// SPDX-License-Identifier: GPL-2.0 /* * SH RSPI driver * * Copyright (C) 2012, 2013 Renesas Solutions Corp. * Copyright (C) 2014 Glider bvba * * Based on spi-sh.c: * Copyright (C) 2011 Renesas Solutions Corp. */ #include <linux/module.h> #include <linux/kernel.h> #include <linux/sched.h> #include <linux/errno.h> #include <linux/interrupt.h> #include <linux/platform_device.h> #include <linux/io.h> #include <linux/clk.h> #include <linux/dmaengine.h> #include <linux/dma-mapping.h> #include <linux/of_device.h> #include <linux/pm_runtime.h> #include <linux/reset.h> #include <linux/sh_dma.h> #include <linux/spi/spi.h> #include <linux/spi/rspi.h> #include <linux/spinlock.h> #define RSPI_SPCR 0x00 /* Control Register */ #define RSPI_SSLP 0x01 /* Slave Select Polarity Register */ #define RSPI_SPPCR 0x02 /* Pin Control Register */ #define RSPI_SPSR 0x03 /* Status Register */ #define RSPI_SPDR 0x04 /* Data Register */ #define RSPI_SPSCR 0x08 /* Sequence Control Register */ #define RSPI_SPSSR 0x09 /* Sequence Status Register */ #define RSPI_SPBR 0x0a /* Bit Rate Register */ #define RSPI_SPDCR 0x0b /* Data Control Register */ #define RSPI_SPCKD 0x0c /* Clock Delay Register */ #define RSPI_SSLND 0x0d /* Slave Select Negation Delay Register */ #define RSPI_SPND 0x0e /* Next-Access Delay Register */ #define RSPI_SPCR2 0x0f /* Control Register 2 (SH only) */ #define RSPI_SPCMD0 0x10 /* Command Register 0 */ #define RSPI_SPCMD1 0x12 /* Command Register 1 */ #define RSPI_SPCMD2 0x14 /* Command Register 2 */ #define RSPI_SPCMD3 0x16 /* Command Register 3 */ #define RSPI_SPCMD4 0x18 /* Command Register 4 */ #define RSPI_SPCMD5 0x1a /* Command Register 5 */ #define RSPI_SPCMD6 0x1c /* Command Register 6 */ #define RSPI_SPCMD7 0x1e /* Command Register 7 */ #define RSPI_SPCMD(i) (RSPI_SPCMD0 + (i) * 2) #define RSPI_NUM_SPCMD 8 #define RSPI_RZ_NUM_SPCMD 4 #define QSPI_NUM_SPCMD 4 /* RSPI on RZ only */ #define RSPI_SPBFCR 0x20 /* Buffer Control Register */ #define RSPI_SPBFDR 0x22 /* Buffer Data Count Setting Register */ /* QSPI only */ #define QSPI_SPBFCR 0x18 /* Buffer Control Register */ #define QSPI_SPBDCR 0x1a /* Buffer Data Count Register */ #define QSPI_SPBMUL0 0x1c /* Transfer Data Length Multiplier Setting Register 0 */ #define QSPI_SPBMUL1 0x20 /* Transfer Data Length Multiplier Setting Register 1 */ #define QSPI_SPBMUL2 0x24 /* Transfer Data Length Multiplier Setting Register 2 */ #define QSPI_SPBMUL3 0x28 /* Transfer Data Length Multiplier Setting Register 3 */ #define QSPI_SPBMUL(i) (QSPI_SPBMUL0 + (i) * 4) /* SPCR - Control Register */ #define SPCR_SPRIE 0x80 /* Receive Interrupt Enable */ #define SPCR_SPE 0x40 /* Function Enable */ #define SPCR_SPTIE 0x20 /* Transmit Interrupt Enable */ #define SPCR_SPEIE 0x10 /* Error Interrupt Enable */ #define SPCR_MSTR 0x08 /* Master/Slave Mode Select */ #define SPCR_MODFEN 0x04 /* Mode Fault Error Detection Enable */ /* RSPI on SH only */ #define SPCR_TXMD 0x02 /* TX Only Mode (vs. Full Duplex) */ #define SPCR_SPMS 0x01 /* 3-wire Mode (vs. 4-wire) */ /* QSPI on R-Car Gen2 only */ #define SPCR_WSWAP 0x02 /* Word Swap of read-data for DMAC */ #define SPCR_BSWAP 0x01 /* Byte Swap of read-data for DMAC */ /* SSLP - Slave Select Polarity Register */ #define SSLP_SSLP(i) BIT(i) /* SSLi Signal Polarity Setting */ /* SPPCR - Pin Control Register */ #define SPPCR_MOIFE 0x20 /* MOSI Idle Value Fixing Enable */ #define SPPCR_MOIFV 0x10 /* MOSI Idle Fixed Value */ #define SPPCR_SPOM 0x04 #define SPPCR_SPLP2 0x02 /* Loopback Mode 2 (non-inverting) */ #define SPPCR_SPLP 0x01 /* Loopback Mode (inverting) */ #define SPPCR_IO3FV 0x04 /* Single-/Dual-SPI Mode IO3 Output Fixed Value */ #define SPPCR_IO2FV 0x04 /* Single-/Dual-SPI Mode IO2 Output Fixed Value */ /* SPSR - Status Register */ #define SPSR_SPRF 0x80 /* Receive Buffer Full Flag */ #define SPSR_TEND 0x40 /* Transmit End */ #define SPSR_SPTEF 0x20 /* Transmit Buffer Empty Flag */ #define SPSR_PERF 0x08 /* Parity Error Flag */ #define SPSR_MODF 0x04 /* Mode Fault Error Flag */ #define SPSR_IDLNF 0x02 /* RSPI Idle Flag */ #define SPSR_OVRF 0x01 /* Overrun Error Flag (RSPI only) */ /* SPSCR - Sequence Control Register */ #define SPSCR_SPSLN_MASK 0x07 /* Sequence Length Specification */ /* SPSSR - Sequence Status Register */ #define SPSSR_SPECM_MASK 0x70 /* Command Error Mask */ #define SPSSR_SPCP_MASK 0x07 /* Command Pointer Mask */ /* SPDCR - Data Control Register */ #define SPDCR_TXDMY 0x80 /* Dummy Data Transmission Enable */ #define SPDCR_SPLW1 0x40 /* Access Width Specification (RZ) */ #define SPDCR_SPLW0 0x20 /* Access Width Specification (RZ) */ #define SPDCR_SPLLWORD (SPDCR_SPLW1 | SPDCR_SPLW0) #define SPDCR_SPLWORD SPDCR_SPLW1 #define SPDCR_SPLBYTE SPDCR_SPLW0 #define SPDCR_SPLW 0x20 /* Access Width Specification (SH) */ #define SPDCR_SPRDTD 0x10 /* Receive Transmit Data Select (SH) */ #define SPDCR_SLSEL1 0x08 #define SPDCR_SLSEL0 0x04 #define SPDCR_SLSEL_MASK 0x0c /* SSL1 Output Select (SH) */ #define SPDCR_SPFC1 0x02 #define SPDCR_SPFC0 0x01 #define SPDCR_SPFC_MASK 0x03 /* Frame Count Setting (1-4) (SH) */ /* SPCKD - Clock Delay Register */ #define SPCKD_SCKDL_MASK 0x07 /* Clock Delay Setting (1-8) */ /* SSLND - Slave Select Negation Delay Register */ #define SSLND_SLNDL_MASK 0x07 /* SSL Negation Delay Setting (1-8) */ /* SPND - Next-Access Delay Register */ #define SPND_SPNDL_MASK 0x07 /* Next-Access Delay Setting (1-8) */ /* SPCR2 - Control Register 2 */ #define SPCR2_PTE 0x08 /* Parity Self-Test Enable */ #define SPCR2_SPIE 0x04 /* Idle Interrupt Enable */ #define SPCR2_SPOE 0x02 /* Odd Parity Enable (vs. Even) */ #define SPCR2_SPPE 0x01 /* Parity Enable */ /* SPCMDn - Command Registers */ #define SPCMD_SCKDEN 0x8000 /* Clock Delay Setting Enable */ #define SPCMD_SLNDEN 0x4000 /* SSL Negation Delay Setting Enable */ #define SPCMD_SPNDEN 0x2000 /* Next-Access Delay Enable */ #define SPCMD_LSBF 0x1000 /* LSB First */ #define SPCMD_SPB_MASK 0x0f00 /* Data Length Setting */ #define SPCMD_SPB_8_TO_16(bit) (((bit - 1) << 8) & SPCMD_SPB_MASK) #define SPCMD_SPB_8BIT 0x0000 /* QSPI only */ #define SPCMD_SPB_16BIT 0x0100 #define SPCMD_SPB_20BIT 0x0000 #define SPCMD_SPB_24BIT 0x0100 #define SPCMD_SPB_32BIT 0x0200 #define SPCMD_SSLKP 0x0080 /* SSL Signal Level Keeping */ #define SPCMD_SPIMOD_MASK 0x0060 /* SPI Operating Mode (QSPI only) */ #define SPCMD_SPIMOD1 0x0040 #define SPCMD_SPIMOD0 0x0020 #define SPCMD_SPIMOD_SINGLE 0 #define SPCMD_SPIMOD_DUAL SPCMD_SPIMOD0 #define SPCMD_SPIMOD_QUAD SPCMD_SPIMOD1 #define SPCMD_SPRW 0x0010 /* SPI Read/Write Access (Dual/Quad) */ #define SPCMD_SSLA(i) ((i) << 4) /* SSL Assert Signal Setting */ #define SPCMD_BRDV_MASK 0x000c /* Bit Rate Division Setting */ #define SPCMD_BRDV(brdv) ((brdv) << 2) #define SPCMD_CPOL 0x0002 /* Clock Polarity Setting */ #define SPCMD_CPHA 0x0001 /* Clock Phase Setting */ /* SPBFCR - Buffer Control Register */ #define SPBFCR_TXRST 0x80 /* Transmit Buffer Data Reset */ #define SPBFCR_RXRST 0x40 /* Receive Buffer Data Reset */ #define SPBFCR_TXTRG_MASK 0x30 /* Transmit Buffer Data Triggering Number */ #define SPBFCR_RXTRG_MASK 0x07 /* Receive Buffer Data Triggering Number */ /* QSPI on R-Car Gen2 */ #define SPBFCR_TXTRG_1B 0x00 /* 31 bytes (1 byte available) */ #define SPBFCR_TXTRG_32B 0x30 /* 0 byte (32 bytes available) */ #define SPBFCR_RXTRG_1B 0x00 /* 1 byte (31 bytes available) */ #define SPBFCR_RXTRG_32B 0x07 /* 32 bytes (0 byte available) */ #define QSPI_BUFFER_SIZE 32u struct rspi_data { void __iomem *addr; u32 speed_hz; struct spi_controller *ctlr; struct platform_device *pdev; wait_queue_head_t wait; spinlock_t lock; /* Protects RMW-access to RSPI_SSLP */ struct clk *clk; u16 spcmd; u8 spsr; u8 sppcr; int rx_irq, tx_irq; const struct spi_ops *ops; unsigned dma_callbacked:1; unsigned byte_access:1; }; static void rspi_write8(const struct rspi_data *rspi, u8 data, u16 offset) { iowrite8(data, rspi->addr + offset); } static void rspi_write16(const struct rspi_data *rspi, u16 data, u16 offset) { iowrite16(data, rspi->addr + offset); } static void rspi_write32(const struct rspi_data *rspi, u32 data, u16 offset) { iowrite32(data, rspi->addr + offset); } static u8 rspi_read8(const struct rspi_data *rspi, u16 offset) { return ioread8(rspi->addr + offset); } static u16 rspi_read16(const struct rspi_data *rspi, u16 offset) { return ioread16(rspi->addr + offset); } static void rspi_write_data(const struct rspi_data *rspi, u16 data) { if (rspi->byte_access) rspi_write8(rspi, data, RSPI_SPDR); else /* 16 bit */ rspi_write16(rspi, data, RSPI_SPDR); } static u16 rspi_read_data(const struct rspi_data *rspi) { if (rspi->byte_access) return rspi_read8(rspi, RSPI_SPDR); else /* 16 bit */ return rspi_read16(rspi, RSPI_SPDR); } /* optional functions */ struct spi_ops { int (*set_config_register)(struct rspi_data *rspi, int access_size); int (*transfer_one)(struct spi_controller *ctlr, struct spi_device *spi, struct spi_transfer *xfer); u16 extra_mode_bits; u16 min_div; u16 max_div; u16 flags; u16 fifo_size; u8 num_hw_ss; }; static void rspi_set_rate(struct rspi_data *rspi) { unsigned long clksrc; int brdv = 0, spbr; clksrc = clk_get_rate(rspi->clk); spbr = DIV_ROUND_UP(clksrc, 2 * rspi->speed_hz) - 1; while (spbr > 255 && brdv < 3) { brdv++; spbr = DIV_ROUND_UP(spbr + 1, 2) - 1; } rspi_write8(rspi, clamp(spbr, 0, 255), RSPI_SPBR); rspi->spcmd |= SPCMD_BRDV(brdv); rspi->speed_hz = DIV_ROUND_UP(clksrc, (2U << brdv) * (spbr + 1)); } /* * functions for RSPI on legacy SH */ static int rspi_set_config_register(struct rspi_data *rspi, int access_size) { /* Sets output mode, MOSI signal, and (optionally) loopback */ rspi_write8(rspi, rspi->sppcr, RSPI_SPPCR); /* Sets transfer bit rate */ rspi_set_rate(rspi); /* Disable dummy transmission, set 16-bit word access, 1 frame */ rspi_write8(rspi, 0, RSPI_SPDCR); rspi->byte_access = 0; /* Sets RSPCK, SSL, next-access delay value */ rspi_write8(rspi, 0x00, RSPI_SPCKD); rspi_write8(rspi, 0x00, RSPI_SSLND); rspi_write8(rspi, 0x00, RSPI_SPND); /* Sets parity, interrupt mask */ rspi_write8(rspi, 0x00, RSPI_SPCR2); /* Resets sequencer */ rspi_write8(rspi, 0, RSPI_SPSCR); rspi->spcmd |= SPCMD_SPB_8_TO_16(access_size); rspi_write16(rspi, rspi->spcmd, RSPI_SPCMD0); /* Sets RSPI mode */ rspi_write8(rspi, SPCR_MSTR, RSPI_SPCR); return 0; } /* * functions for RSPI on RZ */ static int rspi_rz_set_config_register(struct rspi_data *rspi, int access_size) { /* Sets output mode, MOSI signal, and (optionally) loopback */ rspi_write8(rspi, rspi->sppcr, RSPI_SPPCR); /* Sets transfer bit rate */ rspi_set_rate(rspi); /* Disable dummy transmission, set byte access */ rspi_write8(rspi, SPDCR_SPLBYTE, RSPI_SPDCR); rspi->byte_access = 1; /* Sets RSPCK, SSL, next-access delay value */ rspi_write8(rspi, 0x00, RSPI_SPCKD); rspi_write8(rspi, 0x00, RSPI_SSLND); rspi_write8(rspi, 0x00, RSPI_SPND); /* Resets sequencer */ rspi_write8(rspi, 0, RSPI_SPSCR); rspi->spcmd |= SPCMD_SPB_8_TO_16(access_size); rspi_write16(rspi, rspi->spcmd, RSPI_SPCMD0); /* Sets RSPI mode */ rspi_write8(rspi, SPCR_MSTR, RSPI_SPCR); return 0; } /* * functions for QSPI */ static int qspi_set_config_register(struct rspi_data *rspi, int access_size) { unsigned long clksrc; int brdv = 0, spbr; /* Sets output mode, MOSI signal, and (optionally) loopback */ rspi_write8(rspi, rspi->sppcr, RSPI_SPPCR); /* Sets transfer bit rate */ clksrc = clk_get_rate(rspi->clk); if (rspi->speed_hz >= clksrc) { spbr = 0; rspi->speed_hz = clksrc; } else { spbr = DIV_ROUND_UP(clksrc, 2 * rspi->speed_hz); while (spbr > 255 && brdv < 3) { brdv++; spbr = DIV_ROUND_UP(spbr, 2); } spbr = clamp(spbr, 0, 255); rspi->speed_hz = DIV_ROUND_UP(clksrc, (2U << brdv) * spbr); } rspi_write8(rspi, spbr, RSPI_SPBR); rspi->spcmd |= SPCMD_BRDV(brdv); /* Disable dummy transmission, set byte access */ rspi_write8(rspi, 0, RSPI_SPDCR); rspi->byte_access = 1; /* Sets RSPCK, SSL, next-access delay value */ rspi_write8(rspi, 0x00, RSPI_SPCKD); rspi_write8(rspi, 0x00, RSPI_SSLND); rspi_write8(rspi, 0x00, RSPI_SPND); /* Data Length Setting */ if (access_size == 8) rspi->spcmd |= SPCMD_SPB_8BIT; else if (access_size == 16) rspi->spcmd |= SPCMD_SPB_16BIT; else rspi->spcmd |= SPCMD_SPB_32BIT; rspi->spcmd |= SPCMD_SCKDEN | SPCMD_SLNDEN | SPCMD_SPNDEN; /* Resets transfer data length */ rspi_write32(rspi, 0, QSPI_SPBMUL0); /* Resets transmit and receive buffer */ rspi_write8(rspi, SPBFCR_TXRST | SPBFCR_RXRST, QSPI_SPBFCR); /* Sets buffer to allow normal operation */ rspi_write8(rspi, 0x00, QSPI_SPBFCR); /* Resets sequencer */ rspi_write8(rspi, 0, RSPI_SPSCR); rspi_write16(rspi, rspi->spcmd, RSPI_SPCMD0); /* Sets RSPI mode */ rspi_write8(rspi, SPCR_MSTR, RSPI_SPCR); return 0; } static void qspi_update(const struct rspi_data *rspi, u8 mask, u8 val, u8 reg) { u8 data; data = rspi_read8(rspi, reg); data &= ~mask; data |= (val & mask); rspi_write8(rspi, data, reg); } static unsigned int qspi_set_send_trigger(struct rspi_data *rspi, unsigned int len) { unsigned int n; n = min(len, QSPI_BUFFER_SIZE); if (len >= QSPI_BUFFER_SIZE) { /* sets triggering number to 32 bytes */ qspi_update(rspi, SPBFCR_TXTRG_MASK, SPBFCR_TXTRG_32B, QSPI_SPBFCR); } else { /* sets triggering number to 1 byte */ qspi_update(rspi, SPBFCR_TXTRG_MASK, SPBFCR_TXTRG_1B, QSPI_SPBFCR); } return