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	spi: add support for microchip fpga spi controllers
Add a driver for Microchip FPGA SPI controllers, specifically supporting the "hard" controllers on PolarFire SoC. Co-developed-by: Daire McNamara <daire.mcnamara@microchip.com> Signed-off-by: Daire McNamara <daire.mcnamara@microchip.com> Signed-off-by: Conor Dooley <conor.dooley@microchip.com> Link: https://lore.kernel.org/r/20220607073833.2331539-2-conor.dooley@microchip.com Signed-off-by: Mark Brown <broonie@kernel.org>
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					 3 changed files with 642 additions and 0 deletions
				
			
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			@ -575,6 +575,15 @@ config SPI_MESON_SPIFC
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	  This enables master mode support for the SPIFC (SPI flash
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	  controller) available in Amlogic Meson SoCs.
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config SPI_MICROCHIP_CORE
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	tristate "Microchip FPGA SPI controllers"
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	depends on SPI_MASTER
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	help
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	  This enables the SPI driver for Microchip FPGA SPI controllers.
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	  Say Y or M here if you want to use the "hard" controllers on
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	  PolarFire SoC.
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	  If built as a module, it will be called spi-microchip-core.
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config SPI_MT65XX
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	tristate "MediaTek SPI controller"
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	depends on ARCH_MEDIATEK || COMPILE_TEST
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			@ -71,6 +71,7 @@ obj-$(CONFIG_SPI_LM70_LLP)		+= spi-lm70llp.o
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obj-$(CONFIG_SPI_LP8841_RTC)		+= spi-lp8841-rtc.o
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obj-$(CONFIG_SPI_MESON_SPICC)		+= spi-meson-spicc.o
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obj-$(CONFIG_SPI_MESON_SPIFC)		+= spi-meson-spifc.o
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obj-$(CONFIG_SPI_MICROCHIP_CORE)	+= spi-microchip-core.o
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obj-$(CONFIG_SPI_MPC512x_PSC)		+= spi-mpc512x-psc.o
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obj-$(CONFIG_SPI_MPC52xx_PSC)		+= spi-mpc52xx-psc.o
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obj-$(CONFIG_SPI_MPC52xx)		+= spi-mpc52xx.o
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										632
									
								
								drivers/spi/spi-microchip-core.c
									
									
									
									
									
										Normal file
									
								
							
							
						
						
									
										632
									
								
								drivers/spi/spi-microchip-core.c
									
									
									
									
									
