/* * SuperH MSIOF SPI Master Interface * * Copyright (c) 2009 Magnus Damm * Copyright (C) 2014 Glider bvba * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. * */ #include <linux/bitmap.h> #include <linux/clk.h> #include <linux/completion.h> #include <linux/delay.h> #include <linux/dma-mapping.h> #include <linux/dmaengine.h> #include <linux/err.h> #include <linux/gpio.h> #include <linux/interrupt.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/pm_runtime.h> #include <linux/sh_dma.h> #include <linux/spi/sh_msiof.h> #include <linux/spi/spi.h> #include <asm/unaligned.h> struct sh_msiof_chipdata { u16 tx_fifo_size; u16 rx_fifo_size; u16 master_flags; }; struct sh_msiof_spi_priv { struct spi_master *master; void __iomem *mapbase; struct clk *clk; struct platform_device *pdev; const struct sh_msiof_chipdata *chipdata; struct sh_msiof_spi_info *info; struct completion done; int tx_fifo_size; int rx_fifo_size; void *tx_dma_page; void *rx_dma_page; dma_addr_t tx_dma_addr; dma_addr_t rx_dma_addr; }; #define TMDR1 0x00 /* Transmit Mode Register 1 */ #define TMDR2 0x04 /* Transmit Mode Register 2 */ #define TMDR3 0x08 /* Transmit Mode Register 3 */ #define RMDR1 0x10 /* Receive Mode Register 1 */ #define RMDR2 0x14 /* Receive Mode Register 2 */ #define RMDR3 0x18 /* Receive Mode Register 3 */ #define TSCR 0x20 /* Transmit Clock Select Register */ #define RSCR 0x22 /* Receive Clock Select Register (SH, A1, APE6) */ #define CTR 0x28 /* Control Register */ #define FCTR 0x30 /* FIFO Control Register */ #define STR 0x40 /* Status Register */ #define IER 0x44 /* Interrupt Enable Register */ #define TDR1 0x48 /* Transmit Control Data Register 1 (SH, A1) */ #define TDR2 0x4c /* Transmit Control Data Register 2 (SH, A1) */ #define TFDR 0x50 /* Transmit FIFO Data Register */ #define RDR1 0x58 /* Receive Control Data Register 1 (SH, A1) */ #define RDR2 0x5c /* Receive Control Data Register 2 (SH, A1) */ #define RFDR 0x60 /* Receive FIFO Data Register */ /* TMDR1 and RMDR1 */ #define MDR1_TRMD 0x80000000 /* Transfer Mode (1 = Master mode) */ #define MDR1_SYNCMD_MASK 0x30000000 /* SYNC Mode */ #define MDR1_SYNCMD_SPI 0x20000000 /* Level mode/SPI */ #define MDR1_SYNCMD_LR 0x30000000 /* L/R mode */ #define MDR1_SYNCAC_SHIFT 25 /* Sync Polarity (1 = Active-low) */ #define MDR1_BITLSB_SHIFT 24 /* MSB/LSB First (1 = LSB first) */ #define MDR1_DTDL_SHIFT 20 /* Data Pin Bit Delay for MSIOF_SYNC */ #define MDR1_SYNCDL_SHIFT 16 /* Frame Sync Signal Timing Delay */ #define MDR1_FLD_MASK 0x0000000c /* Frame Sync Signal Interval (0-3) */ #define MDR1_FLD_SHIFT 2 #define MDR1_XXSTP 0x00000001 /* Transmission/Reception Stop on FIFO */ /* TMDR1 */ #define TMDR1_PCON 0x40000000 /* Transfer Signal Connection */ /* TMDR2 and RMDR2 */ #define MDR2_BITLEN1(i) (((i) - 1) << 24) /* Data Size (8-32 bits) */ #define MDR2_WDLEN1(i) (((i) - 1) << 16) /* Word Count (1-64/256 (SH, A1))) */ #define MDR2_GRPMASK1 0x00000001 /* Group Output Mask 1 (SH, A1) */ #define MAX_WDLEN 256U /* TSCR and RSCR */ #define SCR_BRPS_MASK 0x1f00 /* Prescaler Setting (1-32) */ #define SCR_BRPS(i) (((i) - 1) << 8) #define SCR_BRDV_MASK 0x0007 /* Baud Rate Generator's Division Ratio */ #define SCR_BRDV_DIV_2 0x0000 #define SCR_BRDV_DIV_4 0x0001 #define SCR_BRDV_DIV_8 0x0002 #define SCR_BRDV_DIV_16 0x0003 #define SCR_BRDV_DIV_32 0x0004 #define SCR_BRDV_DIV_1 0x0007 /* CTR */ #define CTR_TSCKIZ_MASK 0xc0000000 /* Transmit Clock I/O Polarity Select */ #define CTR_TSCKIZ_SCK 0x80000000 /* Disable SCK when TX disabled */ #define CTR_TSCKIZ_POL_SHIFT 30 /* Transmit Clock Polarity */ #define CTR_RSCKIZ_MASK 0x30000000 /* Receive Clock Polarity Select */ #define CTR_RSCKIZ_SCK 0x20000000 /* Must match CTR_TSCKIZ_SCK */ #define CTR_RSCKIZ_POL_SHIFT 28 /* Receive Clock Polarity */ #define CTR_TEDG_SHIFT 27 /* Transmit Timing (1 = falling edge) */ #define CTR_REDG_SHIFT 26 /* Receive Timing (1 = falling edge) */ #define CTR_TXDIZ_MASK 0x00c00000 /* Pin Output When TX is Disabled */ #define CTR_TXDIZ_LOW 0x00000000 /* 0 */ #define CTR_TXDIZ_HIGH 0x00400000 /* 1 */ #define CTR_TXDIZ_HIZ 0x00800000 /* High-impedance */ #define CTR_TSCKE 0x00008000 /* Transmit Serial Clock Output Enable */ #define CTR_TFSE 0x00004000 /* Transmit Frame Sync Signal Output Enable */ #define CTR_TXE 0x00000200 /* Transmit Enable */ #define CTR_RXE 0x00000100 /* Receive Enable */ /* FCTR */ #define FCTR_TFWM_MASK 0xe0000000 /* Transmit FIFO Watermark */ #define FCTR_TFWM_64 0x00000000 /* Transfer Request when 64 empty stages */ #define FCTR_TFWM_32 0x20000000 /* Transfer Request when 32 empty stages */ #define FCTR_TFWM_24 0x40000000 /* Transfer Request when 24 empty stages */ #define FCTR_TFWM_16 0x60000000 /* Transfer Request when 16 empty stages */ #define FCTR_TFWM_12 0x80000000 /* Transfer Request when 12 empty stages */ #define FCTR_TFWM_8 0xa0000000 /* Transfer Request when 8 empty stages */ #define FCTR_TFWM_4 0xc0000000 /* Transfer Request when 4 empty stages */ #define FCTR_TFWM_1 0xe0000000 /* Transfer Request when 1 empty stage */ #define FCTR_TFUA_MASK 0x07f00000 /* Transmit FIFO Usable Area */ #define FCTR_TFUA_SHIFT 20 #define FCTR_TFUA(i) ((i) << FCTR_TFUA_SHIFT) #define FCTR_RFWM_MASK 0x0000e000 /* Receive FIFO Watermark */ #define FCTR_RFWM_1 0x00000000 /* Transfer Request when 1 valid stages */ #define FCTR_RFWM_4 0x00002000 /* Transfer Request when 4 valid stages */ #define FCTR_RFWM_8 0x00004000 /* Transfer Request when 8 valid stages */ #define FCTR_RFWM_16 0x00006000 /* Transfer Request when 16 valid stages */ #define FCTR_RFWM_32 0x00008000 /* Transfer Request when 32 valid stages */ #define FCTR_RFWM_64 0x0000a000 /* Transfer Request when 64 valid stages */ #define FCTR_RFWM_128 0x0000c000 /* Transfer Request when 128 valid stages */ #define FCTR_RFWM_256 0x0000e000 /* Transfer Request when 256 valid stages */ #define FCTR_RFUA_MASK 0x00001ff0 /* Receive FIFO Usable Area (0x40 = full) */ #define FCTR_RFUA_SHIFT 4 #define FCTR_RFUA(i) ((i) << FCTR_RFUA_SHIFT) /* STR */ #define STR_TFEMP 0x20000000 /* Transmit FIFO Empty */ #define STR_TDREQ 0x10000000 /* Transmit Data Transfer Request */ #define STR_TEOF 0x00800000 /* Frame Transmission End */ #define STR_TFSERR 0x00200000 /* Transmit Frame Synchronization Error */ #define STR_TFOVF 0x00100000 /* Transmit FIFO Overflow */ #define STR_TFUDF 0x00080000 /* Transmit FIFO Underflow */ #define STR_RFFUL 0x00002000 /* Receive FIFO Full */ #define STR_RDREQ 0x00001000 /* Receive Data Transfer Request */ #define STR_REOF 0x00000080 /* Frame Reception End */ #define STR_RFSERR 0x00000020 /* Receive Frame Synchronization Error */ #define STR_RFUDF 0x00000010 /* Receive FIFO Underflow */ #define STR_RFOVF 0x00000008 /* Receive FIFO Overflow */ /* IER */ #define IER_TDMAE 0x80000000 /* Transmit Data DMA Transfer Req. Enable */ #define IER_TFEMPE 0x20000000 /* Transmit FIFO Empty Enable */ #define IER_TDREQE 0x10000000 /* Transmit Data Transfer Request Enable */ #define IER_TEOFE 0x00800000 /* Frame Transmission End Enable */ #define IER_TFSERRE 0x00200000 /* Transmit Frame Sync Error Enable */ #define IER_TFOVFE 0x00100000 /* Transmit FIFO Overflow Enable */ #define IER_TFUDFE 0x00080000 /* Transmit FIFO Underflow Enable */ #define IER_RDMAE 0x00008000 /* Receive Data DMA Transfer Req. Enable */ #define IER_RFFULE 0x00002000 /* Receive FIFO Full Enable */ #define IER_RDREQE 0x00001000 /* Receive Data Transfer Request Enable */ #define IER_REOFE 0x00000080 /* Frame Reception End Enable */ #define IER_RFSERRE 0x00000020 /* Receive Frame Sync Error Enable */ #define IER_RFUDFE 0x00000010 /* Receive FIFO Underflow Enable */ #define IER_RFOVFE 0x00000008 /* Receive FIFO Overflow Enable */ static u32 sh_msiof_read(struct sh_msiof_spi_priv *p, int reg_offs) { switch (reg_offs) { case TSCR: case RSCR: return ioread16(p->mapbase + reg_offs); default: return ioread32(p->mapbase + reg_offs); } } static void sh_msiof_write(struct sh_msiof_spi_priv *p, int reg_offs, u32 value) { switch (reg_offs) { case TSCR: case RSCR: iowrite16(value, p->mapbase + reg_offs); break; default: iowrite32(value, p->mapbase + reg_offs); break; } } static int sh_msiof_modify_ctr_wait(struct sh_msiof_spi_priv *p, u32 clr, u32 set) { u32 mask = clr | set; u32 data; int k; data = sh_msiof_read(p, CTR); data &= ~clr; data |= set; sh_msiof_write(p, CTR, data); for (k = 100; k > 0; k--) { if ((sh_msiof_read(p, CTR) & mask) == set) break; udelay(10); } return k > 0 ? 