n; } static int qspi_set_receive_trigger(struct rspi_data *rspi, unsigned int len) { unsigned int n; n = min(len, QSPI_BUFFER_SIZE); if (len >= QSPI_BUFFER_SIZE) { /* sets triggering number to 32 bytes */ qspi_update(rspi, SPBFCR_RXTRG_MASK, SPBFCR_RXTRG_32B, QSPI_SPBFCR); } else { /* sets triggering number to 1 byte */ qspi_update(rspi, SPBFCR_RXTRG_MASK, SPBFCR_RXTRG_1B, QSPI_SPBFCR); } return n; } static void rspi_enable_irq(const struct rspi_data *rspi, u8 enable) { rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) | enable, RSPI_SPCR); } static void rspi_disable_irq(const struct rspi_data *rspi, u8 disable) { rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) & ~disable, RSPI_SPCR); } static int rspi_wait_for_interrupt(struct rspi_data *rspi, u8 wait_mask, u8 enable_bit) { int ret; rspi->spsr = rspi_read8(rspi, RSPI_SPSR); if (rspi->spsr & wait_mask) return 0; rspi_enable_irq(rspi, enable_bit); ret = wait_event_timeout(rspi->wait, rspi->spsr & wait_mask, HZ); if (ret == 0 && !(rspi->spsr & wait_mask)) return -ETIMEDOUT; return 0; } static inline int rspi_wait_for_tx_empty(struct rspi_data *rspi) { return rspi_wait_for_interrupt(rspi, SPSR_SPTEF, SPCR_SPTIE); } static inline int rspi_wait_for_rx_full(struct rspi_data *rspi) { return rspi_wait_for_interrupt(rspi, SPSR_SPRF, SPCR_SPRIE); } static int rspi_data_out(struct rspi_data *rspi, u8 data) { int error = rspi_wait_for_tx_empty(rspi); if (error < 0) { dev_err(&rspi->ctlr->dev, "transmit timeout\n"); return error; } rspi_write_data(rspi, data); return 0; } static int rspi_data_in(struct rspi_data *rspi) { int error; u8 data; error = rspi_wait_for_rx_full(rspi); if (error < 0) { dev_err(&rspi->ctlr->dev, "receive timeout\n"); return error; } data = rspi_read_data(rspi); return data; } static int rspi_pio_transfer(struct rspi_data *rspi, const u8 *tx, u8 *rx, unsigned int n) { while (n-- > 0) { if (tx) { int ret = rspi_data_out(rspi, *tx++); if (ret < 0) return ret; } if (rx) { int ret = rspi_data_in(rspi); if (ret < 0) return ret; *rx++ = ret; } } return 0; } static void rspi_dma_complete(void *arg) { struct rspi_data *rspi = arg; rspi->dma_callbacked = 1; wake_up_interruptible(&rspi->wait); } static int rspi_dma_transfer(struct rspi_data *rspi, struct sg_table *tx, struct sg_table *rx) { struct dma_async_tx_descriptor *desc_tx = NULL, *desc_rx = NULL; u8 irq_mask = 0; unsigned int other_irq = 0; dma_cookie_t cookie; int ret; /* First prepare and submit the DMA request(s), as this may fail */ if (rx) { desc_rx = dmaengine_prep_slave_sg(rspi->ctlr->dma_rx, rx->sgl, rx->nents, DMA_DEV_TO_MEM, DMA_PREP_INTERRUPT | DMA_CTRL_ACK); if (!desc_rx) { ret = -EAGAIN; goto no_dma_rx; } desc_rx->callback = rspi_dma_complete; desc_rx->callback_param = rspi; cookie = dmaengine_submit(desc_rx); if (dma_submit_error(cookie)) { ret = cookie; goto no_dma_rx; } irq_mask |= SPCR_SPRIE; } if (tx) { desc_tx = dmaengine_prep_slave_sg(rspi->ctlr->dma_tx, tx->sgl, tx->nents, DMA_MEM_TO_DEV, 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 = rspi_dma_complete; desc_tx->callback_param = rspi; } cookie = dmaengine_submit(desc_tx); if (dma_submit_error(cookie)) { ret = cookie; goto no_dma_tx; } irq_mask |= SPCR_SPTIE; } /* * DMAC needs SPxIE, but if SPxIE is set, the IRQ routine will be * called. So, this driver disables the IRQ while DMA transfer. */ if (tx) disable_irq(other_irq = rspi->tx_irq); if (rx && rspi->rx_irq != other_irq) disable_irq(rspi->rx_irq); rspi_enable_irq(rspi, irq_mask); rspi->dma_callbacked = 0; /* Now start DMA */ if (rx) dma_async_issue_pending(rspi->ctlr->dma_rx); if (tx) dma_async_issue_pending(rspi->ctlr->dma_tx); ret = wait_event_interruptible_timeout(rspi->wait, rspi->dma_callbacked, HZ); if (ret > 0 && rspi->dma_callbacked) { ret = 0; } else { if (!ret) { dev_err(&rspi->ctlr->dev, "DMA timeout\n"); ret = -ETIMEDOUT; } if (tx) dmaengine_terminate_sync(rspi->ctlr->dma_tx); if (rx) dmaengine_terminate_sync(rspi->ctlr->dma_rx); } rspi_disable_irq(rspi, irq_mask); if (tx) enable_irq(rspi->tx_irq); if (rx && rspi->rx_irq != other_irq) enable_irq(rspi->rx_irq); return ret; no_dma_tx: if (rx) dmaengine_terminate_sync(rspi->ctlr->dma_rx); no_dma_rx: if (ret == -EAGAIN) { dev_warn_once(&rspi->ctlr->dev, "DMA not available, falling back to PIO\n"); } return ret; } static void rspi_receive_init(const struct rspi_data *rspi) { u8 spsr; spsr = rspi_read8(rspi, RSPI_SPSR); if (spsr & SPSR_SPRF) rspi_read_data(rspi); /* dummy read */ if (spsr & SPSR_OVRF) rspi_write8(rspi, rspi_read8(rspi, RSPI_SPSR) & ~SPSR_OVRF, RSPI_SPSR); } static void rspi_rz_receive_init(const struct rspi_data *rspi) { rspi_receive_init(rspi); rspi_write8(rspi, SPBFCR_TXRST | SPBFCR_RXRST, RSPI_SPBFCR); rspi_write8(rspi, 0, RSPI_SPBFCR); } static void qspi_receive_init(const struct rspi_data *rspi) { u8 spsr; spsr = rspi_read8(rspi, RSPI_SPSR); if (spsr & SPSR_SPRF) rspi_read_data(rspi); /* dummy read */ rspi_write8(rspi, SPBFCR_TXRST | SPBFCR_RXRST, QSPI_SPBFCR); rspi_write8(rspi, 0, QSPI_SPBFCR); } static bool __rspi_can_dma(const struct rspi_data *rspi, const struct spi_transfer *xfer) { return xfer->len > rspi->ops->fifo_size; } static bool rspi_can_dma(struct spi_controller *ctlr, struct spi_device *spi, struct spi_transfer *xfer) { struct rspi_data *rspi = spi_controller_get_devdata(ctlr); return __rspi_can_dma(rspi, xfer); } static int rspi_dma_check_then_transfer(struct rspi_data *rspi, struct spi_transfer *xfer) { if (!rspi->ctlr->can_dma || !__rspi_can_dma(rspi, xfer)) return -EAGAIN; /* rx_buf can be NULL on RSPI on SH in TX-only Mode */ return rspi_dma_transfer(rspi, &xfer->tx_sg, xfer->rx_buf ? &xfer->rx_sg : NULL); } static int rspi_common_transfer(struct rspi_data *rspi, struct spi_transfer *xfer) { int ret; xfer->effective_speed_hz = rspi->speed_hz; ret = rspi_dma_check_then_transfer(rspi, xfer); if (ret != -EAGAIN) return ret; ret = rspi_pio_transfer(rspi, xfer->tx_buf, xfer->rx_buf, xfer->len); if (ret < 0) return ret; /* Wait for the last transmission */ rspi_wait_for_tx_empty(rspi); return 0; } static int rspi_transfer_one(struct spi_controller *ctlr, struct spi_device *spi, struct spi_transfer *xfer) { struct rspi_data *rspi = spi_controller_get_devdata(ctlr); u8 spcr; spcr = rspi_read8(rspi, RSPI_SPCR); if (xfer->rx_buf) { rspi_receive_init(rspi); spcr &= ~SPCR_TXMD; } else { spcr |= SPCR_TXMD; } rspi_write8(rspi, spcr, RSPI_SPCR); return rspi_common_transfer(rspi, xfer); } static int rspi_rz_transfer_one(struct spi_controller *ctlr, struct spi_device *spi, struct spi_transfer *xfer) { struct rspi_data *rspi = spi_controller_get_devdata(ctlr); rspi_rz_receive_init(rspi); return rspi_common_transfer(rspi, xfer); } static int qspi_trigger_transfer_out_in(struct rspi_data *rspi, const u8 *tx, u8 *rx, unsigned int len) { unsigned int i, n; int ret; while (len > 0) { n = qspi_set_send_trigger(rspi, len); qspi_set_receive_trigger(rspi, len); ret = rspi_wait_for_tx_empty(rspi); if (ret < 0) { dev_err(&rspi->ctlr->dev, "transmit timeout\n"); return ret; } for (i = 0; i < n; i++) rspi_write_data(rspi, *tx++); ret = rspi_wait_for_rx_full(rspi); if (ret < 0) { dev_err(&rspi->ctlr->dev, "receive timeout\n"); return ret; } for (i = 0; i < n; i++) *rx++ = rspi_read_data(rspi); len -= n; } return 0; } static int qspi_transfer_out_in(struct rspi_data *rspi, struct spi_transfer *xfer) { int ret; qspi_receive_init(rspi); ret = rspi_dma_check_then_transfer(rspi, xfer); if (ret != -EAGAIN) return ret; return qspi_trigger_transfer_out_in(rspi, xfer->tx_buf, xfer->rx_buf, xfer->len); } static int qspi_transfer_out(struct rspi_data *rspi, struct spi_transfer *xfer) { const u8 *tx = xfer->tx_buf; unsigned int n = xfer->len; unsigned int i, len; int ret; if (rspi->ctlr->can_dma && __rspi_can_dma(rspi, xfer)) { ret = rspi_dma_transfer(rspi, &xfer->tx_sg, NULL); if (ret != -EAGAIN) return ret; } while (n > 0) { len = qspi_set_send_trigger(rspi, n); ret = rspi_wait_for_tx_empty(rspi); if (ret < 0) { dev_err(&rspi->ctlr->dev, "transmit timeout\n"); return ret; } for (i = 0; i < len; i++) rspi_write_data(rspi, *tx++); n -= len; } /* Wait for the last transmission */ rspi_wait_for_tx_empty(rspi); return 0; } static int qspi_transfer_in(struct rspi_data *rspi, struct spi_transfer *xfer) { u8 *rx = xfer->rx_buf; unsigned int n = xfer->len; unsigned int i, len; int ret; if (rspi->ctlr->can_dma && __rspi_can_dma(rspi, xfer)) { ret = rspi_dma_transfer(rspi, NULL, &xfer->rx_sg); if (ret != -EAGAIN) return ret; } while (n > 0) { len = qspi_set_receive_trigger(rspi, n); ret = rspi_wait_for_rx_full(rspi); if (ret < 0) { dev_err(&rspi->ctlr->dev, "receive timeout\n"); return ret; } for (i = 0; i < len; i++) *rx++ = rspi_read_data(rspi); n -= len; } return 0; } static int qspi_transfer_one(struct spi_controller *ctlr, struct spi_device *spi, struct spi_transfer *xfer) { struct rspi_data *rspi = spi_controller_get_devdata(ctlr); xfer->effective_speed_hz = rspi->speed_hz; if (spi->mode & SPI_LOOP) { return qspi_transfer_out_in(rspi, xfer); } else if (xfer->tx_nbits > SPI_NBITS_SINGLE) { /* Quad or Dual SPI Write */ return qspi_transfer_out(rspi, xfer); } else if (xfer->rx_nbits > SPI_NBITS_SINGLE) { /* Quad or Dual SPI Read */ return qspi_transfer_in(rspi, xfer); } else { /* Single SPI Transfer */ return qspi_transfer_out_in(rspi, xfer); } } static u16 qspi_transfer_mode(const struct spi_transfer *xfer) { if (xfer->tx_buf) switch (xfer->tx_nbits) { case SPI_NBITS_QUAD: return SPCMD_SPIMOD_QUAD; case SPI_NBITS_DUAL: return SPCMD_SPIMOD_DUAL; default: return 0; } if (xfer->rx_buf) switch (xfer->rx_nbits) { case SPI_NBITS_QUAD: return SPCMD_SPIMOD_QUAD | SPCMD_SPRW; case SPI_NBITS_DUAL: return SPCMD_SPIMOD_DUAL | SPCMD_SPRW; default: return 0; } return 0; } static int qspi_setup_sequencer(struct rspi_data *rspi, const struct spi_message *msg) { const struct spi_transfer *xfer; unsigned int i = 0, len = 0; u16 current_mode = 0xffff, mode; list_for_each_entry(xfer, &msg->transfers, transfer_list) { mode = qspi_transfer_mode(xfer); if (mode == current_mode) { len += xfer->len; continue; } /* Transfer mode change */ if (i) { /* Set transfer data length of previous transfer */ rspi_write32(rspi, len, QSPI_SPBMUL(i - 1)); } if (i >= QSPI_NUM_SPCMD) { dev_err(&msg->spi->dev, "Too many different transfer modes"); return -EINVAL; } /* Program transfer mode for this transfer */ rspi_write16(rspi, rspi->spcmd | mode, RSPI_SPCMD(i)); current_mode = mode; len = xfer->len; i++; } if (i) { /* Set final transfer data length and sequence length */ rspi_write32(rspi, len, QSPI_SPBMUL(i - 1)); rspi_write8(rspi, i - 1, RSPI_SPSCR); } return 0; } static int rspi_setup(struct spi_device *spi) { struct rspi_data *rspi = spi_controller_get_devdata(spi->controller); u8 sslp; if (spi->cs_gpiod) return 0; pm_runtime_get_sync(&rspi->pdev->dev); spin_lock_irq(&rspi->lock); sslp = rspi_read8(rspi, RSPI_SSLP); if (spi->mode & SPI_CS_HIGH) sslp |= SSLP_SSLP(spi->chip_select); else sslp &= ~SSLP_SSLP(spi->chip_select); rspi_write8(rspi, sslp, RSPI_SSLP); spin_unlock_irq(&rspi->lock); pm_runtime_put(&rspi->pdev->dev); return 0; } static int rspi_prepare_message(struct spi_controller *ctlr, struct spi_message *msg) { struct rspi_data *rspi = spi_controller_get_devdata(ctlr); struct spi_device *spi = msg->spi; const struct spi_transfer *xfer; int ret; /* * As the Bit Rate Register must not be changed while the device is * active, all transfers in a message must use the same bit rate. * In theory, the sequencer could be enabled, and each Command Register * could divide the base bit rate by a different value. * However, most RSPI variants do not have Transfer Data Length * Multiplier Setting Registers, so each sequence step would be limited * to a single word, making this feature unsuitable for large * transfers, which would gain most from it. */ rspi->speed_hz = spi->max_speed_hz; list_for_each_entry(xfer, &msg->transfers, transfer_list) { if (xfer->speed_hz < rspi->speed_hz) rspi->speed_hz = xfer->speed_hz; } rspi->spcmd = SPCMD_SSLKP; if (spi->mode & SPI_CPOL) rspi->spcmd |= SPCMD_CPOL; if (spi->mode & SPI_CPHA) rspi->spcmd |= SPCMD_CPHA; if (spi->mode & SPI_LSB_FIRST) rspi->spcmd |= SPCMD_LSBF; /* Configure slave signal to assert */ rspi->spcmd |= SPCMD_SSLA(spi->cs_gpiod ? rspi->ctlr->unused_native_cs : spi->chip_select); /* CMOS output mode and MOSI signal from previous transfer */ rspi->sppcr = 0; if (spi->mode & SPI_LOOP) rspi->sppcr |= SPPCR_SPLP; rspi->ops->set_config_register(rspi, 8); if (msg->spi->mode & (SPI_TX_DUAL | SPI_TX_QUAD | SPI_RX_DUAL | SPI_RX_QUAD)) { /* Setup sequencer for messages with multiple transfer modes */ ret = qspi_setup_sequencer(rspi, msg); if (ret < 0) return ret; } /* Enable SPI function in master mode */ rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) | SPCR_SPE, RSPI_SPCR); return 0; } static int rspi_unprepare_message(struct spi_controller *ctlr, struct spi_message *msg) { struct rspi_data *rspi = spi_controller_get_devdata(ctlr); /* Disable SPI function */ rspi_write8(rspi, rspi_read8(rspi, RSPI_SPCR) & ~SPCR_SPE, RSPI_SPCR); /* Reset sequencer for Single SPI Transfers */ rspi_write16(rspi, rspi->spcmd, RSPI_SPCMD0); rspi_write8(rspi, 0, RSPI_SPSCR); return 0; } static irqreturn_t rspi_irq_mux(int