										Normal file
									
								
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			@ -0,0 +1,632 @@
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// SPDX-License-Identifier: (GPL-2.0)
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/*
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 * Microchip CoreSPI SPI controller driver
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 *
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 * Copyright (c) 2018-2022 Microchip Technology Inc. and its subsidiaries
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 *
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 * Author: Daire McNamara <daire.mcnamara@microchip.com>
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 * Author: Conor Dooley <conor.dooley@microchip.com>
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 *
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 */
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#include <linux/clk.h>
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#include <linux/delay.h>
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#include <linux/err.h>
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#include <linux/init.h>
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#include <linux/interrupt.h>
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#include <linux/io.h>
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#include <linux/module.h>
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#include <linux/of.h>
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#include <linux/platform_device.h>
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#include <linux/spi/spi.h>
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#define MAX_LEN				(0xffff)
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#define MAX_CS				(8)
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#define DEFAULT_FRAMESIZE		(8)
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#define FIFO_DEPTH			(32)
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#define CLK_GEN_MODE1_MAX		(255)
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#define CLK_GEN_MODE0_MAX		(15)
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#define CLK_GEN_MIN			(0)
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#define MODE_X_MASK_SHIFT		(24)
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#define CONTROL_ENABLE			BIT(0)
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#define CONTROL_MASTER			BIT(1)
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#define CONTROL_RX_DATA_INT		BIT(4)
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#define CONTROL_TX_DATA_INT		BIT(5)
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#define CONTROL_RX_OVER_INT		BIT(6)
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#define CONTROL_TX_UNDER_INT		BIT(7)
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#define CONTROL_SPO			BIT(24)
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#define CONTROL_SPH			BIT(25)
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#define CONTROL_SPS			BIT(26)
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#define CONTROL_FRAMEURUN		BIT(27)
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#define CONTROL_CLKMODE			BIT(28)
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#define CONTROL_BIGFIFO			BIT(29)
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#define CONTROL_OENOFF			BIT(30)
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#define CONTROL_RESET			BIT(31)
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#define CONTROL_MODE_MASK		GENMASK(3, 2)
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#define  MOTOROLA_MODE			(0)
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#define CONTROL_FRAMECNT_MASK		GENMASK(23, 8)
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#define CONTROL_FRAMECNT_SHIFT		(8)
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#define STATUS_ACTIVE			BIT(14)
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#define STATUS_SSEL			BIT(13)
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#define STATUS_FRAMESTART		BIT(12)
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#define STATUS_TXFIFO_EMPTY_NEXT_READ	BIT(11)
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#define STATUS_TXFIFO_EMPTY		BIT(10)
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#define STATUS_TXFIFO_FULL_NEXT_WRITE	BIT(9)
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#define STATUS_TXFIFO_FULL		BIT(8)
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#define STATUS_RXFIFO_EMPTY_NEXT_READ	BIT(7)
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#define STATUS_RXFIFO_EMPTY		BIT(6)
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#define STATUS_RXFIFO_FULL_NEXT_WRITE	BIT(5)
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#define STATUS_RXFIFO_FULL		BIT(4)
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#define STATUS_TX_UNDERRUN		BIT(3)
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#define STATUS_RX_OVERFLOW		BIT(2)
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#define STATUS_RXDAT_RXED		BIT(1)
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#define STATUS_TXDAT_SENT		BIT(0)
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#define INT_TXDONE			BIT(0)
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#define INT_RXRDY			BIT(1)
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#define INT_RX_CHANNEL_OVERFLOW		BIT(2)
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#define INT_TX_CHANNEL_UNDERRUN		BIT(3)
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#define INT_ENABLE_MASK (CONTROL_RX_DATA_INT | CONTROL_TX_DATA_INT | \
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			 CONTROL_RX_OVER_INT | CONTROL_TX_UNDER_INT)
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#define REG_CONTROL		(0x00)
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#define REG_FRAME_SIZE		(0x04)
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#define REG_STATUS		(0x08)
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#define REG_INT_CLEAR		(0x0c)
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#define REG_RX_DATA		(0x10)
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#define REG_TX_DATA		(0x14)
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#define REG_CLK_GEN		(0x18)
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#define REG_SLAVE_SELECT	(0x1c)
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#define  SSEL_MASK		GENMASK(7, 0)
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#define  SSEL_DIRECT		BIT(8)
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#define  SSELOUT_SHIFT		9
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#define  SSELOUT		BIT(SSELOUT_SHIFT)
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#define REG_MIS			(0x20)
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#define REG_RIS			(0x24)
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#define REG_CONTROL2		(0x28)
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#define REG_COMMAND		(0x2c)
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#define REG_PKTSIZE		(0x30)
