From 6c710c0cb6725bdbe647b958756685aed0295936 Mon Sep 17 00:00:00 2001 From: Serge Semin Date: Fri, 29 May 2020 16:11:59 +0300 Subject: spi: dw: Move Non-DMA code to the DW PCIe-SPI driver This is a preparation patch before adding the DW DMA support into the DW SPI MMIO driver. We need to unpin the Non-DMA-specific code from the intended to be generic DW APB SSI DMA code. This isn't that hard, since the most part of the spi-dw-mid.c driver in fact implements a generic DMA interface for the DW SPI controller driver. The only Intel MID specifics concern getting the max frequency from the MRST Clock Control Unit and fetching the DMA controller channels from corresponding PCIe DMA controller. Since first one is related with the SPI interface configuration we moved it' implementation into the DW PCIe-SPI driver module. After that former spi-dw-mid.c file can be just renamed to be the DW SPI DMA module optionally compiled in to the DW APB SSI core driver. Co-developed-by: Georgy Vlasov Co-developed-by: Ramil Zaripov Signed-off-by: Georgy Vlasov Signed-off-by: Ramil Zaripov Signed-off-by: Serge Semin Reviewed-by: Andy Shevchenko Cc: Alexey Malahov Cc: Thomas Bogendoerfer Cc: Arnd Bergmann Cc: Feng Tang Cc: Rob Herring Cc: linux-mips@vger.kernel.org Cc: devicetree@vger.kernel.org Link: https://lore.kernel.org/r/20200529131205.31838-11-Sergey.Semin@baikalelectronics.ru Signed-off-by: Mark Brown --- drivers/spi/Kconfig | 8 +- drivers/spi/Makefile | 4 +- drivers/spi/spi-dw-dma.c | 481 ++++++++++++++++++++++++++++++++++++++++++ drivers/spi/spi-dw-mid.c | 529 ----------------------------------------------- drivers/spi/spi-dw-pci.c | 50 ++++- drivers/spi/spi-dw.h | 14 +- 6 files changed, 545 insertions(+), 541 deletions(-) create mode 100644 drivers/spi/spi-dw-dma.c delete mode 100644 drivers/spi/spi-dw-mid.c (limited to 'drivers/spi') diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig index 099d6a75a371..73d508eb4871 100644 --- a/drivers/spi/Kconfig +++ b/drivers/spi/Kconfig @@ -226,14 +226,14 @@ config SPI_DESIGNWARE help general driver for SPI controller core from DesignWare +config SPI_DW_DMA + bool "DMA support for DW SPI controller" + depends on SPI_DESIGNWARE && DW_DMAC_PCI + config SPI_DW_PCI tristate "PCI interface driver for DW SPI core" depends on SPI_DESIGNWARE && PCI -config SPI_DW_MID_DMA - bool "DMA support for DW SPI controller on Intel MID platform" - depends on SPI_DW_PCI && DW_DMAC_PCI - config SPI_DW_MMIO tristate "Memory-mapped io interface driver for DW SPI core" depends on SPI_DESIGNWARE diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile index 840a5a1c655e..d2e41d3d464a 100644 --- a/drivers/spi/Makefile +++ b/drivers/spi/Makefile @@ -37,9 +37,9 @@ obj-$(CONFIG_SPI_DAVINCI) += spi-davinci.o obj-$(CONFIG_SPI_DLN2) += spi-dln2.o obj-$(CONFIG_SPI_DESIGNWARE) += spi-dw.o spi-dw-y := spi-dw-core.o +spi-dw-$(CONFIG_SPI_DW_DMA) += spi-dw-dma.o obj-$(CONFIG_SPI_DW_MMIO) += spi-dw-mmio.o -obj-$(CONFIG_SPI_DW_PCI) += spi-dw-midpci.o -spi-dw-midpci-objs := spi-dw-pci.o spi-dw-mid.o +obj-$(CONFIG_SPI_DW_PCI) += spi-dw-pci.o obj-$(CONFIG_SPI_EFM32) += spi-efm32.o obj-$(CONFIG_SPI_EP93XX) += spi-ep93xx.o obj-$(CONFIG_SPI_FALCON) += spi-falcon.o diff --git a/drivers/spi/spi-dw-dma.c b/drivers/spi/spi-dw-dma.c new file mode 100644 index 000000000000..7ae31682b5de --- /dev/null +++ b/drivers/spi/spi-dw-dma.c @@ -0,0 +1,481 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Special handling for DW DMA core + * + * Copyright (c) 2009, 2014 Intel Corporation. + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "spi-dw.h" + +#define WAIT_RETRIES 5 +#define RX_BUSY 0 +#define RX_BURST_LEVEL 16 +#define TX_BUSY 1 +#define TX_BURST_LEVEL 16 + +static bool mid_spi_dma_chan_filter(struct dma_chan *chan, void *param) +{ + struct dw_dma_slave *s = param; + + if (s->dma_dev != chan->device->dev) + return false; + + chan->private = s; + return true; +} + +static void mid_spi_maxburst_init(struct dw_spi *dws) +{ + struct dma_slave_caps caps; + u32 max_burst, def_burst; + int ret; + + def_burst = dws->fifo_len / 2; + + ret = dma_get_slave_caps(dws->rxchan, &caps); + if (!ret && caps.max_burst) + max_burst = caps.max_burst; + else + max_burst = RX_BURST_LEVEL; + + dws->rxburst = min(max_burst, def_burst); + + ret = dma_get_slave_caps(dws->txchan, &caps); + if (!ret && caps.max_burst) + max_burst = caps.max_burst; + else + max_burst = TX_BURST_LEVEL; + + dws->txburst = min(max_burst, def_burst); +} + +static int mid_spi_dma_init_mfld(struct device *dev, struct dw_spi *dws) +{ + struct dw_dma_slave slave = { + .src_id = 0, + .dst_id = 0 + }; + struct pci_dev *dma_dev; + dma_cap_mask_t mask; + + /* + * Get pci device for DMA controller, currently it could only + * be the DMA controller of Medfield + */ + dma_dev = pci_get_device(PCI_VENDOR_ID_INTEL, 0x0827, NULL); + if (!dma_dev) + return -ENODEV; + + dma_cap_zero(mask); + dma_cap_set(DMA_SLAVE, mask); + + /* 1. Init rx channel */ + slave.dma_dev = &dma_dev->dev; + dws->rxchan = dma_request_channel(mask, mid_spi_dma_chan_filter, &slave); + if (!dws->rxchan) + goto err_exit; + + /* 2. Init tx channel */ + slave.dst_id = 1; + dws->txchan = dma_request_channel(mask, mid_spi_dma_chan_filter, &slave); + if (!dws->txchan) + goto free_rxchan; + + dws->master->dma_rx = dws->rxchan; + dws->master->dma_tx = dws->txchan; + + init_completion(&dws->dma_completion); + + mid_spi_maxburst_init(dws); + + return 0; + +free_rxchan: + dma_release_channel(dws->rxchan); + dws->rxchan = NULL; +err_exit: + return -EBUSY; +} + +static int mid_spi_dma_init_generic(struct device *dev, struct dw_spi *dws) +{ + dws->rxchan = dma_request_slave_channel(dev, "rx"); + if (!dws->rxchan) + return -ENODEV; + + dws->txchan = dma_request_slave_channel(dev, "tx"); + if (!dws->txchan) { + dma_release_channel(dws->rxchan); + dws->rxchan = NULL; + return -ENODEV; + } + + dws->master->dma_rx = dws->rxchan; + dws->master->dma_tx = dws->txchan; + + init_completion(&dws->dma_completion); + + mid_spi_maxburst_init(dws); + + return 0; +} + +static void mid_spi_dma_exit(struct dw_spi *dws) +{ + if (dws->txchan) { + dmaengine_terminate_sync(dws->txchan); + dma_release_channel(dws->txchan); + } + + if (dws->rxchan) { + dmaengine_terminate_sync(dws->rxchan); + dma_release_channel(dws->rxchan); + } + + dw_writel(dws, DW_SPI_DMACR, 0); +} + +static irqreturn_t dma_transfer(struct dw_spi *dws) +{ + u16 irq_status = dw_readl(dws, DW_SPI_ISR); + + if (!irq_status) + return IRQ_NONE; + + dw_readl(dws, DW_SPI_ICR); + spi_reset_chip(dws); + + dev_err(&dws->master->dev, "%s: FIFO overrun/underrun\n", __func__); + dws->master->cur_msg->status = -EIO; + complete(&dws->dma_completion); + return IRQ_HANDLED; +} + +static bool mid_spi_can_dma(struct spi_controller *master, + struct spi_device *spi, struct spi_transfer *xfer) +{ + struct dw_spi *dws = spi_controller_get_devdata(master); + + return xfer->len > dws->fifo_len; +} + +static enum dma_slave_buswidth convert_dma_width(u8 n_bytes) { + if (n_bytes == 1) + return DMA_SLAVE_BUSWIDTH_1_BYTE; + else if (n_bytes == 2) + return DMA_SLAVE_BUSWIDTH_2_BYTES; + + return DMA_SLAVE_BUSWIDTH_UNDEFINED; +} + +static int dw_spi_dma_wait(struct dw_spi *dws, struct spi_transfer *xfer) +{ + unsigned long long ms; + + ms = xfer->len * MSEC_PER_SEC * BITS_PER_BYTE; + do_div(ms, xfer->effective_speed_hz); + ms += ms + 200; + + if (ms > UINT_MAX) + ms = UINT_MAX; + + ms = wait_for_completion_timeout(&dws->dma_completion, + msecs_to_jiffies(ms)); + + if (ms == 0) { + dev_err(&dws->master->cur_msg->spi->dev, + "DMA transaction timed out\n"); + return -ETIMEDOUT; + } + + return 0; +} + +static inline bool dw_spi_dma_tx_busy(struct dw_spi *dws) +{ + return !