPICC_STATREG)); +} + +static inline u32 meson_spicc_pull_data(struct meson_spicc_device *spicc) +{ + unsigned int bytes = spicc->bytes_per_word; + unsigned int byte_shift = 0; + u32 data = 0; + u8 byte; + + while (bytes--) { + byte = *spicc->tx_buf++; + data |= (byte & 0xff) << byte_shift; + byte_shift += 8; + } + + spicc->tx_remain--; + return data; +} + +static inline void meson_spicc_push_data(struct meson_spicc_device *spicc, + u32 data) +{ + unsigned int bytes = spicc->bytes_per_word; + unsigned int byte_shift = 0; + u8 byte; + + while (bytes--) { + byte = (data >> byte_shift) & 0xff; + *spicc->rx_buf++ = byte; + byte_shift += 8; + } + + spicc->rx_remain--; +} + +static inline void meson_spicc_rx(struct meson_spicc_device *spicc) +{ + /* Empty RX FIFO */ + while (spicc->rx_remain && + meson_spicc_rxready(spicc)) + meson_spicc_push_data(spicc, + readl_relaxed(spicc->base + SPICC_RXDATA)); +} + +static inline void meson_spicc_tx(struct meson_spicc_device *spicc) +{ + /* Fill Up TX FIFO */ + while (spicc->tx_remain && + !meson_spicc_txfull(spicc)) + writel_relaxed(meson_spicc_pull_data(spicc), + spicc->base + SPICC_TXDATA); +} + +static inline void meson_spicc_setup_burst(struct meson_spicc_device *spicc) +{ + + unsigned int burst_len = min_t(unsigned int, + spicc->xfer_remain / + spicc->bytes_per_word, + spicc->data->fifo_size); + /* Setup Xfer variables */ + spicc->tx_remain = burst_len; + spicc->rx_remain = burst_len; + spicc->xfer_remain -= burst_len * spicc->bytes_per_word; + + /* Setup burst length */ + writel_bits_relaxed(SPICC_BURSTLENGTH_MASK, + FIELD_PREP(SPICC_BURSTLENGTH_MASK, + burst_len - 1), + spicc->base + SPICC_CONREG); + + /* Fill TX FIFO */ + meson_spicc_tx(spicc); +} + +static irqreturn_t meson_spicc_irq(int irq, void *data) +{ + struct meson_spicc_device *spicc = (void *) data; + + writel_bits_relaxed(SPICC_TC, SPICC_TC, spicc->base + SPICC_STATREG); + + /* Empty RX FIFO */ + meson_spicc_rx(spicc); + + if (!spicc->xfer_remain) { + /* Disable all IRQs */ + writel(0, spicc->base + SPICC_INTREG); + + complete(&spicc->done); + + return IRQ_HANDLED; + } + + /* Setup burst */ + meson_spicc_setup_burst(spicc); + + /* Start burst */ + writel_bits_relaxed(SPICC_XCH, SPICC_XCH, spicc->base + SPICC_CONREG); + + return IRQ_HANDLED; +} + +static void meson_spicc_auto_io_delay(struct meson_spicc_device *spicc) +{ + u32 div, hz; + u32 mi_delay, cap_delay; + u32 conf; + + if (spicc->data->has_enhance_clk_div) { + div = FIELD_GET(SPICC_ENH_DATARATE_MASK, + readl_relaxed(spicc->base + SPICC_ENH_CTL0)); + div++; + div <<= 1; + } else { + div = FIELD_GET(SPICC_DATARATE_MASK, + readl_relaxed(spicc->base + SPICC_CONREG)); + div += 2; + div = 1 << div; + } + + mi_delay = SPICC_MI_NO_DELAY; + cap_delay = SPICC_CAP_AHEAD_2_CYCLE; + hz = clk_get_rate(spicc->clk); + + if (hz >= 100000000) + cap_delay = SPICC_CAP_DELAY_1_CYCLE; + else if (hz >= 80000000) + cap_delay = SPICC_CAP_NO_DELAY; + else if (hz >= 40000000) + cap_delay = SPICC_CAP_AHEAD_1_CYCLE; + else if (div >= 16) + mi_delay = SPICC_MI_DELAY_3_CYCLE; + else if (div >= 8) + mi_delay = SPICC_MI_DELAY_2_CYCLE; + else if (div >= 6) + mi_delay = SPICC_MI_DELAY_1_CYCLE; + + conf = readl_relaxed(spicc->base + SPICC_TESTREG); + conf &= ~(SPICC_MO_DELAY_MASK | SPICC_MI_DELAY_MASK + | SPICC_MI_CAP_DELAY_MASK); + conf |= FIELD_PREP(SPICC_MI_DELAY_MASK, mi_delay); + conf |= FIELD_PREP(SPICC_MI_CAP_DELAY_MASK, cap_delay); + writel_relaxed(conf, spicc->base + SPICC_TESTREG); +} + +static void meson_spicc_setup_xfer(struct meson_spicc_device *spicc, + struct spi_transfer *xfer) +{ + u32 conf, conf_orig; + + /* Read original configuration */ + conf = conf_orig = readl_relaxed(spicc->base + SPICC_CONREG); + + /* Setup word width */ + conf &= ~SPICC_BITLENGTH_MASK; + conf |= FIELD_PREP(SPICC_BITLENGTH_MASK, + (spicc->bytes_per_word << 3) - 1); + + /* Ignore if unchanged */ + if (conf != conf_orig) + writel_relaxed(conf, spicc->base + SPICC_CONREG); + + clk_set_rate(spicc->clk, xfer->speed_hz); + + meson_spicc_auto_io_delay(spicc); + + writel_relaxed(0, spicc->base + SPICC_DMAREG); +} + +static void meson_spicc_reset_fifo(struct meson_spicc_device *spicc) +{ + if (spicc->data->has_oen) + writel_bits_relaxed(SPICC_ENH_MAIN_CLK_AO, + SPICC_ENH_MAIN_CLK_AO, + spicc->base + SPICC_ENH_CTL0); + + writel_bits_relaxed(SPICC_FIFORST_W1_MASK, SPICC_FIFORST_W1_MASK, + spicc->base + SPICC_TESTREG); + + while (meson_spicc_rxready(spicc)) + readl_relaxed(spicc->base + SPICC_RXDATA); + + if (spicc->data->has_oen) + writel_bits_relaxed(SPICC_ENH_MAIN_CLK_AO, 0, + spicc->base + SPICC_ENH_CTL0); +} + +static int meson_spicc_transfer_one(struct spi_master *master, + struct spi_device *spi, + struct spi_transfer *xfer) +{ + struct meson_spicc_device *spicc = spi_master_get_devdata(master); + uint64_t timeout; + + /* Store current transfer */ + spicc->xfer = xfer; + + /* Setup transfer parameters */ + spicc->tx_buf = (u8 *)xfer->tx_buf; + spicc->rx_buf = (u8 *)xfer->rx_buf; + spicc->xfer_remain = xfer->len; + + /* Pre-calculate word size */ + spicc->bytes_per_word = + DIV_ROUND_UP(spicc->xfer->bits_per_word, 8); + + if (xfer->len % spicc->bytes_per_word) + return -EINVAL; + + /* Setup transfer parameters */ + meson_spicc_setup_xfer(spicc, xfer); + + meson_spicc_reset_fifo(spicc); + + /* Setup burst */ + meson_spicc_setup_burst(spicc); + + /* Setup wait for completion */ + reinit_completion(&spicc->done); + + /* For each byte we wait for 8 cycles of the SPI clock */ + timeout = 8LL * MSEC_PER_SEC * xfer->len; + do_div(timeout, xfer->speed_hz); + + /* Add 10us delay between each fifo bursts */ + timeout += ((xfer->len >> 4) * 10) / MSEC_PER_SEC; + + /* Increase it twice and add 200 ms tolerance */ + timeout += timeout + 200; + + /* Start burst */ + writel_bits_relaxed(SPICC_XCH, SPICC_XCH, spicc->base + SPICC_CONREG); + + /* Enable interrupts */ + writel_relaxed(SPICC_TC_EN, spicc->base + SPICC_INTREG); + + if (!wait_for_completion_timeout(&spicc->done, msecs_to_jiffies(timeout))) + return -ETIMEDOUT; + + return 0; +} + +static int meson_spicc_prepare_message(struct spi_master *master, + struct spi_message *message) +{ + struct meson_spicc_device *spicc = spi_master_get_devdata(master); + struct spi_device *spi = message->spi; + u32 conf = readl_relaxed(spicc->base + SPICC_CONREG) & SPICC_DATARATE_MASK; + + /* Store current message */ + spicc->message = message; + + /* Enable Master */ + conf |= SPICC_ENABLE; + conf |= SPICC_MODE_MASTER; + + /* SMC = 0 */ + + /* Setup transfer mode */ + if (spi->mode & SPI_CPOL) + conf |= SPICC_POL; + else + conf &= ~SPICC_POL; + + if (spi->mode & SPI_CPHA) + conf |= SPICC_PHA; + else + conf &= ~SPICC_PHA; + + /* SSCTL = 0 */ + + if (spi->mode & SPI_CS_HIGH) + conf |= SPICC_SSPOL; + else + conf &= ~SPICC_SSPOL; + + if (spi->mode & SPI_READY) + conf |= FIELD_PREP(SPICC_DRCTL_MASK, SPICC_DRCTL_LOWLEVEL); + else + conf |= FIELD_PREP(SPICC_DRCTL_MASK, SPICC_DRCTL_IGNORE); + + /* Select CS */ + conf |= FIELD_PREP(SPICC_CS_MASK, spi->chip_select); + + /* Default 8bit word */ + conf |= FIELD_PREP(SPICC_BITLENGTH_MASK, 8 - 1); + + writel_relaxed(conf, spicc->base + SPICC_CONREG); + + /* Setup no wait cycles by default */ + writel_relaxed(0, spicc->base + SPICC_PERIODREG); + + writel_bits_relaxed(SPICC_LBC_W1, 0, spicc->base + SPICC_TESTREG); + + return 0; +} + +static int meson_spicc_unprepare_transfer(struct spi_master *master) +{ + struct meson_spicc_device *spicc = spi_master_get_devdata(master); + u32 conf = readl_relaxed(spicc->base + SPICC_CONREG) & SPICC_DATARATE_MASK; + + /* Disable all IRQs */ + writel(0, spicc->base + SPICC_INTREG); + + device_reset_optional(&spicc->pdev->dev); + + /* Set default configuration, keeping datarate field */ + writel_relaxed(conf, spicc->base + SPICC_CONREG); + + return 0; +} + +static int meson_spicc_setup(struct spi_device *spi) +{ + if (!spi->controller_state) + spi->controller_state = spi_master_get_devdata(spi->master); + + return 0; +} + +static void meson_spicc_cleanup(struct spi_device *spi) +{ + spi->controller_state = NULL; +} + +/* + * The Clock Mux + * x-----------------x x------------x x------\ + * |---| pow2 fixed div |---| pow2 div |----| | + * | x-----------------x x------------x | | + * src ---| | mux |-- out + * | x-----------------x x------------x | | + * |---| enh fixed div |---| enh div |0---| | + * x-----------------x x------------x x------/ + * + * Clk path for GX series: + * src -> pow2 fixed div -> pow2 div -> out + * + * Clk path for AXG series: + * src -> pow2 fixed div -> pow2 div -> mux -> out + * src -> enh fixed div -> enh div -> mux -> out + * + * Clk path for G12A series: + * pclk -> pow2 fixed div -> pow2 div -> mux -> out + * pclk -> enh fixed div -> enh div -> mux -> out + * + * The pow2 divider is tied to the controller HW state, and the + * divider is only valid when the controller is initialized. + * + * A set of clock ops is added to make sure we don't read/set this + * clock rate while the controller is in an unknown state. + */ + +static unsigned long meson_spicc_pow2_recalc_rate(struct clk_hw *hw, + unsigned long parent_rate) +{ + struct clk_divider *divider = to_clk_divider(hw); + struct meson_spicc_device *spicc = pow2_clk_to_spicc(divider); + + if (!spicc->master->cur_msg) + return 0; + + return clk_divider_ops.recalc_rate(hw, parent_rate); +} + +static int meson_spicc_pow2_determine_rate(struct clk_hw *hw, + struct clk_rate_request *req) +{ + struct clk_divider *divider = to_clk_divider(hw); + struct meson_spicc_device *spicc = pow2_clk_to_spicc(divider); + + if (!spicc->master->cur_msg) + return -EINVAL; + + return