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#define REG_CMD_SIZE		(0x34)
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#define REG_HWSTATUS		(0x38)
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#define REG_STAT8		(0x3c)
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#define REG_CTRL2		(0x48)
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#define REG_FRAMESUP		(0x50)
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struct mchp_corespi {
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	void __iomem *regs;
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	struct clk *clk;
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	const u8 *tx_buf;
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	u8 *rx_buf;
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	u32 clk_gen; /* divider for spi output clock generated by the controller */
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	u32 clk_mode;
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	int irq;
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	int tx_len;
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	int rx_len;
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	int pending;
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};
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static inline u32 mchp_corespi_read(struct mchp_corespi *spi, unsigned int reg)
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{
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	return readl(spi->regs + reg);
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}
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static inline void mchp_corespi_write(struct mchp_corespi *spi, unsigned int reg, u32 val)
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{
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	writel(val, spi->regs + reg);
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}
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static inline void mchp_corespi_enable(struct mchp_corespi *spi)
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{
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	u32 control = mchp_corespi_read(spi, REG_CONTROL);
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	control |= CONTROL_ENABLE;
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	mchp_corespi_write(spi, REG_CONTROL, control);
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}
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static inline void mchp_corespi_disable(struct mchp_corespi *spi)
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{
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	u32 control = mchp_corespi_read(spi, REG_CONTROL);
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	control &= ~CONTROL_ENABLE;
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	mchp_corespi_write(spi, REG_CONTROL, control);
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}
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static inline void mchp_corespi_read_fifo(struct mchp_corespi *spi)
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{
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	u8 data;
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	int fifo_max, i = 0;
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	fifo_max = min(spi->rx_len, FIFO_DEPTH);
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	while ((i < fifo_max) && !(mchp_corespi_read(spi, REG_STATUS) & STATUS_RXFIFO_EMPTY)) {
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		data = mchp_corespi_read(spi, REG_RX_DATA);
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		if (spi->rx_buf)
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			*spi->rx_buf++ = data;
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		i++;
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	}
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	spi->rx_len -= i;
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	spi->pending -= i;
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}
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static void mchp_corespi_enable_ints(struct mchp_corespi *spi)
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{
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	u32 control, mask = INT_ENABLE_MASK;
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	mchp_corespi_disable(spi);
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	control = mchp_corespi_read(spi, REG_CONTROL);
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	control |= mask;
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	mchp_corespi_write(spi, REG_CONTROL, control);
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	control |= CONTROL_ENABLE;
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	mchp_corespi_write(spi, REG_CONTROL, control);
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}
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static void mchp_corespi_disable_ints(struct mchp_corespi *spi)
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{
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	u32 control, mask = INT_ENABLE_MASK;
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	mchp_corespi_disable(spi);
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	control = mchp_corespi_read(spi, REG_CONTROL);
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	control &= ~mask;
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	mchp_corespi_write(spi, REG_CONTROL, control);
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	control |= CONTROL_ENABLE;
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	mchp_corespi_write(spi, REG_CONTROL, control);
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}
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static inline void mchp_corespi_set_xfer_size(struct mchp_corespi *spi, int len)
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{
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	u32 control;
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	u16 lenpart;
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	/*
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	 * Disable the SPI controller. Writes to transfer length have
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	 * no effect when the controller is enabled.
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	 */
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	mchp_corespi_disable(spi);
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	/*
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	 * The lower 16 bits of the frame count are stored in the control reg
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	 * for legacy reasons, but the upper 16 written to a different register:
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	 * FRAMESUP. While both the upper and lower bits can be *READ* from the
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	 * FRAMESUP register, writing to the lower 16 bits is a NOP
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	 */
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	lenpart = len & 0xffff;