(dw_readl(dws, DW_SPI_SR) & SR_TF_EMPT); +} + +static int dw_spi_dma_wait_tx_done(struct dw_spi *dws, + struct spi_transfer *xfer) +{ + int retry = WAIT_RETRIES; + struct spi_delay delay; + u32 nents; + + nents = dw_readl(dws, DW_SPI_TXFLR); + delay.unit = SPI_DELAY_UNIT_SCK; + delay.value = nents * dws->n_bytes * BITS_PER_BYTE; + + while (dw_spi_dma_tx_busy(dws) && retry--) + spi_delay_exec(&delay, xfer); + + if (retry < 0) { + dev_err(&dws->master->dev, "Tx hanged up\n"); + return -EIO; + } + + return 0; +} + +/* + * dws->dma_chan_busy is set before the dma transfer starts, callback for tx + * channel will clear a corresponding bit. + */ +static void dw_spi_dma_tx_done(void *arg) +{ + struct dw_spi *dws = arg; + + clear_bit(TX_BUSY, &dws->dma_chan_busy); + if (test_bit(RX_BUSY, &dws->dma_chan_busy)) + return; + + dw_writel(dws, DW_SPI_DMACR, 0); + complete(&dws->dma_completion); +} + +static struct dma_async_tx_descriptor *dw_spi_dma_prepare_tx(struct dw_spi *dws, + struct spi_transfer *xfer) +{ + struct dma_slave_config txconf; + struct dma_async_tx_descriptor *txdesc; + + if (!xfer->tx_buf) + return NULL; + + memset(&txconf, 0, sizeof(txconf)); + txconf.direction = DMA_MEM_TO_DEV; + txconf.dst_addr = dws->dma_addr; + txconf.dst_maxburst = dws->txburst; + txconf.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; + txconf.dst_addr_width = convert_dma_width(dws->n_bytes); + txconf.device_fc = false; + + dmaengine_slave_config(dws->txchan, &txconf); + + txdesc = dmaengine_prep_slave_sg(dws->txchan, + xfer->tx_sg.sgl, + xfer->tx_sg.nents, + DMA_MEM_TO_DEV, + DMA_PREP_INTERRUPT | DMA_CTRL_ACK); + if (!txdesc) + return NULL; + + txdesc->callback = dw_spi_dma_tx_done; + txdesc->callback_param = dws; + + return txdesc; +} + +static inline bool dw_spi_dma_rx_busy(struct dw_spi *dws) +{ + return !!(dw_readl(dws, DW_SPI_SR) & SR_RF_NOT_EMPT); +} + +static int dw_spi_dma_wait_rx_done(struct dw_spi *dws) +{ + int retry = WAIT_RETRIES; + struct spi_delay delay; + unsigned long ns, us; + u32 nents; + + /* + * It's unlikely that DMA engine is still doing the data fetching, but + * if it's let's give it some reasonable time. The timeout calculation + * is based on the synchronous APB/SSI reference clock rate, on a + * number of data entries left in the Rx FIFO, times a number of clock + * periods normally needed for a single APB read/write transaction + * without PREADY signal utilized (which is true for the DW APB SSI + * controller). + */ + nents = dw_readl(dws, DW_SPI_RXFLR); + ns = 4U * NSEC_PER_SEC / dws->max_freq * nents; + if (ns <= NSEC_PER_USEC) { + delay.unit = SPI_DELAY_UNIT_NSECS; + delay.value = ns; + } else { + us = DIV_ROUND_UP(ns, NSEC_PER_USEC); + delay.unit = SPI_DELAY_UNIT_USECS; + delay.value = clamp_val(us, 0, USHRT_MAX); + } + + while (dw_spi_dma_rx_busy(dws) && retry--) + spi_delay_exec(&delay, NULL); + + if (retry < 0) { + dev_err(&dws->master->dev, "Rx hanged up\n"); + return -EIO; + } + + return 0; +} + +/* + * dws->dma_chan_busy is set before the dma transfer starts, callback for rx + * channel will clear a corresponding bit. + */ +static void dw_spi_dma_rx_done(void *arg) +{ + struct dw_spi *dws = arg; + + clear_bit(RX_BUSY, &dws->dma_chan_busy); + if (test_bit(TX_BUSY, &dws->dma_chan_busy)) + return; + + dw_writel(dws, DW_SPI_DMACR, 0); + complete(&dws->dma_completion); +} + +static struct dma_async_tx_descriptor *dw_spi_dma_prepare_rx(struct dw_spi *dws, + struct spi_transfer *xfer) +{ + struct dma_slave_config rxconf; + struct dma_async_tx_descriptor *rxdesc; + + if (!xfer->rx_buf) + return NULL; + + memset(&rxconf, 0, sizeof(rxconf)); + rxconf.direction = DMA_DEV_TO_MEM; + rxconf.src_addr = dws->dma_addr; + rxconf.src_maxburst = dws->rxburst; + rxconf.