0 : -ETIMEDOUT; } static irqreturn_t sh_msiof_spi_irq(int irq, void *data) { struct sh_msiof_spi_priv *p = data; /* just disable the interrupt and wake up */ sh_msiof_write(p, IER, 0); complete(&p->done); return IRQ_HANDLED; } static struct { unsigned short div; unsigned short brdv; } const sh_msiof_spi_div_table[] = { { 1, SCR_BRDV_DIV_1 }, { 2, SCR_BRDV_DIV_2 }, { 4, SCR_BRDV_DIV_4 }, { 8, SCR_BRDV_DIV_8 }, { 16, SCR_BRDV_DIV_16 }, { 32, SCR_BRDV_DIV_32 }, }; static void sh_msiof_spi_set_clk_regs(struct sh_msiof_spi_priv *p, unsigned long parent_rate, u32 spi_hz) { unsigned long div = 1024; u32 brps, scr; size_t k; if (!WARN_ON(!spi_hz || !parent_rate)) div = DIV_ROUND_UP(parent_rate, spi_hz); for (k = 0; k < ARRAY_SIZE(sh_msiof_spi_div_table); k++) { brps = DIV_ROUND_UP(div, sh_msiof_spi_div_table[k].div); if (brps <= 32) /* max of brdv is 32 */ break; } k = min_t(int, k, ARRAY_SIZE(sh_msiof_spi_div_table) - 1); scr = sh_msiof_spi_div_table[k].brdv | SCR_BRPS(brps); sh_msiof_write(p, TSCR, scr); if (!(p->chipdata->master_flags & SPI_MASTER_MUST_TX)) sh_msiof_write(p, RSCR, scr); } static u32 sh_msiof_get_delay_bit(u32 dtdl_or_syncdl) { /* * DTDL/SYNCDL bit : p->info->dtdl or p->info->syncdl * b'000 : 0 * b'001 : 100 * b'010 : 200 * b'011 (SYNCDL only) : 300 * b'101 : 50 * b'110 : 150 */ if (dtdl_or_syncdl % 100) return dtdl_or_syncdl / 100 + 5; else return dtdl_or_syncdl / 100; } static u32 sh_msiof_spi_get_dtdl_and_syncdl(struct sh_msiof_spi_priv *p) { u32 val; if (!p->info) return 0; /* check if DTDL and SYNCDL is allowed value */ if (p->info->dtdl > 200 || p->info->syncdl > 300) { dev_warn(&p->pdev->dev, "DTDL or SYNCDL is too large\n"); return 0; } /* check if the sum of DTDL and SYNCDL becomes an integer value */ if ((p->info->dtdl + p->info->syncdl) % 100) { dev_warn(&p->pdev->dev, "the sum of DTDL/SYNCDL is not good\n"); return 0; } val = sh_msiof_get_delay_bit(p->info->dtdl) << MDR1_DTDL_SHIFT; val |= sh_msiof_get_delay_bit(p->info->syncdl) << MDR1_SYNCDL_SHIFT; return val; } static void sh_msiof_spi_set_pin_regs(struct sh_msiof_spi_priv *p, u32 cpol, u32 cpha, u32 tx_hi_z, u32 lsb_first, u32 cs_high) { u32 tmp; int edge; /* * CPOL CPHA TSCKIZ RSCKIZ TEDG REDG * 0 0 10 10 1 1 * 0 1 10 10 0 0 * 1 0 11 11 0 0 * 1 1 11 11 1 1 */ tmp = MDR1_SYNCMD_SPI | 1 << MDR1_FLD_SHIFT | MDR1_XXSTP; tmp |= !cs_high << MDR1_SYNCAC_SHIFT; tmp |= lsb_first << MDR1_BITLSB_SHIFT; tmp |= sh_msiof_spi_get_dtdl_and_syncdl(p); sh_msiof_write(p, TMDR1, tmp | MDR1_TRMD | TMDR1_PCON); if (p->chipdata->master_flags & SPI_MASTER_MUST_TX) { /* These bits are reserved if RX needs TX */ tmp &= ~0x0000ffff; } sh_msiof_write(p, RMDR1, tmp); tmp = 0; tmp |= CTR_TSCKIZ_SCK | cpol << CTR_TSCKIZ_POL_SHIFT; tmp |= CTR_RSCKIZ_SCK | cpol << CTR_RSCKIZ_POL_SHIFT; edge = cpol ^ !cpha; tmp |= edge << CTR_TEDG_SHIFT; tmp |= edge << CTR_REDG_SHIFT; tmp |= tx_hi_z ? CTR_TXDIZ_HIZ : CTR_TXDIZ_LOW; sh_msiof_write(p, CTR, tmp); } static void sh_msiof_spi_set_mode_regs(struct sh_msiof_spi_priv *p, const void *tx_buf, void *rx_buf, u32 bits, u32 words) { u32 dr2 = MDR2_BITLEN1(bits) | MDR2_WDLEN1(words); if (tx_buf || (p->chipdata->master_flags & SPI_MASTER_MUST_TX)) sh_msiof_write(p, TMDR2, dr2); else sh_msiof_write(p, TMDR2, dr2 | MDR2_GRPMASK1); if (rx_buf) sh_msiof_write(p, RMDR2, dr2); } static void sh_msiof_reset_str(struct sh_msiof_spi_priv *p) { sh_msiof_write(p, STR, sh_msiof_read(p, STR)); } static void sh_msiof_spi_write_fifo_8(struct sh_msiof_spi_priv *p, const void *tx_buf, int words, int fs) { const u8 *buf_8 = tx_buf; int k; for (k = 0; k < words; k++) sh_msiof_write(p, TFDR, buf_8[k] << fs); } static void sh_msiof_spi_write_fifo_16(struct sh_msiof_spi_priv *p, const void *tx_buf, int words, int fs) { const u16 *buf_16 = tx_buf; int k; for (k = 0; k < words; k++) sh_msiof_write(p, TFDR, buf_16[k] << fs); } static void sh_msiof_spi_write_fifo_16u(struct sh_msiof_spi_priv *p, const void *tx_buf, int words, int fs) { const u16 *buf_16 = tx_buf; int