irq, void *_sr) { struct rspi_data *rspi = _sr; u8 spsr; irqreturn_t ret = IRQ_NONE; u8 disable_irq = 0; rspi->spsr = spsr = rspi_read8(rspi, RSPI_SPSR); if (spsr & SPSR_SPRF) disable_irq |= SPCR_SPRIE; if (spsr & SPSR_SPTEF) disable_irq |= SPCR_SPTIE; if (disable_irq) { ret = IRQ_HANDLED; rspi_disable_irq(rspi, disable_irq); wake_up(&rspi->wait); } return ret; } static irqreturn_t rspi_irq_rx(int irq, void *_sr) { struct rspi_data *rspi = _sr; u8 spsr; rspi->spsr = spsr = rspi_read8(rspi, RSPI_SPSR); if (spsr & SPSR_SPRF) { rspi_disable_irq(rspi, SPCR_SPRIE); wake_up(&rspi->wait); return IRQ_HANDLED; } return 0; } static irqreturn_t rspi_irq_tx(int irq, void *_sr) { struct rspi_data *rspi = _sr; u8 spsr; rspi->spsr = spsr = rspi_read8(rspi, RSPI_SPSR); if (spsr & SPSR_SPTEF) { rspi_disable_irq(rspi, SPCR_SPTIE); wake_up(&rspi->wait); return IRQ_HANDLED; } return 0; } static struct dma_chan *rspi_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_1_BYTE; } else { cfg.src_addr = port_addr; cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE; } 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 rspi_request_dma(struct device *dev, struct spi_controller *ctlr, const struct resource *res) { const struct rspi_plat_data *rspi_pd = dev_get_platdata(dev); unsigned int dma_tx_id, dma_rx_id; 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 (rspi_pd && rspi_pd->dma_tx_id && rspi_pd->dma_rx_id) { dma_tx_id = rspi_pd->dma_tx_id; dma_rx_id = rspi_pd->dma_rx_id; } else { /* The driver assumes no error. */ return 0; } ctlr->dma_tx = rspi_request_dma_chan(dev, DMA_MEM_TO_DEV, dma_tx_id, res->start + RSPI_SPDR); if (!ctlr->dma_tx) return -ENODEV; ctlr->dma_rx = rspi_request_dma_chan(dev, DMA_DEV_TO_MEM, dma_rx_id, res->start + RSPI_SPDR); if (!ctlr->dma_rx) { dma_release_channel(ctlr->dma_tx); ctlr->dma_tx = NULL; return -ENODEV; } ctlr->can_dma = rspi_can_dma; dev_info(dev, "DMA available"); return 0; } static void rspi_release_dma(struct spi_controller *ctlr) { if (ctlr->dma_tx) dma_release_channel(ctlr->dma_tx); if (ctlr->dma_rx) dma_release_channel(ctlr->dma_rx); } static int rspi_remove(struct platform_device *pdev) { struct rspi_data *rspi = platform_get_drvdata(pdev); rspi_release_dma(rspi->ctlr); pm_runtime_disable(&pdev->dev); return 0; } static const struct spi_ops rspi_ops = { .set_config_register = rspi_set_config_register, .transfer_one = rspi_transfer_one, .min_div = 2, .max_div = 4096, .flags = SPI_CONTROLLER_MUST_TX, .fifo_size = 8, .num_hw_ss = 2, }; static const struct spi_ops rspi_rz_ops = { .set_config_register = rspi_rz_set_config_register, .transfer_one = rspi_rz_transfer_one, .min_div = 2, .max_div = 4096, .flags = SPI_CONTROLLER_MUST_RX | SPI_CONTROLLER_MUST_TX, .fifo_size = 8, /* 8 for TX, 32 for RX */ .num_hw_ss = 1, }; static const struct spi_ops qspi_ops = { .set_config_register = qspi_set_config_register, .transfer_one = qspi_transfer_one, .extra_mode_bits = SPI_TX_DUAL | SPI_TX_QUAD | SPI_RX_DUAL | SPI_RX_QUAD, .min_div = 1, .max_div = 4080, .flags = SPI_CONTROLLER_MUST_RX | SPI_CONTROLLER_MUST_TX, .fifo_size = 32, .num_hw_ss = 1, }; #ifdef CONFIG_OF static const struct of_device_id rspi_of_match[] = { /* RSPI on legacy SH */ { .compatible = "renesas,rspi", .data = &rspi_ops }, /* RSPI on RZ/A1H */ { .compatible = "renesas,rspi-rz", .data = &rspi_rz_ops }, /* QSPI on R-Car Gen2 */ { .compatible = "renesas,qspi", .data = &qspi_ops }, { /* sentinel */ } }; MODULE_DEVICE_TABLE(of, rspi_of_match); static void rspi_reset_control_assert(void *data) { reset_control_assert(data); } static int rspi_parse_dt(struct device *dev, struct spi_controller *ctlr) { struct reset_control *rstc; u32 num_cs; int error; /* Parse DT properties */ error = of_property_read_u32(dev->of_node, "num-cs", &num_cs); if (error) { dev_err(dev, "of_property_read_u32 num-cs failed %d\n", error); return error; } ctlr->num_chipselect = num_cs; rstc = devm_reset_control_get_optional_exclusive(dev, NULL); if (IS_ERR(rstc)) return dev_err_probe(dev, PTR_ERR(rstc), "failed to get reset ctrl\n"); error = reset_control_deassert(rstc); if (error) { dev_err(dev, "failed to deassert reset %d\n", error); return error; } error = devm_add_action_or_reset(dev, rspi_reset_control_assert, rstc); if (error) { dev_err(dev, "failed to register assert devm action, %d\n", error); return error; } return 0; } #else #define rspi_of_match NULL static inline int