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; + rxconf.src_addr_width = convert_dma_width(dws->n_bytes); + rxconf.device_fc = false; + + dmaengine_slave_config(dws->rxchan, &rxconf); + + rxdesc = dmaengine_prep_slave_sg(dws->rxchan, + xfer->rx_sg.sgl, + xfer->rx_sg.nents, + DMA_DEV_TO_MEM, + DMA_PREP_INTERRUPT | DMA_CTRL_ACK); + if (!rxdesc) + return NULL; + + rxdesc->callback = dw_spi_dma_rx_done; + rxdesc->callback_param = dws; + + return rxdesc; +} + +static int mid_spi_dma_setup(struct dw_spi *dws, struct spi_transfer *xfer) +{ + u16 imr = 0, dma_ctrl = 0; + + dw_writel(dws, DW_SPI_DMARDLR, dws->rxburst - 1); + dw_writel(dws, DW_SPI_DMATDLR, dws->fifo_len - dws->txburst); + + if (xfer->tx_buf) { + dma_ctrl |= SPI_DMA_TDMAE; + imr |= SPI_INT_TXOI; + } + if (xfer->rx_buf) { + dma_ctrl |= SPI_DMA_RDMAE; + imr |= SPI_INT_RXUI | SPI_INT_RXOI; + } + dw_writel(dws, DW_SPI_DMACR, dma_ctrl); + + /* Set the interrupt mask */ + spi_umask_intr(dws, imr); + + reinit_completion(&dws->dma_completion); + + dws->transfer_handler = dma_transfer; + + return 0; +} + +static int mid_spi_dma_transfer(struct dw_spi *dws, struct spi_transfer *xfer) +{ + struct dma_async_tx_descriptor *txdesc, *rxdesc; + int ret; + + /* Prepare the TX dma transfer */ + txdesc = dw_spi_dma_prepare_tx(dws, xfer); + + /* Prepare the RX dma transfer */ + rxdesc = dw_spi_dma_prepare_rx(dws, xfer); + + /* rx must be started before tx due to spi instinct */ + if (rxdesc) { + set_bit(RX_BUSY, &dws->dma_chan_busy); + dmaengine_submit(rxdesc); + dma_async_issue_pending(dws->rxchan); + } + + if (txdesc) { + set_bit(TX_BUSY, &dws->dma_chan_busy); + dmaengine_submit(txdesc); + dma_async_issue_pending(dws->txchan); + } + + ret = dw_spi_dma_wait(dws, xfer); + if (ret) + return ret; + + if (txdesc && dws->master->cur_msg->status == -EINPROGRESS) { + ret = dw_spi_dma_wait_tx_done(dws, xfer); + if (ret) + return ret; + } + + if (rxdesc && dws->master->cur_msg->status == -EINPROGRESS) + ret = dw_spi_dma_wait_rx_done(dws); + + return ret; +} + +static void mid_spi_dma_stop(struct dw_spi *dws) +{ + if (test_bit(TX_BUSY, &dws->dma_chan_busy)) { + dmaengine_terminate_sync(dws->txchan); + clear_bit(TX_BUSY, &dws->dma_chan_busy); + } + if (test_bit(RX_BUSY, &dws->dma_chan_busy)) { + dmaengine_terminate_sync(dws->rxchan); + clear_bit(RX_BUSY, &dws->dma_chan_busy); + } + + dw_writel(dws, DW_SPI_DMACR, 0); +} + +static const struct dw_spi_dma_ops mfld_dma_ops = { + .dma_init = mid_spi_dma_init_mfld, + .dma_exit = mid_spi_dma_exit, + .dma_setup = mid_spi_dma_setup, + .can_dma = mid_spi_can_dma, + .dma_transfer = mid_spi_dma_transfer, + .dma_stop = mid_spi_dma_stop, +}; + +void dw_spi_mid_setup_dma_mfld(struct dw_spi *dws) +{ + dws->dma_ops = &mfld_dma_ops; +} +EXPORT_SYMBOL_GPL(dw_spi_mid_setup_dma_mfld); + +static const struct dw_spi_dma_ops generic_dma_ops = { + .dma_init = mid_spi_dma_init_generic, + .dma_exit = mid_spi_dma_exit, + .dma_setup = mid_spi_dma_setup, + .can_dma = mid_spi_can_dma, + .dma_transfer = mid_spi_dma_transfer, + .dma_stop = mid_spi_dma_stop, +}; + +void dw_spi_mid_setup_dma_generic(struct dw_spi *dws) +{ + dws->dma_ops = &generic_dma_ops; +} +EXPORT_SYMBOL_GPL(dw_spi_mid_setup_dma_generic); diff --git a/drivers/spi/spi-dw-mid.c b/drivers/spi/spi-dw-mid.c deleted file mode 100644 index 1cf9e3ffe07b..000000000000 --- a/drivers/spi/spi-dw-mid.c +++ /dev/null @@ -1,529 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0-only -/* - * Special handling for DW core on Intel MID platform - * - * Copyright (c) 2009, 2014 Intel Corporation. - */ - -#include -#include - -#include "spi-dw.h" - -#ifdef