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	control = mchp_corespi_read(spi, REG_CONTROL);
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	control &= ~CONTROL_FRAMECNT_MASK;
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	control |= lenpart << CONTROL_FRAMECNT_SHIFT;
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	mchp_corespi_write(spi, REG_CONTROL, control);
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	lenpart = len & 0xffff0000;
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	mchp_corespi_write(spi, REG_FRAMESUP, lenpart);
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	control |= CONTROL_ENABLE;
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	mchp_corespi_write(spi, REG_CONTROL, control);
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}
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static inline void mchp_corespi_write_fifo(struct mchp_corespi *spi)
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{
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	u8 byte;
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	int fifo_max, i = 0;
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	fifo_max = min(spi->tx_len, FIFO_DEPTH);
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	mchp_corespi_set_xfer_size(spi, fifo_max);
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	while ((i < fifo_max) && !(mchp_corespi_read(spi, REG_STATUS) & STATUS_TXFIFO_FULL)) {
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		byte = spi->tx_buf ? *spi->tx_buf++ : 0xaa;
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		mchp_corespi_write(spi, REG_TX_DATA, byte);
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		i++;
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	}
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	spi->tx_len -= i;
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	spi->pending += i;
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}
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static inline void mchp_corespi_set_framesize(struct mchp_corespi *spi, int bt)
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{
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	u32 control;
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	/*
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	 * Disable the SPI controller. Writes to the frame size have
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	 * no effect when the controller is enabled.
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	 */
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	mchp_corespi_disable(spi);
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	mchp_corespi_write(spi, REG_FRAME_SIZE, bt);
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	control = mchp_corespi_read(spi, REG_CONTROL);
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	control |= CONTROL_ENABLE;
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	mchp_corespi_write(spi, REG_CONTROL, control);
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}
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static void mchp_corespi_set_cs(struct spi_device *spi, bool disable)
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{
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	u32 reg;
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	struct mchp_corespi *corespi = spi_master_get_devdata(spi->master);
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	reg = mchp_corespi_read(corespi, REG_SLAVE_SELECT);
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	reg &= ~BIT(spi->chip_select);
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	reg |= !disable << spi->chip_select;
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	mchp_corespi_write(corespi, REG_SLAVE_SELECT, reg);
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}
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static int mchp_corespi_setup(struct spi_device *spi)
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{
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	struct mchp_corespi *corespi = spi_master_get_devdata(spi->master);
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	u32 reg;
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	/*
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	 * Active high slaves need to be specifically set to their inactive
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	 * states during probe by adding them to the "control group" & thus
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	 * driving their select line low.
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	 */
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	if (spi->mode & SPI_CS_HIGH) {
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		reg = mchp_corespi_read(corespi, REG_SLAVE_SELECT);
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		reg |= BIT(spi->chip_select);
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		mchp_corespi_write(corespi, REG_SLAVE_SELECT, reg);
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	}
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	return 0;
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}
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static void mchp_corespi_init(struct spi_master *master, struct mchp_corespi *spi)
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{
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	unsigned long clk_hz;
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	u32 control = mchp_corespi_read(spi, REG_CONTROL);
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	control |= CONTROL_MASTER;
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	control &= ~CONTROL_MODE_MASK;
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	control |= MOTOROLA_MODE;
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	mchp_corespi_set_framesize(spi, DEFAULT_FRAMESIZE);
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	/* max. possible spi clock rate is the apb clock rate */
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	clk_hz = clk_get_rate(spi->clk);
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	master->max_speed_hz = clk_hz;
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	/*
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	 * The controller must be configured so that it doesn't remove Chip
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	 * Select until the entire message has been transferred, even if at
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	 * some points TX FIFO becomes empty.
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	 *
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	 * BIGFIFO mode is also enabled, which sets the fifo depth to 32 frames
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	 * for the 8 bit transfers that this driver uses.
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	 */
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	control = mchp_corespi_read(spi, REG_CONTROL);
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	control |= CONTROL_SPS | CONTROL_BIGFIFO;
 | 
			