k; for (k = 0; k < words; k++) sh_msiof_write(p, TFDR, get_unaligned(&buf_16[k]) << fs); } static void sh_msiof_spi_write_fifo_32(struct sh_msiof_spi_priv *p, const void *tx_buf, int words, int fs) { const u32 *buf_32 = tx_buf; int k; for (k = 0; k < words; k++) sh_msiof_write(p, TFDR, buf_32[k] << fs); } static void sh_msiof_spi_write_fifo_32u(struct sh_msiof_spi_priv *p, const void *tx_buf, int words, int fs) { const u32 *buf_32 = tx_buf; int k; for (k = 0; k < words; k++) sh_msiof_write(p, TFDR, get_unaligned(&buf_32[k]) << fs); } static void sh_msiof_spi_write_fifo_s32(struct sh_msiof_spi_priv *p, const void *tx_buf, int words, int fs) { const u32 *buf_32 = tx_buf; int k; for (k = 0; k < words; k++) sh_msiof_write(p, TFDR, swab32(buf_32[k] << fs)); } static void sh_msiof_spi_write_fifo_s32u(struct sh_msiof_spi_priv *p, const void *tx_buf, int words, int fs) { const u32 *buf_32 = tx_buf; int k; for (k = 0; k < words; k++) sh_msiof_write(p, TFDR, swab32(get_unaligned(&buf_32[k]) << fs)); } static void sh_msiof_spi_read_fifo_8(struct sh_msiof_spi_priv *p, void *rx_buf, int words, int fs) { u8 *buf_8 = rx_buf; int k; for (k = 0; k < words; k++) buf_8[k] = sh_msiof_read(p, RFDR) >> fs; } static void sh_msiof_spi_read_fifo_16(struct sh_msiof_spi_priv *p, void *rx_buf, int words, int fs) { u16 *buf_16 = rx_buf; int k; for (k = 0; k < words; k++) buf_16[k] = sh_msiof_read(p, RFDR) >> fs; } static void sh_msiof_spi_read_fifo_16u(struct sh_msiof_spi_priv *p, void *rx_buf, int words, int fs) { u16 *buf_16 = rx_buf; int k; for (k = 0; k < words; k++) put_unaligned(sh_msiof_read(p, RFDR) >> fs, &buf_16[k]); } static void sh_msiof_spi_read_fifo_32(struct sh_msiof_spi_priv *p, void *rx_buf, int words, int fs) { u32 *buf_32 = rx_buf; int k; for (k = 0; k < words; k++) buf_32[k] = sh_msiof_read(p, RFDR) >> fs; } static void sh_msiof_spi_read_fifo_32u(struct sh_msiof_spi_priv *p, void *rx_buf, int words, int fs) { u32 *buf_32 = rx_buf; int k; for (k = 0; k < words; k++) put_unaligned(sh_msiof_read(p, RFDR) >> fs, &buf_32[k]); } static void sh_msiof_spi_read_fifo_s32(struct sh_msiof_spi_priv *p, void *rx_buf, int words, int fs) { u32 *buf_32 = rx_buf; int k; for (k = 0; k < words; k++) buf_32[k] = swab32(sh_msiof_read(p, RFDR) >> fs); } static void sh_msiof_spi_read_fifo_s32u(struct sh_msiof_spi_priv *p, void *rx_buf, int words, int fs) { u32 *buf_32 = rx_buf; int k; for (k = 0; k < words; k++) put_unaligned(swab32(sh_msiof_read(p, RFDR) >> fs), &buf_32[k]); } static int sh_msiof_spi_setup(struct spi_device *spi) { struct device_node *np = spi->master->dev.of_node; struct sh_msiof_spi_priv *p = spi_master_get_devdata(spi->master); pm_runtime_get_sync(&p->pdev->dev); if (!np) { /* * Use spi->controller_data for CS (same strategy as spi_gpio), * if any. otherwise let HW control CS */ spi->cs_gpio = (uintptr_t)spi->controller_data; } /* Configure pins before deasserting CS */ sh_msiof_spi_set_pin_regs(p, !!(spi->mode & SPI_CPOL), !!(spi->mode & SPI_CPHA), !!(spi->mode & SPI_3WIRE), !!(spi->mode & SPI_LSB_FIRST), !!(spi->mode & SPI_CS_HIGH)); if (spi->cs_gpio >= 0) gpio_set_value(spi->cs_gpio, !(spi->mode & SPI_CS_HIGH)); pm_runtime_put(&p->pdev->dev); return 0; } static int sh_msiof_prepare_message(struct spi_master *master, struct spi_message *msg) { struct sh_msiof_spi_priv *p = spi_master_get_devdata(master); const struct spi_device *spi = msg->spi; /* Configure pins before asserting CS */ sh_msiof_spi_set_pin_regs(p, !!(spi->mode & SPI_CPOL), !!(spi->mode & SPI_CPHA), !!(spi->mode & SPI_3WIRE), !!(spi->mode & SPI_LSB_FIRST), !!