CONFIG_SPI_DW_MID_DMA -#include -#include -#include -#include -#include -#include -#include - -#define WAIT_RETRIES 5 -#define RX_BUSY 0 -#define RX_BURST_LEVEL 16 -#define TX_BUSY 1 -#define TX_BURST_LEVEL 16 - -static bool mid_spi_dma_chan_filter(struct dma_chan *chan, void *param) -{ - struct dw_dma_slave *s = param; - - if (s->dma_dev != chan->device->dev) - return false; - - chan->private = s; - return true; -} - -static void mid_spi_maxburst_init(struct dw_spi *dws) -{ - struct dma_slave_caps caps; - u32 max_burst, def_burst; - int ret; - - def_burst = dws->fifo_len / 2; - - ret = dma_get_slave_caps(dws->rxchan, &caps); - if (!ret && caps.max_burst) - max_burst = caps.max_burst; - else - max_burst = RX_BURST_LEVEL; - - dws->rxburst = min(max_burst, def_burst); - - ret = dma_get_slave_caps(dws->txchan, &caps); - if (!ret && caps.max_burst) - max_burst = caps.max_burst; - else - max_burst = TX_BURST_LEVEL; - - dws->txburst = min(max_burst, def_burst); -} - -static int mid_spi_dma_init_mfld(struct device *dev, struct dw_spi *dws) -{ - struct dw_dma_slave slave = { - .src_id = 0, - .dst_id = 0 - }; - struct pci_dev *dma_dev; - dma_cap_mask_t mask; - - /* - * Get pci device for DMA controller, currently it could only - * be the DMA controller of Medfield - */ - dma_dev = pci_get_device(PCI_VENDOR_ID_INTEL, 0x0827, NULL); - if (!dma_dev) - return -ENODEV; - - dma_cap_zero(mask); - dma_cap_set(DMA_SLAVE, mask); - - /* 1. Init rx channel */ - slave.dma_dev = &dma_dev->dev; - dws->rxchan = dma_request_channel(mask, mid_spi_dma_chan_filter, &slave); - if (!dws->rxchan) - goto err_exit; - - /* 2. Init tx channel */ - slave.dst_id = 1; - dws->txchan = dma_request_channel(mask, mid_spi_dma_chan_filter, &slave); - if (!dws->txchan) - goto free_rxchan; - - dws->master->dma_rx = dws->rxchan; - dws->master->dma_tx = dws->txchan; - - init_completion(&dws->dma_completion); - - mid_spi_maxburst_init(dws); - - return 0; - -free_rxchan: - dma_release_channel(dws->rxchan); - dws->rxchan = NULL; -err_exit: - return -EBUSY; -} - -static int mid_spi_dma_init_generic(struct device *dev, struct dw_spi *dws) -{ - dws->rxchan = dma_request_slave_channel(dev, "rx"); - if (!dws->rxchan) - return -ENODEV; - - dws->txchan = dma_request_slave_channel(dev, "tx"); - if (!dws->txchan) { - dma_release_channel(dws->rxchan); - dws->rxchan = NULL; - return -ENODEV; - } - - dws->master->dma_rx = dws->rxchan; - dws->master->dma_tx = dws->txchan; - - init_completion(&dws->dma_completion); - - mid_spi_maxburst_init(dws); - - return 0; -} - -static void mid_spi_dma_exit(struct dw_spi *dws) -{ - if (dws->txchan) { - dmaengine_terminate_sync(dws->txchan); - dma_release_channel(dws->txchan); - } - - if (dws->rxchan) { - dmaengine_terminate_sync(dws->rxchan); - dma_release_channel(dws->rxchan); - } - - dw_writel(dws, DW_SPI_DMACR, 0); -} - -static irqreturn_t dma_transfer(struct dw_spi *dws) -{ - u16 irq_status = dw_readl(dws, DW_SPI_ISR); - - if (!irq_status) - return IRQ_NONE; - - dw_readl(dws, DW_SPI_ICR); - spi_reset_chip(dws); - - dev_err(&dws->master->dev, "%s: FIFO overrun/underrun\n", __func__); - dws->master->cur_msg->status = -EIO; - complete(&dws->dma_completion); - return IRQ_HANDLED; -} - -static bool mid_spi_can_dma(struct spi_controller *master, - struct spi_device *spi, struct spi_transfer *xfer) -{ - struct dw_spi *dws = spi_controller_get_devdata(master); - - return xfer->len > dws->fifo_len; -} - -static enum dma_slave_buswidth convert_dma_width(u8 n_bytes) { - if (n_bytes == 1) - return DMA_SLAVE_BUSWIDTH_1_BYTE; - else if (n_bytes == 2) - return DMA_SLAVE_BUSWIDTH_2_BYTES; - - return DMA_SLAVE_BUSWIDTH_UNDEFINED; -} - -static int dw_spi_dma_wait(struct dw_spi *dws, struct spi_transfer *xfer) -{ - unsigned long long ms; - - ms = xfer->len * MSEC_PER_SEC * BITS_PER_BYTE; - do_div(ms, xfer->effective_speed_hz); - ms += ms + 200; - - if (ms > UINT_MAX) - ms = UINT_MAX; - - ms = wait_for_completion_timeout(&dws->dma_completion, - msecs_to_jiffies(ms)); - - if (ms == 0) { - dev_err(&dws->master->cur_msg->spi->dev, - "DMA transaction timed out\n"); - return -ETIMEDOUT; - } - - return 0; -} - -static inline bool dw_spi_dma_tx_busy(struct dw_spi *dws) -{ - return !