rspi_parse_dt(struct device *dev, struct spi_controller *ctlr) { return -EINVAL; } #endif /* CONFIG_OF */ static int rspi_request_irq(struct device *dev, unsigned int irq, irq_handler_t handler, const char *suffix, void *dev_id) { const char *name = devm_kasprintf(dev, GFP_KERNEL, "%s:%s", dev_name(dev), suffix); if (!name) return -ENOMEM; return devm_request_irq(dev, irq, handler, 0, name, dev_id); } static int rspi_probe(struct platform_device *pdev) { struct resource *res; struct spi_controller *ctlr; struct rspi_data *rspi; int ret; const struct rspi_plat_data *rspi_pd; const struct spi_ops *ops; unsigned long clksrc; ctlr = spi_alloc_master(&pdev->dev, sizeof(struct rspi_data)); if (ctlr == NULL) return -ENOMEM; ops = of_device_get_match_data(&pdev->dev); if (ops) { ret = rspi_parse_dt(&pdev->dev, ctlr); if (ret) goto error1; } else { ops = (struct spi_ops *)pdev->id_entry->driver_data; rspi_pd = dev_get_platdata(&pdev->dev); if (rspi_pd && rspi_pd->num_chipselect) ctlr->num_chipselect = rspi_pd->num_chipselect; else ctlr->num_chipselect = 2; /* default */ } rspi = spi_controller_get_devdata(ctlr); platform_set_drvdata(pdev, rspi); rspi->ops = ops; rspi->ctlr = ctlr; res = platform_get_resource(pdev, IORESOURCE_MEM, 0); rspi->addr = devm_ioremap_resource(&pdev->dev, res); if (IS_ERR(rspi->addr)) { ret = PTR_ERR(rspi->addr); goto error1; } rspi->clk = devm_clk_get(&pdev->dev, NULL); if (IS_ERR(rspi->clk)) { dev_err(&pdev->dev, "cannot get clock\n"); ret = PTR_ERR(rspi->clk); goto error1; } rspi->pdev = pdev; pm_runtime_enable(&pdev->dev); init_waitqueue_head(&rspi->wait); spin_lock_init(&rspi->lock); ctlr->bus_num = pdev->id; ctlr->setup = rspi_setup; ctlr->auto_runtime_pm = true; ctlr->transfer_one = ops->transfer_one; ctlr->prepare_message = rspi_prepare_message; ctlr->unprepare_message = rspi_unprepare_message; ctlr->mode_bits = SPI_CPHA | SPI_CPOL | SPI_CS_HIGH | SPI_LSB_FIRST | SPI_LOOP | ops->extra_mode_bits; clksrc = clk_get_rate(rspi->clk); ctlr->min_speed_hz = DIV_ROUND_UP(clksrc, ops->max_div); ctlr->max_speed_hz = DIV_ROUND_UP(clksrc, ops->min_div); ctlr->flags = ops->flags; ctlr->dev.of_node = pdev->dev.of_node; ctlr->use_gpio_descriptors = true; ctlr->max_native_cs = rspi->ops->num_hw_ss; ret = platform_get_irq_byname_optional(pdev, "rx"); if (ret < 0) { ret = platform_get_irq_byname_optional(pdev, "mux"); if (ret < 0) ret = platform_get_irq(pdev, 0); if (ret >= 0) rspi->rx_irq = rspi->tx_irq = ret; } else { rspi->rx_irq = ret; ret = platform_get_irq_byname(pdev, "tx"); if (ret >= 0) rspi->tx_irq = ret; } if (rspi->rx_irq == rspi->tx_irq) { /* Single multiplexed interrupt */ ret = rspi_request_irq(&pdev->dev, rspi->rx_irq, rspi_irq_mux, "mux", rspi); } else { /* Multi-interrupt mode, only SPRI and SPTI are used */ ret = rspi_request_irq(&pdev->dev, rspi->rx_irq, rspi_irq_rx, "rx", rspi); if (!ret) ret = rspi_request_irq(&pdev->dev, rspi->tx_irq, rspi_irq_tx, "tx", rspi); } if (ret < 0) { dev_err(&pdev->dev, "request_irq error\n"); goto error2; } ret = rspi_request_dma(&pdev->dev, ctlr, res); if (ret < 0) dev_warn(&pdev->dev, "DMA not available, using PIO\n"); ret = devm_spi_register_controller(&pdev->dev, ctlr); if (ret < 0) { dev_err(&pdev->dev, "devm_spi_register_controller error.\n"); goto error3; } dev_info(&pdev->dev, "probed\n"); return 0; error3: rspi_release_dma(ctlr); error2: pm_runtime_disable(&pdev->dev); error1: spi_controller_put(ctlr); return ret; } static const struct platform_device_id spi_driver_ids[] = { { "rspi", (kernel_ulong_t)&rspi_ops }, {}, }; MODULE_DEVICE_TABLE(platform, spi_driver_ids); #ifdef CONFIG_PM_SLEEP static int rspi_suspend(struct device *dev) { struct rspi_data *rspi = dev_get_drvdata(dev); return spi_controller_suspend(rspi->ctlr); } static int rspi_resume(struct device *dev) { struct rspi_data *rspi = dev_get_drvdata(dev); return spi_controller_resume(rspi->ctlr); } static SIMPLE_DEV_PM_OPS(rspi_pm_ops, rspi_suspend, rspi_resume); #define DEV_PM_OPS &rspi_pm_ops #else #define DEV_PM_OPS NULL #endif /* CONFIG_PM_SLEEP */ static struct platform_driver rspi_driver = { .probe = rspi_probe, .remove = rspi_remove, .id_table = spi_driver_ids, .driver = { .name = "renesas_spi", .pm = DEV_PM_OPS, .of_match_table = of_match_ptr(rspi_of_match), }, }; module_platform_driver(rspi_driver); MODULE_DESCRIPTION("Renesas RSPI bus driver"); MODULE_LICENSE("GPL v2"); MODULE_AUTHOR("Yoshihiro Shimoda");