clk_divider_ops.determine_rate(hw, req); +} + +static int meson_spicc_pow2_set_rate(struct clk_hw *hw, unsigned long rate, + unsigned long parent_rate) +{ + struct clk_divider *divider = to_clk_divider(hw); + struct meson_spicc_device *spicc = pow2_clk_to_spicc(divider); + + if (!spicc->master->cur_msg) + return -EINVAL; + + return clk_divider_ops.set_rate(hw, rate, parent_rate); +} + +static const struct clk_ops meson_spicc_pow2_clk_ops = { + .recalc_rate = meson_spicc_pow2_recalc_rate, + .determine_rate = meson_spicc_pow2_determine_rate, + .set_rate = meson_spicc_pow2_set_rate, +}; + +static int meson_spicc_pow2_clk_init(struct meson_spicc_device *spicc) +{ + struct device *dev = &spicc->pdev->dev; + struct clk_fixed_factor *pow2_fixed_div; + struct clk_init_data init; + struct clk *clk; + struct clk_parent_data parent_data[2]; + char name[64]; + + memset(&init, 0, sizeof(init)); + memset(&parent_data, 0, sizeof(parent_data)); + + init.parent_data = parent_data; + + /* algorithm for pow2 div: rate = freq / 4 / (2 ^ N) */ + + pow2_fixed_div = devm_kzalloc(dev, sizeof(*pow2_fixed_div), GFP_KERNEL); + if (!pow2_fixed_div) + return -ENOMEM; + + snprintf(name, sizeof(name), "%s#pow2_fixed_div", dev_name(dev)); + init.name = name; + init.ops = &clk_fixed_factor_ops; + init.flags = 0; + if (spicc->data->has_pclk) + parent_data[0].hw = __clk_get_hw(spicc->pclk); + else + parent_data[0].hw = __clk_get_hw(spicc->core); + init.num_parents = 1; + + pow2_fixed_div->mult = 1, + pow2_fixed_div->div = 4, + pow2_fixed_div->hw.init = &init; + + clk = devm_clk_register(dev, &pow2_fixed_div->hw); + if (WARN_ON(IS_ERR(clk))) + return PTR_ERR(clk); + + snprintf(name, sizeof(name), "%s#pow2_div", dev_name(dev)); + init.name = name; + init.ops = &meson_spicc_pow2_clk_ops; + /* + * Set NOCACHE here to make sure we read the actual HW value + * since we reset the HW after each transfer. + */ + init.flags = CLK_SET_RATE_PARENT | CLK_GET_RATE_NOCACHE; + parent_data[0].hw = &pow2_fixed_div->hw; + init.num_parents = 1; + + spicc->pow2_div.shift = 16, + spicc->pow2_div.width = 3, + spicc->pow2_div.flags = CLK_DIVIDER_POWER_OF_TWO, + spicc->pow2_div.reg = spicc->base + SPICC_CONREG; + spicc->pow2_div.hw.init = &init; + + spicc->clk = devm_clk_register(dev, &spicc->pow2_div.hw); + if (WARN_ON(IS_ERR(spicc->clk))) + return PTR_ERR(spicc->clk); + + return 0; +} + +static int meson_spicc_enh_clk_init(struct meson_spicc_device *spicc) +{ + struct device *dev = &spicc->pdev->dev; + struct clk_fixed_factor *enh_fixed_div; + struct clk_divider *enh_div; + struct clk_mux *mux; + struct clk_init_data init; + struct clk *clk; + struct clk_parent_data parent_data[2]; + char name[64]; + + memset(&init, 0, sizeof(init)); + memset(&parent_data, 0, sizeof(parent_data)); + + init.parent_data = parent_data; + + /* algorithm for enh div: rate = freq / 2 / (N + 1) */ + + enh_fixed_div = devm_kzalloc(dev, sizeof(*enh_fixed_div), GFP_KERNEL); + if (!enh_fixed_div) + return -ENOMEM; + + snprintf(name, sizeof(name), "%s#enh_fixed_div", dev_name(dev)); + init.name = name; + init.ops = &clk_fixed_factor_ops; + init.flags = 0; + if (spicc->data->has_pclk) + parent_data[0].hw = __clk_get_hw(spicc->pclk); + else + parent_data[0].hw = __clk_get_hw(spicc->core); + init.num_parents = 1; + + enh_fixed_div->mult = 1, + enh_fixed_div->div = 2, + enh_fixed_div->hw.init = &init; + + clk = devm_clk_register(dev, &enh_fixed_div->hw); + if (WARN_ON(IS_ERR(clk))) + return PTR_ERR(clk); + + enh_div = devm_kzalloc(dev, sizeof(*enh_div), GFP_KERNEL); + if (!enh_div) + return -ENOMEM; + + snprintf(name, sizeof(name), "%s#enh_div", dev_name(dev)); + init.name = name; + init.ops = &clk_divider_ops; + init.flags = CLK_SET_RATE_PARENT; + parent_data[0].hw = &enh_fixed_div->hw; + init.num_parents = 1; + + enh_div->shift = 16, + enh_div->width = 8, + enh_div->reg = spicc->base + SPICC_ENH_CTL0; + enh_div->hw.init = &init; + + clk = devm_clk_register(dev, &enh_div->hw); + if (WARN_ON(IS_ERR(clk))) + return PTR_ERR(clk); + + mux = devm_kzalloc(dev, sizeof(*mux), GFP_KERNEL); + if (!mux) + return -ENOMEM; + + snprintf(name, sizeof(name), "%s#sel", dev_name(dev)); + init.name = name; + init.ops = &clk_mux_ops; + parent_data[0].hw = &spicc->pow2_div.hw; + parent_data[1].hw = &enh_div->hw; + init.num_parents = 2; + init.flags = CLK_SET_RATE_PARENT; + + mux->mask = 0x1, + mux->shift = 24, + mux->reg = spicc->base + SPICC_ENH_CTL0; + mux->hw.init = &init; + + spicc->clk = devm_clk_register(dev, &mux->hw); + if (WARN_ON(IS_ERR(spicc->clk))) + return PTR_ERR(spicc->clk); + + return 0; +} + +static int meson_spicc_probe(struct platform_device *pdev) +{ + struct spi_master *master; + struct meson_spicc_device *spicc; + int ret, irq; + + master = spi_alloc_master(&pdev->dev, sizeof(*spicc)); + if (!master) { + dev_err(&pdev->dev, "master allocation failed\n"); + return -ENOMEM; + } + spicc = spi_master_get_devdata(master); + spicc->master = master; + + spicc->data = of_device_get_match_data(&pdev->dev); + if (!spicc->data) { + dev_err(&pdev->dev, "failed to get match data\n"); + ret = -EINVAL; + goto out_master; + } + + spicc->pdev = pdev; + platform_set_drvdata(pdev, spicc); + + init_completion(&spicc->done); + + spicc->base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(spicc->base)) { + dev_err(&pdev->dev, "io resource mapping failed\n"); + ret = PTR_ERR(spicc->base); + goto out_master; + } + + /* Set master mode and enable controller */ + writel_relaxed(SPICC_ENABLE | SPICC_MODE_MASTER, + spicc->base + SPICC_CONREG); + + /* Disable all IRQs */ + writel_relaxed(0, spicc->base + SPICC_INTREG); + + irq = platform_get_irq(pdev, 0); + if (irq < 0) { + ret = irq; + goto out_master; + } + + ret = devm_request_irq(&pdev->dev, irq, meson_spicc_irq, + 0, NULL, spicc); + if (ret) { + dev_err(&pdev->dev, "irq request failed\n"); + goto out_master; + } + + spicc->core = devm_clk_get(&pdev->dev, "core"); + if (IS_ERR(spicc->core)) { + dev_err(&pdev->dev, "core clock request failed\n"); + ret = PTR_ERR(spicc->core); + goto out_master; + } + + if (spicc->data->has_pclk) { + spicc->pclk = devm_clk_get(&pdev->dev, "pclk"); + if (IS_ERR(spicc->pclk)) { + dev_err(&pdev->dev, "pclk clock request failed\n"); + ret = PTR_ERR(spicc->pclk); + goto out_master; + } + } + + ret = clk_prepare_enable(spicc->core); + if (ret) { + dev_err(&pdev->dev, "core clock enable failed\n"); + goto out_master; + } + + ret = clk_prepare_enable(spicc->pclk); + if (ret) { + dev_err(&pdev->dev, "pclk clock enable failed\n"); + goto out_core_clk; + } + + device_reset_optional(&pdev->dev); + + master->num_chipselect = 4; + master->dev.of_node = pdev->dev.of_node; + master->mode_bits = SPI_CPHA | SPI_CPOL | SPI_CS_HIGH; + master->bits_per_word_mask = SPI_BPW_MASK(32) | + SPI_BPW_MASK(24) | + SPI_BPW_MASK(16) | + SPI_BPW_MASK(8); + master->flags = (SPI_MASTER_MUST_RX | SPI_MASTER_MUST_TX); + master->min_speed_hz = spicc->data->min_speed_hz; + master->max_speed_hz = spicc->data->max_speed_hz; + master->setup = meson_spicc_setup; + master->cleanup = meson_spicc_cleanup; + master->prepare_message = meson_spicc_prepare_message; + master->unprepare_transfer_hardware = meson_spicc_unprepare_transfer; + master->transfer_one = meson_spicc_transfer_one; + master->use_gpio_descriptors = true; + + meson_spicc_oen_enable(spicc); + + ret = meson_spicc_pow2_clk_init(spicc); + if (ret) { + dev_err(&pdev->dev, "pow2 clock registration failed\n"); + goto out_clk; + } + + if (spicc->data->has_enhance_clk_div) { + ret = meson_spicc_enh_clk_init(spicc); + if (ret) { + dev_err(&pdev->dev, "clock registration failed\n"); + goto out_clk; + } + } + + ret = devm_spi_register_master(&pdev->dev, master); + if (ret) { + dev_err(&pdev->dev, "spi master registration failed\n"); + goto out_clk; + } + + return 0; + +out_clk: + clk_disable_unprepare(spicc->pclk); + +out_core_clk: + clk_disable_unprepare(spicc->core); + +out_master: + spi_master_put(master); + + return ret; +} + +static int meson_spicc_remove(struct platform_device *pdev) +{ + struct meson_spicc_device *spicc = platform_get_drvdata(pdev); + + /* Disable SPI */ + writel(0, spicc->base + SPICC_CONREG); + + clk_disable_unprepare(spicc->core); + clk_disable_unprepare(spicc->pclk); + + spi_master_put(spicc->master); + + return 0; +} + +static const struct meson_spicc_data meson_spicc_gx_data = { + .max_speed_hz = 30000000, + .min_speed_hz = 325000, + .fifo_size = 16, +}; + +static const struct meson_spicc_data meson_spicc_axg_data = { + .max_speed_hz = 80000000, + .min_speed_hz = 325000, + .fifo_size = 16, + .has_oen = true, + .has_enhance_clk_div = true, +}; + +static const struct meson_spicc_data meson_spicc_g12a_data = { + .max_speed_hz = 166666666, + .min_speed_hz = 50000, + .fifo_size = 15, + .has_oen = true, + .has_enhance_clk_div = true, + .has_pclk = true, +}; + +static const struct of_device_id meson_spicc_of_match[] = { + { + .compatible = "amlogic,meson-gx-spicc", + .data = &meson_spicc_gx_data, + }, + { + .compatible = "amlogic,meson-axg-spicc", + .data = &meson_spicc_axg_data, + }, + { + .compatible = "amlogic,meson-g12a-spicc", + .data = &meson_spicc_g12a_data, + }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(of, meson_spicc_of_match); + +static struct platform_driver meson_spicc_driver = { + .probe = meson_spicc_probe, + .remove = meson_spicc_remove, + .driver = { + .name = "meson-spicc", + .of_match_table = of_match_ptr(meson_spicc_of_match), + }, +}; + +module_platform_driver(meson_spicc_driver); + +MODULE_DESCRIPTION("Meson SPI Communication Controller driver"); +MODULE_AUTHOR("Neil Armstrong <narmstrong@baylibre.com>"); +MODULE_LICENSE("GPL"); |