(dw_readl(dws, DW_SPI_SR) & SR_TF_EMPT); -} - -static int dw_spi_dma_wait_tx_done(struct dw_spi *dws, - struct spi_transfer *xfer) -{ - int retry = WAIT_RETRIES; - struct spi_delay delay; - u32 nents; - - nents = dw_readl(dws, DW_SPI_TXFLR); - delay.unit = SPI_DELAY_UNIT_SCK; - delay.value = nents * dws->n_bytes * BITS_PER_BYTE; - - while (dw_spi_dma_tx_busy(dws) && retry--) - spi_delay_exec(&delay, xfer); - - if (retry < 0) { - dev_err(&dws->master->dev, "Tx hanged up\n"); - return -EIO; - } - - return 0; -} - -/* - * dws->dma_chan_busy is set before the dma transfer starts, callback for tx - * channel will clear a corresponding bit. - */ -static void dw_spi_dma_tx_done(void *arg) -{ - struct dw_spi *dws = arg; - - clear_bit(TX_BUSY, &dws->dma_chan_busy); - if (test_bit(RX_BUSY, &dws->dma_chan_busy)) - return; - - dw_writel(dws, DW_SPI_DMACR, 0); - complete(&dws->dma_completion); -} - -static struct dma_async_tx_descriptor *dw_spi_dma_prepare_tx(struct dw_spi *dws, - struct spi_transfer *xfer) -{ - struct dma_slave_config txconf; - struct dma_async_tx_descriptor *txdesc; - - if (!xfer->tx_buf) - return NULL; - - memset(&txconf, 0, sizeof(txconf)); - txconf.direction = DMA_MEM_TO_DEV; - txconf.dst_addr = dws->dma_addr; - txconf.dst_maxburst = dws->txburst; - txconf.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; - txconf.dst_addr_width = convert_dma_width(dws->n_bytes); - txconf.device_fc = false; - - dmaengine_slave_config(dws->txchan, &txconf); - - txdesc = dmaengine_prep_slave_sg(dws->txchan, - xfer->tx_sg.sgl, - xfer->tx_sg.nents, - DMA_MEM_TO_DEV, - DMA_PREP_INTERRUPT | DMA_CTRL_ACK); - if (!txdesc) - return NULL; - - txdesc->callback = dw_spi_dma_tx_done; - txdesc->callback_param = dws; - - return txdesc; -} - -static inline bool dw_spi_dma_rx_busy(struct dw_spi *dws) -{ - return !!(dw_readl(dws, DW_SPI_SR) & SR_RF_NOT_EMPT); -} - -static int dw_spi_dma_wait_rx_done(struct dw_spi *dws) -{ - int retry = WAIT_RETRIES; - struct spi_delay delay; - unsigned long ns, us; - u32 nents; - - /* - * It's unlikely that DMA engine is still doing the data fetching, but - * if it's let's give it some reasonable time. The timeout calculation - * is based on the synchronous APB/SSI reference clock rate, on a - * number of data entries left in the Rx FIFO, times a number of clock - * periods normally needed for a single APB read/write transaction - * without PREADY signal utilized (which is true for the DW APB SSI - * controller). - */ - nents = dw_readl(dws, DW_SPI_RXFLR); - ns = 4U * NSEC_PER_SEC / dws->max_freq * nents; - if (ns <= NSEC_PER_USEC) { - delay.unit = SPI_DELAY_UNIT_NSECS; - delay.value = ns; - } else { - us = DIV_ROUND_UP(ns, NSEC_PER_USEC); - delay.unit = SPI_DELAY_UNIT_USECS; - delay.value = clamp_val(us, 0, USHRT_MAX); - } - - while (dw_spi_dma_rx_busy(dws) && retry--) - spi_delay_exec(&delay, NULL); - - if (retry < 0) { - dev_err(&dws->master->dev, "Rx hanged up\n"); - return -EIO; - } - - return 0; -} - -/* - * dws->dma_chan_busy is set before the dma transfer starts, callback for rx - * channel will clear a corresponding bit. - */ -static void dw_spi_dma_rx_done(void *arg) -{ - struct dw_spi *dws = arg; - - clear_bit(RX_BUSY, &dws->dma_chan_busy); - if (test_bit(TX_BUSY, &dws->dma_chan_busy)) - return; - - dw_writel(dws, DW_SPI_DMACR, 0); - complete(&dws->dma_completion); -} - -static struct dma_async_tx_descriptor *dw_spi_dma_prepare_rx(struct dw_spi *dws, - struct spi_transfer *xfer) -{ - struct dma_slave_config rxconf; - struct dma_async_tx_descriptor *rxdesc; - - if (!xfer->rx_buf) - return NULL; - - memset(&rxconf, 0, sizeof(rxconf)); - rxconf.direction = DMA_DEV_TO_MEM; - rxconf.src_addr = dws->dma_addr; - rxconf.src_maxburst = dws->rxburst; - rxconf.