		||||
 | 
			
		||||
	mchp_corespi_write(spi, REG_CONTROL, control);
 | 
			
		||||
 | 
			
		||||
	mchp_corespi_enable_ints(spi);
 | 
			
		||||
 | 
			
		||||
	/*
 | 
			
		||||
	 * It is required to enable direct mode, otherwise control over the chip
 | 
			
		||||
	 * select is relinquished to the hardware. SSELOUT is enabled too so we
 | 
			
		||||
	 * can deal with active high slaves.
 | 
			
		||||
	 */
 | 
			
		||||
	mchp_corespi_write(spi, REG_SLAVE_SELECT, SSELOUT | SSEL_DIRECT);
 | 
			
		||||
 | 
			
		||||
	control = mchp_corespi_read(spi, REG_CONTROL);
 | 
			
		||||
 | 
			
		||||
	control &= ~CONTROL_RESET;
 | 
			
		||||
	control |= CONTROL_ENABLE;
 | 
			
		||||
 | 
			
		||||
	mchp_corespi_write(spi, REG_CONTROL, control);
 | 
			
		||||
}
 | 
			
		||||
 | 
			
		||||
static inline void mchp_corespi_set_clk_gen(struct mchp_corespi *spi)
 | 
			
		||||
{
 | 
			
		||||
	u32 control;
 | 
			
		||||
 | 
			
		||||
	mchp_corespi_disable(spi);
 | 
			
		||||
 | 
			
		||||
	control = mchp_corespi_read(spi, REG_CONTROL);
 | 
			
		||||
	if (spi->clk_mode)
 | 
			
		||||
		control |= CONTROL_CLKMODE;
 | 
			
		||||
	else
 | 
			
		||||
		control &= ~CONTROL_CLKMODE;
 | 
			
		||||
 | 
			
		||||
	mchp_corespi_write(spi, REG_CLK_GEN, spi->clk_gen);
 | 
			
		||||
	mchp_corespi_write(spi, REG_CONTROL, control);
 | 
			
		||||
	mchp_corespi_write(spi, REG_CONTROL, control | CONTROL_ENABLE);
 | 
			
		||||
}
 | 
			
		||||
 | 
			
		||||
static inline void mchp_corespi_set_mode(struct mchp_corespi *spi, unsigned int mode)
 | 
			