(spi->mode & SPI_CS_HIGH)); return 0; } static int sh_msiof_spi_start(struct sh_msiof_spi_priv *p, void *rx_buf) { int ret; /* setup clock and rx/tx signals */ ret = sh_msiof_modify_ctr_wait(p, 0, CTR_TSCKE); if (rx_buf && !ret) ret = sh_msiof_modify_ctr_wait(p, 0, CTR_RXE); if (!ret) ret = sh_msiof_modify_ctr_wait(p, 0, CTR_TXE); /* start by setting frame bit */ if (!ret) ret = sh_msiof_modify_ctr_wait(p, 0, CTR_TFSE); return ret; } static int sh_msiof_spi_stop(struct sh_msiof_spi_priv *p, void *rx_buf) { int ret; /* shut down frame, rx/tx and clock signals */ ret = sh_msiof_modify_ctr_wait(p, CTR_TFSE, 0); if (!ret) ret = sh_msiof_modify_ctr_wait(p, CTR_TXE, 0); if (rx_buf && !ret) ret = sh_msiof_modify_ctr_wait(p, CTR_RXE, 0); if (!ret) ret = sh_msiof_modify_ctr_wait(p, CTR_TSCKE, 0); return ret; } static int sh_msiof_spi_txrx_once(struct sh_msiof_spi_priv *p, void (*tx_fifo)(struct sh_msiof_spi_priv *, const void *, int, int), void (*rx_fifo)(struct sh_msiof_spi_priv *, void *, int, int), const void *tx_buf, void *rx_buf, int words, int bits) { int fifo_shift; int ret; /* limit maximum word transfer to rx/tx fifo size */ if (tx_buf) words = min_t(int, words, p->tx_fifo_size); if (rx_buf) words = min_t(int, words, p->rx_fifo_size); /* the fifo contents need shifting */ fifo_shift = 32 - bits; /* default FIFO watermarks for PIO */ sh_msiof_write(p, FCTR, 0); /* setup msiof transfer mode registers */ sh_msiof_spi_set_mode_regs(p, tx_buf, rx_buf, bits, words); sh_msiof_write(p, IER, IER_TEOFE | IER_REOFE); /* write tx fifo */ if (tx_buf) tx_fifo(p, tx_buf, words, fifo_shift); reinit_completion(&p->done); ret = sh_msiof_spi_start(p, rx_buf); if (ret) { dev_err(&p->pdev->dev, "failed to start hardware\n"); goto stop_ier; } /* wait for tx fifo to be emptied / rx fifo to be filled */ if (!wait_for_completion_timeout(&p->done, HZ)) { dev_err(&p->pdev->dev, "PIO timeout\n"); ret = -ETIMEDOUT; goto stop_reset; } /* read rx fifo */ if (rx_buf) rx_fifo(p, rx_buf, words, fifo_shift); /* clear status bits */ sh_msiof_reset_str(p); ret = sh_msiof_spi_stop(p, rx_buf); if (ret) { dev_err(&p->pdev->dev, "failed to shut down hardware\n"); return ret; } return words; stop_reset: sh_msiof_reset_str(p); sh_msiof_spi_stop(p, rx_buf); stop_ier: sh_msiof_write(p, IER, 0); return ret; } static void sh_msiof_dma_complete(void *arg) { struct sh_msiof_spi_priv *p = arg; sh_msiof_write(p, IER, 0); complete(&p->done); } static int sh_msiof_dma_once(struct sh_msiof_spi_priv *p, const void *tx, void *rx, unsigned int len) { u32 ier_bits = 0; struct dma_async_tx_descriptor *desc_tx = NULL, *desc_rx = NULL; dma_cookie_t cookie; int ret; /* First prepare and submit the DMA request(s), as this may fail */ if (rx) { ier_bits |= IER_RDREQE | IER_RDMAE; desc_rx = dmaengine_prep_slave_single(p->master->dma_rx, p->rx_dma_addr, len, DMA_FROM_DEVICE, DMA_PREP_INTERRUPT | DMA_CTRL_ACK); if (!desc_rx) return -EAGAIN; desc_rx->callback = sh_msiof_dma_complete; desc_rx->callback_param = p; cookie = dmaengine_submit(desc_rx); if (dma_submit_error(cookie)) return cookie; } if (tx) { ier_bits |= IER_TDREQE | IER_TDMAE; dma_sync_single_for_device(p->master->dma_tx->device->dev, p->tx_dma_addr, len, DMA_TO_DEVICE); desc_tx = dmaengine_prep_slave_single(p->master->dma_tx, p->tx_dma_addr, len, DMA_TO_DEVICE, DMA_PREP_INTERRUPT | DMA_CTRL_ACK); if (!desc_tx) { ret = -EAGAIN; goto no_dma_tx; } if (rx) { /* No callback */ desc_tx->callback = NULL; } else { desc_tx->callback = sh_msiof_dma_complete; desc_tx->callback_param = p; } cookie = dmaengine_submit(desc_tx); if (dma_submit_error(cookie)) { ret = cookie; goto no_dma_tx; } } /* 1 stage FIFO watermarks for DMA */ sh_msiof_write(p, FCTR, FCTR_TFWM_1 | FCTR_RFWM_1); /* setup msiof transfer mode registers (32-bit words) */ sh_msiof_spi_set_mode_regs(p, tx, rx, 32, len / 4); sh_msiof_write(p, IER, ier_bits); reinit_completion(&p->done); /* Now start DMA */ if (rx) dma_async_issue_pending(p->master->dma_rx); if (tx) dma_async_issue_pending(p->master->dma_tx); ret = sh_msiof_spi_start(p, rx); if (ret) { dev_err(&p->pdev->dev, "failed to start hardware\n"); goto stop_dma; } /* wait for tx fifo to be emptied / rx fifo to be filled */ if (!wait_for_completion_timeout(&p->done, HZ)) { dev_err(&p->pdev->dev, "DMA timeout\n"); ret = -ETIMEDOUT; goto stop_reset; } /* clear status bits */ sh_msiof_reset_str(p); ret = sh_msiof_spi_stop(p, rx); if (ret) { dev_err(&p->pdev->dev, "failed to shut down hardware\n"); return ret; } if (rx) dma_sync_single_for_cpu(p->master->dma_rx->device->dev, p->rx_dma_addr, len, DMA_FROM_DEVICE); return 0; stop_reset: sh_msiof_reset_str(p); sh_msiof_spi_stop(p, rx); stop_dma: if (tx) dmaengine_terminate_all(p->master->dma_tx); no_dma_tx: if (rx) dmaengine_terminate_all(p->master->dma_rx); sh_msiof_write(p, IER, 0); return ret; } static void copy_bswap32(u32 *dst, const u32 *src, unsigned int words) { /* src or dst can be unaligned, but not both */ if ((unsigned long)src & 3) { while (words--) { *dst++ = swab32(get_unaligned(src)); src++; } } else if ((unsigned long)dst & 3) { while (words--) { put_unaligned(swab32(*src++), dst); dst++; } } else { while (words--) *dst++ = swab32(*src++); } } static void copy_wswap32(u32 *dst, const u32 *src, unsigned int words) { /* src or dst can be unaligned, but not both */ if ((unsigned long)src & 3) { while (words--) { *dst++ = swahw32(get_unaligned(src)); src++; } } else if ((unsigned long)dst & 3) { while (words--) { put_unaligned(swahw32(*src++), dst); dst++; } } else { while (words--) *dst++ = swahw32(*src++); } } static void copy_plain32(u32 *dst, const u32 *src, unsigned int words) { memcpy(dst, src, words * 4); } static int sh_msiof_transfer_one(struct spi_master *master, struct spi_device *spi, struct spi_transfer *t) { struct sh_msiof_spi_priv *p = spi_master_get_devdata(master); void (*copy32)(u32 *, const u32 *, unsigned int); void (*tx_fifo)(struct sh_msiof_spi_priv *, const void *, int, int); void (*rx_fifo)(struct sh_msiof_spi_priv *, void *, int, int); const void *tx_buf = t->tx_buf; void *rx_buf = t->rx_buf; unsigned int len = t->len; unsigned int bits = t->bits_per_word; unsigned int bytes_per_word; unsigned int words; int n; bool swab; int ret; /* setup clocks (clock already enabled in chipselect()) */ sh_msiof_spi_set_clk_regs(p, clk_get_rate(p->clk), t->speed_hz); while (master->dma_tx && len > 15) { /* * DMA supports 32-bit words only, hence pack 8-bit and 16-bit * words, with byte resp. word swapping. */ unsigned int l = min(len, MAX_WDLEN * 4); if (bits <= 8) { if (l & 3) break; copy32 = copy_bswap32; } else if (bits <= 16) { if (l & 1) break; copy32 = copy_wswap32; } else { copy32 = copy_plain32; } if (tx_buf) copy32(p->tx_dma_page, tx_buf, l / 4); ret = sh_msiof_dma_once(p, tx_buf, rx_buf, l); if (ret == -EAGAIN) { pr_warn_once("%s %s: DMA not available, falling back to PIO\n", dev_driver_string(&p->pdev->dev), dev_name(&p->pdev->dev)); break; } if (ret) return ret; if (rx_buf) { copy32(rx_buf, p->rx_dma_page, l / 4); rx_buf += l; } if (tx_buf) tx_buf += l; len -= l; if (!len) return 0; } if (bits <= 8 && len > 15 && !(len & 3)) { bits = 32; swab = true; } else { swab = false; } /* setup bytes per word and fifo read/write functions */ if (bits <= 8) { bytes_per_word = 1; tx_fifo = sh_msiof_spi_write_fifo_8; rx_fifo = sh_msiof_spi_read_fifo_8; } else if (bits <= 16) { bytes_per_word = 2; if ((unsigned long)tx_buf & 0x01) tx_fifo = sh_msiof_spi_write_fifo_16u; else tx_fifo = sh_msiof_spi_write_fifo_16; if ((unsigned long)rx_buf & 0x01) rx_fifo = sh_msiof_spi_read_fifo_16u; else rx_fifo = sh_msiof_spi_read_fifo_16; } else if (swab) { bytes_per_word = 4; if ((unsigned long)tx_buf & 0x03) tx_fifo = sh_msiof_spi_write_fifo_s32u; else tx_fifo = sh_msiof_spi_write_fifo_s32; if ((unsigned long)rx_buf & 0x03) rx_fifo = sh_msiof_spi_read_fifo_s32u; else rx_fifo = sh_msiof_spi_read_fifo_s32; } else { bytes_per_word = 4; if ((unsigned long)tx_buf & 0x03) tx_fifo = sh_msiof_spi_write_fifo_32u; else tx_fifo = sh_msiof_spi_write_fifo_32; if ((unsigned long)rx_buf & 0x03) rx_fifo = sh_msiof_spi_read_fifo_32u; else rx_fifo = sh_msiof_spi_read_fifo_32; } /* transfer in fifo sized chunks */ words = len / bytes_per_word; while (words > 0) { n = sh_msiof_spi_txrx_once(p, tx_fifo, rx_fifo, tx_buf, rx_buf, words, bits); if (n < 0) return n; if (tx_buf) tx_buf += n * bytes_per_word; if (rx_buf) rx_buf += n * bytes_per_word; words -= n; } return 0; } static const struct sh_msiof_chipdata sh_data = { .tx_fifo_size = 64, .rx_fifo_size = 64, .master_flags = 0, }; static const struct sh_msiof_chipdata r8a779x_data = { .tx_fifo_size = 64, .rx_fifo_size = 256, .master_flags = SPI_MASTER_MUST_TX, }; static const struct of_device_id sh_msiof_match[] = { { .compatible = "renesas,sh-msiof", .data = &sh_data }, { .compatible = "renesas,sh-mobile-msiof", .data = &sh_data }, { .compatible = "renesas,msiof-r8a7790", .data = &r8a779x_data }, { .compatible = "renesas,msiof-r8a7791", .data = &r8a779x_data }, { .compatible = "renesas,msiof-r8a7792", .data = &r8a779x_data }, { .compatible = "renesas,msiof-r8a7793", .data = &r8a779x_data }, { .compatible = "renesas,msiof-r8a7794", .data = &r8a779x_data }, {}, }; MODULE_DEVICE_TABLE(of, sh_msiof_match); #ifdef CONFIG_OF static struct sh_msiof_spi_info *sh_msiof_spi_parse_dt(struct device *dev) { struct sh_msiof_spi_info *info; struct device_node *np = dev->of_node; u32 num_cs = 1; info = devm_kzalloc(dev, sizeof(struct sh_msiof_spi_info), GFP_KERNEL); if (!info) return NULL; /* Parse the MSIOF properties */ of_property_read_u32(np, "num-cs", &num_cs); of_property_read_u32(np, "renesas,tx-fifo-size", &info->tx_fifo_override); of_property_read_u32(np, "renesas,rx-fifo-size", &info->rx_fifo_override); of_property_read_u32(np, "renesas,dtdl", &info->dtdl); of_property_read_u32(np, "renesas,syncdl", &info->syncdl); info->num_chipselect = num_cs; return info; } #else static struct sh_msiof_spi_info *sh_msiof_spi_parse_dt(struct device *dev) { return NULL; } #endif static struct dma_chan *sh_msiof_request_dma_chan(struct device *dev, enum dma_transfer_direction dir, unsigned int id, dma_addr_t port_addr) { dma_cap_mask_t mask; struct dma_chan *chan; struct dma_slave_config cfg; int ret; dma_cap_zero(mask); dma_cap_set(DMA_SLAVE, mask); chan = dma_request_slave_channel_compat(mask, shdma_chan_filter, (void *)(unsigned long)id, dev, dir == DMA_MEM_TO_DEV ? "tx" : "rx"); if (!chan) { dev_warn(dev, "dma_request_slave_channel_compat failed\n"); return NULL; } memset(&cfg, 0, sizeof(cfg)); cfg.direction = dir; if (dir == DMA_MEM_TO_DEV) { cfg.dst_addr = port_addr; cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; } else { cfg.src_addr = port_addr; cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; } ret = dmaengine_slave_config(chan, &cfg); if (ret) { dev_warn(dev, "dmaengine_slave_config failed %d\n", ret); dma_release_channel(chan); return NULL; } return chan; } static int sh_msiof_request_dma(struct sh_msiof_spi_priv *p) { struct platform_device *pdev = p->pdev; struct device *dev = &pdev->dev; const struct sh_msiof_spi_info *info = dev_get_platdata(dev); unsigned int dma_tx_id, dma_rx_id; const struct resource *res; struct spi_master *master; struct device *tx_dev, *rx_dev; if (dev->of_node) { /* In the OF case we will get the slave IDs from the DT */ dma_tx_id = 0; dma_rx_id = 0; } else if (info && info->dma_tx_id && info->dma_rx_id) { dma_tx_id = info->dma_tx_id; dma_rx_id = info->dma_rx_id; } else { /* The driver assumes no error */ return 0; } /* The DMA engine uses the second register set, if present */ res = platform_get_resource(pdev, IORESOURCE_MEM, 1); if (!res) res = platform_get_resource(pdev, IORESOURCE_MEM, 0); master = p->master; master->dma_tx = sh_msiof_request_dma_chan(dev, DMA_MEM_TO_DEV, dma_tx_id, res->start + TFDR); if (!master->dma_tx) return -ENODEV; master->dma_rx = sh_msiof_request_dma_chan(dev, DMA_DEV_TO_MEM, dma_rx_id, res->start + RFDR); if (!master->dma_rx) goto free_tx_chan; p->tx_dma_page = (void *)__get_free_page(GFP_KERNEL | GFP_DMA); if (!p->tx_dma_page) goto free_rx_chan; p->rx_dma_page = (void *)__get_free_page(GFP_KERNEL | GFP_DMA); if (!p->rx_dma_page) goto free_tx_page; tx_dev = master->dma_tx->device->dev; p->tx_dma_addr = dma_map_single(tx_dev, p->tx_dma_page, PAGE_SIZE, DMA_TO_DEVICE); if (dma_mapping_error(tx_dev, p->tx_dma_addr)) goto free_rx_page; rx_dev = master->dma_rx->device->dev; p->rx_dma_addr = dma_map_single(rx_dev, p->rx_dma_page, PAGE_SIZE, DMA_FROM_DEVICE); if (dma_mapping_error(rx_dev, p->rx_dma_addr)) goto unmap_tx_page; dev_info(dev, "DMA available"); return 0; unmap_tx_page: dma_unmap_single(tx_dev, p->tx_dma_addr, PAGE_SIZE, DMA_TO_DEVICE); free_rx_page: free_page((unsigned long)p->rx_dma_page); free_tx_page: free_page((unsigned long)p->tx_dma_page); free_rx_chan: dma_release_channel(master->dma_rx); free_tx_chan: dma_release_channel(master->dma_tx); master->dma_tx = NULL; return -ENODEV; } static void