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; - rxconf.src_addr_width = convert_dma_width(dws->n_bytes); - rxconf.device_fc = false; - - dmaengine_slave_config(dws->rxchan, &rxconf); - - rxdesc = dmaengine_prep_slave_sg(dws->rxchan, - xfer->rx_sg.sgl, - xfer->rx_sg.nents, - DMA_DEV_TO_MEM, - DMA_PREP_INTERRUPT | DMA_CTRL_ACK); - if (!rxdesc) - return NULL; - - rxdesc->callback = dw_spi_dma_rx_done; - rxdesc->callback_param = dws; - - return rxdesc; -} - -static int mid_spi_dma_setup(struct dw_spi *dws, struct spi_transfer *xfer) -{ - u16 imr = 0, dma_ctrl = 0; - - dw_writel(dws, DW_SPI_DMARDLR, dws->rxburst - 1); - dw_writel(dws, DW_SPI_DMATDLR, dws->fifo_len - dws->txburst); - - if (xfer->tx_buf) { - dma_ctrl |= SPI_DMA_TDMAE; - imr |= SPI_INT_TXOI; - } - if (xfer->rx_buf) { - dma_ctrl |= SPI_DMA_RDMAE; - imr |= SPI_INT_RXUI | SPI_INT_RXOI; - } - dw_writel(dws, DW_SPI_DMACR, dma_ctrl); - - /* Set the interrupt mask */ - spi_umask_intr(dws, imr); - - reinit_completion(&dws->dma_completion); - - dws->transfer_handler = dma_transfer; - - return 0; -} - -static int mid_spi_dma_transfer(struct dw_spi *dws, struct spi_transfer *xfer) -{ - struct dma_async_tx_descriptor *txdesc, *rxdesc; - int ret; - - /* Prepare the TX dma transfer */ - txdesc = dw_spi_dma_prepare_tx(dws, xfer); - - /* Prepare the RX dma transfer */ - rxdesc = dw_spi_dma_prepare_rx(dws, xfer); - - /* rx must be started before tx due to spi instinct */ - if (rxdesc) { - set_bit(RX_BUSY, &dws->dma_chan_busy); - dmaengine_submit(rxdesc); - dma_async_issue_pending(dws->rxchan); - } - - if (txdesc) { - set_bit(TX_BUSY, &dws->dma_chan_busy); - dmaengine_submit(txdesc); - dma_async_issue_pending(dws->txchan); - } - - ret = dw_spi_dma_wait(dws, xfer); - if (ret) - return ret; - - if (txdesc && dws->master->cur_msg->status == -EINPROGRESS) { - ret = dw_spi_dma_wait_tx_done(dws, xfer); - if (ret) - return ret; - } - - if (rxdesc && dws->master->cur_msg->status == -EINPROGRESS) - ret = dw_spi_dma_wait_rx_done(dws); - - return ret; -} - -static void mid_spi_dma_stop(struct dw_spi *dws) -{ - if (test_bit(TX_BUSY, &dws->dma_chan_busy)) { - dmaengine_terminate_sync(dws->txchan); - clear_bit(TX_BUSY, &dws->dma_chan_busy); - } - if (test_bit(RX_BUSY, &dws->dma_chan_busy)) { - dmaengine_terminate_sync(dws->rxchan); - clear_bit(RX_BUSY, &dws->dma_chan_busy); - } - - dw_writel(dws, DW_SPI_DMACR, 0); -} - -static const struct dw_spi_dma_ops mfld_dma_ops = { - .dma_init = mid_spi_dma_init_mfld, - .dma_exit = mid_spi_dma_exit, - .dma_setup = mid_spi_dma_setup, - .can_dma = mid_spi_can_dma, - .dma_transfer = mid_spi_dma_transfer, - .dma_stop = mid_spi_dma_stop, -}; - -static void dw_spi_mid_setup_dma_mfld(struct dw_spi *dws) -{ - dws->dma_ops = &mfld_dma_ops; -} - -static const struct dw_spi_dma_ops generic_dma_ops = { - .dma_init = mid_spi_dma_init_generic, - .dma_exit = mid_spi_dma_exit, - .dma_setup = mid_spi_dma_setup, - .can_dma = mid_spi_can_dma, - .dma_transfer = mid_spi_dma_transfer, - .dma_stop = mid_spi_dma_stop, -}; - -static void dw_spi_mid_setup_dma_generic(struct dw_spi *dws) -{ - dws->dma_ops = &generic_dma_ops; -} -#else /* CONFIG_SPI_DW_MID_DMA */ -static inline void dw_spi_mid_setup_dma_mfld(struct dw_spi *dws) {} -static inline void dw_spi_mid_setup_dma_generic(struct dw_spi *dws) {} -#endif - -/* Some specific info for SPI0 