		||||
{
 | 
			
		||||
	u32 control, mode_val;
 | 
			
		||||
 | 
			
		||||
	switch (mode & SPI_MODE_X_MASK) {
 | 
			
		||||
	case SPI_MODE_0:
 | 
			
		||||
		mode_val = 0;
 | 
			
		||||
		break;
 | 
			
		||||
	case SPI_MODE_1:
 | 
			
		||||
		mode_val = CONTROL_SPH;
 | 
			
		||||
		break;
 | 
			
		||||
	case SPI_MODE_2:
 | 
			
		||||
		mode_val = CONTROL_SPO;
 | 
			
		||||
		break;
 | 
			
		||||
	case SPI_MODE_3:
 | 
			
		||||
		mode_val = CONTROL_SPH | CONTROL_SPO;
 | 
			
		||||
		break;
 | 
			
		||||
	}
 | 
			
		||||
 | 
			
		||||
	/*
 | 
			
		||||
	 * Disable the SPI controller. Writes to the frame size have
 | 
			
		||||
	 * no effect when the controller is enabled.
 | 
			
		||||
	 */
 | 
			
		||||
	mchp_corespi_disable(spi);
 | 
			
		||||
 | 
			
		||||
	control = mchp_corespi_read(spi, REG_CONTROL);
 | 
			
		||||
	control &= ~(SPI_MODE_X_MASK << MODE_X_MASK_SHIFT);
 | 
			
		||||
	control |= mode_val;
 | 
			
		||||
 | 
			
		||||
	mchp_corespi_write(spi, REG_CONTROL, control);
 | 
			
		||||
 | 
			
		||||
	control |= CONTROL_ENABLE;
 | 
			
		||||
	mchp_corespi_write(spi, REG_CONTROL, control);
 | 
			
		||||
}
 | 
			
		||||
 | 
			
		||||
static irqreturn_t mchp_corespi_interrupt(int irq, void *dev_id)
 | 
			
		||||
{
 | 
			
		||||
	struct spi_master *master = dev_id;
 | 
			
		||||
	struct mchp_corespi *spi = spi_master_get_devdata(master);
 | 
			
		||||
	u32 intfield = mchp_corespi_read(spi, REG_MIS) & 0xf;
 | 
			
		||||
	bool finalise = false;
 | 
			
		||||
 | 
			
		||||
	/* Interrupt line may be shared and not for us at all */
 | 
			
		||||
	if (intfield == 0)
 | 
			
		||||
		return IRQ_NONE;
 | 
			
		||||
 | 
			
		||||
	if (intfield & INT_TXDONE) {
 | 
			
		||||
		mchp_corespi_write(spi, REG_INT_CLEAR, INT_TXDONE);
 | 
			
		||||
 | 
			
		||||
		if (spi->rx_len)
 | 
			
		||||
			mchp_corespi_read_fifo(spi);
 | 
			
		||||
 | 
			
		||||
		if (spi->tx_len)
 | 
			
		||||
			mchp_corespi_write_fifo(spi);
 | 
			
		||||
 | 
			
		||||
		if (!spi->rx_len)
 | 
			
		||||
			finalise = true;
 | 
			
		||||
	}
 | 
			
		||||
 | 
			
		||||
	if (intfield & INT_RXRDY)
 | 
			
		||||
		mchp_corespi_write(spi, REG_INT_CLEAR, INT_RXRDY);
 | 
			
		||||
 | 
			
		||||
	if (intfield & INT_RX_CHANNEL_OVERFLOW) {
 | 
			
		||||
		mchp_corespi_write(spi, REG_INT_CLEAR, INT_RX_CHANNEL_OVERFLOW);
 | 
			
		||||
		finalise = true;
 | 
			
		||||
		dev_err(&master->dev,
 | 
			
		||||
			"%s: RX OVERFLOW: rxlen: %d, txlen: %d\n", __func__,
 | 
			
		||||
			spi->rx_len, spi->tx_len);
 | 
			
		||||
	}
 | 
			
		||||
 | 
			
		||||
	if (intfield & INT_TX_CHANNEL_UNDERRUN) {
 | 
			
		||||
		mchp_corespi_write(spi, REG_INT_CLEAR, INT_TX_CHANNEL_UNDERRUN);
 | 
			
		||||
		finalise = true;
 | 
			
		||||
		dev_err(&master->dev,
 | 
			
		||||
			"%s: TX UNDERFLOW: rxlen: %d, txlen: %d\n", __func__,
 | 
			
		||||
			spi->rx_len, spi->tx_len);
 | 
			
		||||
	}
 | 
			
		||||
 | 
			
		||||
	if (finalise)
 | 
			
		||||
		spi_finalize_current_transfer(master);
 | 
			
		||||
 | 
			
		||||
	return IRQ_HANDLED;
 | 
			
		||||
}
 | 
			
		||||
 | 
			
		||||
static int mchp_corespi_calculate_clkgen(struct mchp_corespi *spi,
 | 
			
		||||
					 unsigned long target_hz)
 | 
			
		||||
{
 | 
			
		||||
	unsigned long clk_hz, spi_hz, clk_gen;
 | 
			
		||||
 | 
			
		||||
	clk_hz = clk_get_rate(spi->clk);
 | 
			
		||||
	spi_hz = min(target_hz, clk_hz);
 | 
			
		||||
 | 
			
		||||
	/*
 | 
			
		||||
	 * There are two possible clock modes for the controller generated
 | 
			
		||||
	 * clock's division ratio:
 | 
			
		||||
	 * CLK_MODE = 0: 1 / (2^(CLK_GEN + 1)) where CLK_GEN = 0 to 15.
 | 
			
		||||
	 * CLK_MODE = 1: 1 / (2 * CLK_GEN + 1) where CLK_GEN = 0 to 255.
 | 
			
		||||
	 * First try mode 1, fall back to 0 and if we have tried both modes and
 | 
			
		||||
	 * we /still/ can't get a good setting, we then throw the toys out of
 | 
			
		||||
	 * the pram and give up
 | 
			
		||||
	 * clk_gen is the register name for the clock divider on MPFS.
 | 
			
		||||
	 */
 | 
			
		||||
	clk_gen = DIV_ROUND_UP(clk_hz, 2 * spi_hz) - 1;
 | 
			
		||||
	if (clk_gen > CLK_GEN_MODE1_MAX || clk_gen <= CLK_GEN_MIN) {
 | 
			
		||||
		clk_gen = DIV_ROUND_UP(clk_hz, spi_hz);
 | 
			
		||||
		clk_gen = fls(clk_gen) - 1;
 | 
			
		||||
 | 
			
		||||
		if (clk_gen > CLK_GEN_MODE0_MAX)
 | 
			
		||||
			return -EINVAL;
 | 
			
		||||
 | 
			
		||||
		spi->clk_mode = 0;
 | 
			
		||||
	} else {
 | 
			
		||||
		spi->clk_mode = 1;
 | 
			
		||||
	}
 | 
			
		||||
 | 
			
		||||
	spi->clk_gen = clk_gen;
 | 
			
		||||
	return 0;
 | 
			
		||||
}
 | 
			
		||||
 | 
			
		||||
static int mchp_corespi_transfer_one(struct spi_master *master,
 | 
			
		||||
				     struct spi_device *spi_dev,
 | 
			
		||||
				     struct spi_transfer *xfer)
 | 
			
		||||
{
 | 
			
		||||
	struct mchp_corespi *spi = spi_master_get_devdata(master);
 | 
			
		||||
	int ret;
 | 
			
		||||
 | 
			
		||||
	ret = mchp_corespi_calculate_clkgen(spi, (unsigned long)xfer->speed_hz);
 | 
			
		||||
	if (ret) {
 | 
			
		||||
		dev_err(&master->dev, "failed to set clk_gen for target %u Hz\n", xfer->speed_hz);
 | 
			