sh_msiof_release_dma(struct sh_msiof_spi_priv *p) { struct spi_master *master = p->master; struct device *dev; if (!master->dma_tx) return; dev = &p->pdev->dev; dma_unmap_single(master->dma_rx->device->dev, p->rx_dma_addr, PAGE_SIZE, DMA_FROM_DEVICE); dma_unmap_single(master->dma_tx->device->dev, p->tx_dma_addr, PAGE_SIZE, DMA_TO_DEVICE); free_page((unsigned long)p->rx_dma_page); free_page((unsigned long)p->tx_dma_page); dma_release_channel(master->dma_rx); dma_release_channel(master->dma_tx); } static int sh_msiof_spi_probe(struct platform_device *pdev) { struct resource *r; struct spi_master *master; const struct of_device_id *of_id; struct sh_msiof_spi_priv *p; int i; int ret; master = spi_alloc_master(&pdev->dev, sizeof(struct sh_msiof_spi_priv)); if (master == NULL) { dev_err(&pdev->dev, "failed to allocate spi master\n"); return -ENOMEM; } p = spi_master_get_devdata(master); platform_set_drvdata(pdev, p); p->master = master; of_id = of_match_device(sh_msiof_match, &pdev->dev); if (of_id) { p->chipdata = of_id->data; p->info = sh_msiof_spi_parse_dt(&pdev->dev); } else { p->chipdata = (const void *)pdev->id_entry->driver_data; p->info = dev_get_platdata(&pdev->dev); } if (!p->info) { dev_err(&pdev->dev, "failed to obtain device info\n"); ret = -ENXIO; goto err1; } init_completion(&p->done); p->clk = devm_clk_get(&pdev->dev, NULL); if (IS_ERR(p->clk)) { dev_err(&pdev->dev, "cannot get clock\n"); ret = PTR_ERR(p->clk); goto err1; } i = platform_get_irq(pdev, 0); if (i < 0) { dev_err(&pdev->dev, "cannot get platform IRQ\n"); ret = -ENOENT; goto err1; } r = platform_get_resource(pdev, IORESOURCE_MEM, 0); p->mapbase = devm_ioremap_resource(&pdev->dev, r); if (IS_ERR(p->mapbase)) { ret = PTR_ERR(p->mapbase); goto err1; } ret = devm_request_irq(&pdev->dev, i, sh_msiof_spi_irq, 0, dev_name(&pdev->dev), p); if (ret) { dev_err(&pdev->dev, "unable to request irq\n"); goto err1; } p->pdev = pdev; pm_runtime_enable(&pdev->dev); /* Platform data may override FIFO sizes */ p->tx_fifo_size = p->chipdata->tx_fifo_size; p->rx_fifo_size = p->chipdata->rx_fifo_size; if (p->info->tx_fifo_override) p->tx_fifo_size = p->info->tx_fifo_override; if (p->info->rx_fifo_override) p->rx_fifo_size = p->info->rx_fifo_override; /* init master code */ master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH; master->mode_bits |= SPI_LSB_FIRST | SPI_3WIRE; master->flags = p->chipdata->master_flags; master->bus_num = pdev->id; master->dev.of_node = pdev->dev.of_node; master->num_chipselect = p->info->num_chipselect; master->setup = sh_msiof_spi_setup; master->prepare_message = sh_msiof_prepare_message; master->bits_per_word_mask = SPI_BPW_RANGE_MASK(8, 32); master->auto_runtime_pm = true; master->transfer_one = sh_msiof_transfer_one; ret = sh_msiof_request_dma(p); if (ret < 0) dev_warn(&pdev->dev, "DMA not available, using PIO\n"); ret = devm_spi_register_master(&pdev->dev, master); if (ret < 0) { dev_err(&pdev->dev, "spi_register_master error.\n"); goto err2; } return 0; err2: sh_msiof_release_dma(p); pm_runtime_disable(&pdev->dev); err1: spi_master_put(master); return ret; } static int sh_msiof_spi_remove(struct platform_device *pdev) { struct sh_msiof_spi_priv *p = platform_get_drvdata(pdev); sh_msiof_release_dma(p); pm_runtime_disable(&pdev->dev); return 0; } static struct platform_device_id spi_driver_ids[] = { { "spi_sh_msiof", (kernel_ulong_t)&sh_data }, { "spi_r8a7790_msiof", (kernel_ulong_t)&r8a779x_data }, { "spi_r8a7791_msiof", (kernel_ulong_t)&r8a779x_data }, { "spi_r8a7792_msiof", (kernel_ulong_t)&r8a779x_data }, { "spi_r8a7793_msiof", (kernel_ulong_t)&r8a779x_data }, { "spi_r8a7794_msiof", (kernel_ulong_t)&r8a779x_data }, {}, }; MODULE_DEVICE_TABLE(platform, spi_driver_ids); static struct platform_driver sh_msiof_spi_drv = { .probe = sh_msiof_spi_probe, .remove = sh_msiof_spi_remove, .id_table = spi_driver_ids, .driver = { .name = "spi_sh_msiof", .of_match_table = of_match_ptr(sh_msiof_match), }, }; module_platform_driver(sh_msiof_spi_drv); MODULE_DESCRIPTION("SuperH MSIOF SPI Master Interface Driver"); MODULE_AUTHOR("Magnus Damm"); MODULE_LICENSE("GPL v2"); MODULE_ALIAS("platform:spi_sh_msiof");