controller on Intel MID */ - -/* HW info for MRST Clk Control Unit, 32b reg per controller */ -#define MRST_SPI_CLK_BASE 100000000 /* 100m */ -#define MRST_CLK_SPI_REG 0xff11d86c -#define CLK_SPI_BDIV_OFFSET 0 -#define CLK_SPI_BDIV_MASK 0x00000007 -#define CLK_SPI_CDIV_OFFSET 9 -#define CLK_SPI_CDIV_MASK 0x00000e00 -#define CLK_SPI_DISABLE_OFFSET 8 - -int dw_spi_mid_init_mfld(struct dw_spi *dws) -{ - void __iomem *clk_reg; - u32 clk_cdiv; - - clk_reg = ioremap(MRST_CLK_SPI_REG, 16); - if (!clk_reg) - return -ENOMEM; - - /* Get SPI controller operating freq info */ - clk_cdiv = readl(clk_reg + dws->bus_num * sizeof(u32)); - clk_cdiv &= CLK_SPI_CDIV_MASK; - clk_cdiv >>= CLK_SPI_CDIV_OFFSET; - dws->max_freq = MRST_SPI_CLK_BASE / (clk_cdiv + 1); - - iounmap(clk_reg); - - /* Register hook to configure CTRLR0 */ - dws->update_cr0 = dw_spi_update_cr0; - - dw_spi_mid_setup_dma_mfld(dws); - return 0; -} - -int dw_spi_mid_init_generic(struct dw_spi *dws) -{ - /* Register hook to configure CTRLR0 */ - dws->update_cr0 = dw_spi_update_cr0; - - dw_spi_mid_setup_dma_generic(dws); - return 0; -} diff --git a/drivers/spi/spi-dw-pci.c b/drivers/spi/spi-dw-pci.c index dde54a918b5d..c13707b8493e 100644 --- a/drivers/spi/spi-dw-pci.c +++ b/drivers/spi/spi-dw-pci.c @@ -15,6 +15,15 @@ #define DRIVER_NAME "dw_spi_pci" +/* HW info for MRST Clk Control Unit, 32b reg per controller */ +#define MRST_SPI_CLK_BASE 100000000 /* 100m */ +#define MRST_CLK_SPI_REG 0xff11d86c +#define CLK_SPI_BDIV_OFFSET 0 +#define CLK_SPI_BDIV_MASK 0x00000007 +#define CLK_SPI_CDIV_OFFSET 9 +#define CLK_SPI_CDIV_MASK 0x00000e00 +#define CLK_SPI_DISABLE_OFFSET 8 + struct spi_pci_desc { int (*setup)(struct dw_spi *); u16 num_cs; @@ -22,20 +31,55 @@ struct spi_pci_desc { u32 max_freq; }; +static int spi_mid_init(struct dw_spi *dws) +{ + void __iomem *clk_reg; + u32 clk_cdiv; + + clk_reg = ioremap(MRST_CLK_SPI_REG, 16); + if (!clk_reg) + return -ENOMEM; + + /* Get SPI controller operating freq info */ + clk_cdiv = readl(clk_reg + dws->bus_num * sizeof(u32)); + clk_cdiv &= CLK_SPI_CDIV_MASK; + clk_cdiv >>= CLK_SPI_CDIV_OFFSET; + dws->max_freq = MRST_SPI_CLK_BASE / (clk_cdiv + 1); + + iounmap(clk_reg); + + /* Register hook to configure CTRLR0 */ + dws->update_cr0 = dw_spi_update_cr0; + + dw_spi_mid_setup_dma_mfld(dws); + + return 0; +} + +static int spi_generic_init(struct dw_spi *dws) +{ + /* Register hook to configure CTRLR0 */ + dws->update_cr0 = dw_spi_update_cr0; + + dw_spi_mid_setup_dma_generic(dws); + + return 0; +} + static struct spi_pci_desc spi_pci_mid_desc_1 = { - .setup = dw_spi_mid_init_mfld, + .setup = spi_mid_init, .num_cs = 5, .bus_num = 0, }; static struct spi_pci_desc spi_pci_mid_desc_2 = { - .setup = dw_spi_mid_init_mfld, + .setup = spi_mid_init, .num_cs = 2, .bus_num = 1, }; static struct spi_pci_desc spi_pci_ehl_desc = { - .setup = dw_spi_mid_init_generic, + .setup = spi_generic_init, .num_cs = 2, .bus_num = -1, .max_freq = 100000000, diff --git a/drivers/spi/spi-dw.h b/drivers/spi/spi-dw.h index 9247670fcdfb..91608cf12636 100644 --- a/drivers/spi/spi-dw.h +++ b/drivers/spi/spi-dw.h @@ -257,8 +257,16 @@ extern u32 dw_spi_update_cr0_v1_01a(struct spi_controller *master, struct spi_device *spi, struct spi_transfer *transfer); -/* platform related setup */ -extern int dw_spi_mid_init_mfld(struct dw_spi *dws); -extern int dw_spi_mid_init_generic(struct dw_spi *dws); +#ifdef CONFIG_SPI_DW_DMA + +extern void dw_spi_mid_setup_dma_mfld(struct dw_spi *dws); +extern void dw_spi_mid_setup_dma_generic(struct dw_spi *dws); + +#else + +static inline void dw_spi_mid_setup_dma_mfld(struct dw_spi *dws) {} +static inline void dw_spi_mid_setup_dma_generic(struct dw_spi *dws) {} + +#endif /* !CONFIG_SPI_DW_DMA */ #endif /* DW_SPI_HEADER_H */ -- cgit v1.2.3