		||||
		return ret;
 | 
			
		||||
	}
 | 
			
		||||
 | 
			
		||||
	mchp_corespi_set_clk_gen(spi);
 | 
			
		||||
 | 
			
		||||
	spi->tx_buf = xfer->tx_buf;
 | 
			
		||||
	spi->rx_buf = xfer->rx_buf;
 | 
			
		||||
	spi->tx_len = xfer->len;
 | 
			
		||||
	spi->rx_len = xfer->len;
 | 
			
		||||
	spi->pending = 0;
 | 
			
		||||
 | 
			
		||||
	mchp_corespi_set_xfer_size(spi, (spi->tx_len > FIFO_DEPTH)
 | 
			
		||||
				   ? FIFO_DEPTH : spi->tx_len);
 | 
			
		||||
 | 
			
		||||
	if (spi->tx_len)
 | 
			
		||||
		mchp_corespi_write_fifo(spi);
 | 
			
		||||
	return 1;
 | 
			
		||||
}
 | 
			
		||||
 | 
			
		||||
static int mchp_corespi_prepare_message(struct spi_master *master,
 | 
			
		||||
					struct spi_message *msg)
 | 
			
		||||
{
 | 
			
		||||
	struct spi_device *spi_dev = msg->spi;
 | 
			
		||||
	struct mchp_corespi *spi = spi_master_get_devdata(master);
 | 
			
		||||
 | 
			
		||||
	mchp_corespi_set_framesize(spi, DEFAULT_FRAMESIZE);
 | 
			
		||||
	mchp_corespi_set_mode(spi, spi_dev->mode);
 | 
			
		||||
 | 
			
		||||
	return 0;
 | 
			
		||||
}
 | 
			
		||||
 | 
			
		||||
static int mchp_corespi_probe(struct platform_device *pdev)
 | 
			
		||||
{
 | 
			
		||||
	struct spi_master *master;
 | 
			
		||||
	struct mchp_corespi *spi;
 | 
			
		||||
	struct resource *res;
 | 
			
		||||
	u32 num_cs;
 | 
			
		||||
	int ret = 0;
 | 
			
		||||
 | 
			
		||||
	master = spi_alloc_master(&pdev->dev, sizeof(*spi));
 | 
			
		||||
	if (!master)
 | 
			
		||||
		return dev_err_probe(&pdev->dev, -ENOMEM,
 | 
			
		||||
				     "unable to allocate master for SPI controller\n");
 | 
			
		||||
 | 
			
		||||
	platform_set_drvdata(pdev, master);
 | 
			
		||||
 | 
			
		||||
	if (of_property_read_u32(pdev->dev.of_node, "num-cs", &num_cs))
 | 
			
		||||
		num_cs = MAX_CS;
 | 
			
		||||
 | 
			
		||||
	master->num_chipselect = num_cs;
 | 
			
		||||
	master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
 | 
			
		||||
	master->setup = mchp_corespi_setup;
 | 
			
		||||
	master->bits_per_word_mask = SPI_BPW_MASK(8);
 | 
			
		||||
	master->transfer_one = mchp_corespi_transfer_one;
 | 
			
		||||
	master->prepare_message = mchp_corespi_prepare_message;
 | 
			
		||||
	master->set_cs = mchp_corespi_set_cs;
 | 
			
		||||
	master->dev.of_node = pdev->dev.of_node;
 | 
			
		||||
 | 
			
		||||
	spi = spi_master_get_devdata(master);
 | 
			
		||||
 | 
			
		||||
	spi->regs = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
 | 
			
		||||
	if (IS_ERR(spi->regs)) {
 | 
			
		||||
		ret = PTR_ERR(spi->regs);
 | 
			
		||||
		goto error_release_master;
 | 
			
		||||
	}
 | 
			
		||||
 | 
			
		||||
	spi->irq = platform_get_irq(pdev, 0);
 | 
			
		||||
	if (spi->irq <= 0) {
 | 
			
		||||
		dev_err(&pdev->dev, "invalid IRQ %d for SPI controller\n", spi->irq);
 | 
			
		||||
		ret = spi->irq;
 | 
			
		||||
		goto error_release_master;
 | 
			
		||||
	}
 | 
			
		||||
 | 
			
		||||
	ret = devm_request_irq(&pdev->dev, spi->irq, mchp_corespi_interrupt,
 | 
			
		||||
			       IRQF_SHARED, dev_name(&pdev->dev), master);
 | 
			
		||||
	if (ret) {
 | 
			
		||||
		dev_err(&pdev->dev, "could not request irq: %d\n", ret);
 | 
			
		||||
		goto error_release_master;
 | 
			
		||||
	}
 | 
			
		||||
 | 
			
		||||
	spi->clk = devm_clk_get(&pdev->dev, NULL);
 | 
			
		||||
	if (!spi->clk || IS_ERR(spi->clk)) {
 | 
			
		||||
		ret = PTR_ERR(spi->clk);
 | 
			
		||||
		dev_err(&pdev->dev, "could not get clk: %d\n", ret);
 | 
			
		||||
		goto error_release_master;
 | 
			
		||||
	}
 | 
			
		||||
 | 
			
		||||
	ret = clk_prepare_enable(spi->clk);
 | 
			
		||||
	if (ret) {
 | 
			
		||||
		dev_err(&pdev->dev, "failed to enable clock\n");
 | 
			
		||||
		goto error_release_master;
 | 
			
		||||
	}
 | 
			
		||||
 | 
			
		||||
	mchp_corespi_init(master, spi);
 | 
			
		||||
 | 
			
		||||
	ret = devm_spi_register_master(&pdev->dev, master);
 | 
			
		||||
	if (ret) {
 | 
			
		||||
		dev_err(&pdev->dev,
 | 
			
		||||
			"unable to register master for SPI controller\n");
 | 
			
		||||
		goto error_release_hardware;
 | 
			
		||||
	}
 | 
			
		||||
 | 
			
		||||
	dev_info(&pdev->dev, "Registered SPI controller %d\n", master->bus_num);
 | 
			
		||||
 | 
			
		||||
	return 0;
 | 
			
		||||
 | 
			
		||||
error_release_hardware:
 | 
			
		||||
	mchp_corespi_disable(spi);
 | 
			
		||||
	clk_prepare_enable(spi->clk);
 | 
			
		||||
error_release_master:
 | 
			
		||||
	spi_master_put(master);
 | 
			
		||||
 | 
			
		||||
	return ret;
 | 
			
		||||
}
 | 
			
		||||
 | 
			
		||||
static int mchp_corespi_remove(struct platform_device *pdev)
 | 
			
		||||
{
 | 
			
		||||
	struct spi_master *master  = platform_get_drvdata(pdev);
 | 
			
		||||
	struct mchp_corespi *spi = spi_master_get_devdata(master);
 | 
			
		||||
 | 
			
		||||
	mchp_corespi_disable_ints(spi);
 | 
			
		||||
	spi_unregister_master(master);
 | 
			
		||||
	spi_master_put(master);
 | 
			
		||||
	clk_disable_unprepare(spi->clk);
 | 
			
		||||
	mchp_corespi_disable(spi);
 | 
			
		||||
 | 
			
		||||
	return 0;
 | 
			
		||||
}
 | 
			
		||||
 | 
			
		||||
#define MICROCHIP_SPI_PM_OPS (NULL)
 | 
			
		||||
 | 
			
		||||
/*
 | 
			
		||||
 * Platform driver data structure
 | 
			
		||||
 */
 | 
			
		||||
 | 
			
		||||
#if defined(CONFIG_OF)
 | 
			
		||||
static const struct of_device_id mchp_corespi_dt_ids[] = {
 | 
			
		||||
	{ .compatible = "microchip,mpfs-spi" },
 | 
			
		||||
	{ /* sentinel */ }
 | 
			
		||||
};
 | 
			
		||||
MODULE_DEVICE_TABLE(of, mchp_corespi_dt_ids);
 | 
			
		||||
#endif
 | 
			
		||||
 | 
			
		||||
static struct platform_driver mchp_corespi_driver = {
 | 
			
		||||
	.probe = mchp_corespi_probe,
 | 
			
		||||
	.driver = {
 | 
			
		||||
		.name = "microchip-corespi",
 | 
			
		||||
		.pm = MICROCHIP_SPI_PM_OPS,
 | 
			
		||||
		.of_match_table = of_match_ptr(mchp_corespi_dt_ids),
 | 
			
		||||
		.owner = THIS_MODULE,
 | 
			
		||||
	},
 | 
			
		||||
	.remove = mchp_corespi_remove,
 | 
			
		||||
};
 | 
			
		||||
module_platform_driver(mchp_corespi_driver);
 | 
			
		||||
MODULE_DESCRIPTION("Microchip coreSPI SPI controller driver");
 | 
			
		||||
MODULE_AUTHOR("Daire McNamara <daire.mcnamara@microchip.com>");
 | 
			
		||||
MODULE_AUTHOR("Conor Dooley <conor.dooley@microchip.com>");
 | 
			
		||||
MODULE_LICENSE("GPL");
 | 
			
		||||
		Loading…
	
		Reference in a new issue