diff options
| -rw-r--r-- | drivers/spi/Makefile | 1 | ||||
| -rw-r--r-- | drivers/spi/xilinx_spi.c | 214 | ||||
| -rw-r--r-- | drivers/spi/xilinx_spi.h | 135 | 
3 files changed, 350 insertions, 0 deletions
| diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile index c967d8783..3ae38e590 100644 --- a/drivers/spi/Makefile +++ b/drivers/spi/Makefile @@ -44,6 +44,7 @@ COBJS-$(CONFIG_SOFT_SPI) += soft_spi.o  COBJS-$(CONFIG_SH_SPI) += sh_spi.o  COBJS-$(CONFIG_FSL_ESPI) += fsl_espi.o  COBJS-$(CONFIG_TEGRA2_SPI) += tegra2_spi.o +COBJS-$(CONFIG_XILINX_SPI) += xilinx_spi.o  COBJS	:= $(COBJS-y)  SRCS	:= $(COBJS:.o=.c) diff --git a/drivers/spi/xilinx_spi.c b/drivers/spi/xilinx_spi.c new file mode 100644 index 000000000..e563c1905 --- /dev/null +++ b/drivers/spi/xilinx_spi.c @@ -0,0 +1,214 @@ +/* + * Xilinx SPI driver + * + * supports 8 bit SPI transfers only, with or w/o FIFO + * + * based on bfin_spi.c, by way of altera_spi.c + * Copyright (c) 2005-2008 Analog Devices Inc. + * Copyright (c) 2010 Thomas Chou <thomas@wytron.com.tw> + * Copyright (c) 2010 Graeme Smecher <graeme.smecher@mail.mcgill.ca> + * Copyright (c) 2012 Stephan Linz <linz@li-pro.net> + * + * Licensed under the GPL-2 or later. + * + * [0]: http://www.xilinx.com/support/documentation + * + * [S]:	[0]/ip_documentation/xps_spi.pdf + *	[0]/ip_documentation/axi_spi_ds742.pdf + */ +#include <config.h> +#include <common.h> +#include <malloc.h> +#include <spi.h> + +#include "xilinx_spi.h" + +#ifndef CONFIG_SYS_XILINX_SPI_LIST +#define CONFIG_SYS_XILINX_SPI_LIST	{ CONFIG_SYS_SPI_BASE } +#endif + +#ifndef CONFIG_XILINX_SPI_IDLE_VAL +#define CONFIG_XILINX_SPI_IDLE_VAL	0xff +#endif + +#define XILSPI_SPICR_DFLT_ON		(SPICR_MANUAL_SS | \ +					 SPICR_MASTER_MODE | \ +					 SPICR_SPE) + +#define XILSPI_SPICR_DFLT_OFF		(SPICR_MASTER_INHIBIT | \ +					 SPICR_MANUAL_SS) + +#define XILSPI_MAX_XFER_BITS		8 + +static unsigned long xilinx_spi_base_list[] = CONFIG_SYS_XILINX_SPI_LIST; + +__attribute__((weak)) +int spi_cs_is_valid(unsigned int bus, unsigned int cs) +{ +	return bus < ARRAY_SIZE(xilinx_spi_base_list) && cs < 32; +} + +__attribute__((weak)) +void spi_cs_activate(struct spi_slave *slave) +{ +	struct xilinx_spi_slave *xilspi = to_xilinx_spi_slave(slave); + +	writel(SPISSR_ACT(slave->cs), &xilspi->regs->spissr); +} + +__attribute__((weak)) +void spi_cs_deactivate(struct spi_slave *slave) +{ +	struct xilinx_spi_slave *xilspi = to_xilinx_spi_slave(slave); + +	writel(SPISSR_OFF, &xilspi->regs->spissr); +} + +void spi_init(void) +{ +	/* do nothing */ +} + +void spi_set_speed(struct spi_slave *slave, uint hz) +{ +	/* xilinx spi core does not support programmable speed */ +} + +struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs, +				  unsigned int max_hz, unsigned int mode) +{ +	struct xilinx_spi_slave *xilspi; +	struct xilinx_spi_reg *regs; + +	if (!spi_cs_is_valid(bus, cs)) { +		printf("XILSPI error: %s: unsupported bus %d / cs %d\n", +				__func__, bus, cs); +		return NULL; +	} + +	xilspi = malloc(sizeof(*xilspi)); +	if (!xilspi) { +		printf("XILSPI error: %s: malloc of SPI structure failed\n", +				__func__); +		return NULL; +	} +	xilspi->slave.bus = bus; +	xilspi->slave.cs = cs; +	xilspi->regs = (struct xilinx_spi_reg *)xilinx_spi_base_list[bus]; +	xilspi->freq = max_hz; +	xilspi->mode = mode; +	debug("%s: bus:%i cs:%i base:%p mode:%x max_hz:%d\n", __func__, +		bus, cs, xilspi->regs, xilspi->mode, xilspi->freq); + +	return &xilspi->slave; +} + +void spi_free_slave(struct spi_slave *slave) +{ +	struct xilinx_spi_slave *xilspi = to_xilinx_spi_slave(slave); + +	free(xilspi); +} + +int spi_claim_bus(struct spi_slave *slave) +{ +	struct xilinx_spi_slave *xilspi = to_xilinx_spi_slave(slave); +	u32 spicr; + +	debug("%s: bus:%i cs:%i\n", __func__, slave->bus, slave->cs); +	writel(SPISSR_OFF, &xilspi->regs->spissr); + +	spicr = XILSPI_SPICR_DFLT_ON; +	if (xilspi->mode & SPI_LSB_FIRST) +		spicr |= SPICR_LSB_FIRST; +	if (xilspi->mode & SPI_CPHA) +		spicr |= SPICR_CPHA; +	if (xilspi->mode & SPI_CPOL) +		spicr |= SPICR_CPOL; +	if (xilspi->mode & SPI_LOOP) +		spicr |= SPICR_LOOP; + +	writel(spicr, &xilspi->regs->spicr); +	return 0; +} + +void spi_release_bus(struct spi_slave *slave) +{ +	struct xilinx_spi_slave *xilspi = to_xilinx_spi_slave(slave); + +	debug("%s: bus:%i cs:%i\n", __func__, slave->bus, slave->cs); +	writel(SPISSR_OFF, &xilspi->regs->spissr); +	writel(XILSPI_SPICR_DFLT_OFF, &xilspi->regs->spicr); +} + +int spi_xfer(struct spi_slave *slave, unsigned int bitlen, const void *dout, +	     void *din, unsigned long flags) +{ +	struct xilinx_spi_slave *xilspi = to_xilinx_spi_slave(slave); +	/* assume spi core configured to do 8 bit transfers */ +	unsigned int bytes = bitlen / XILSPI_MAX_XFER_BITS; +	const unsigned char *txp = dout; +	unsigned char *rxp = din; +	unsigned rxecount = 17;	/* max. 16 elements in FIFO, leftover 1 */ + +	debug("%s: bus:%i cs:%i bitlen:%i bytes:%i flags:%lx\n", __func__, +		slave->bus, slave->cs, bitlen, bytes, flags); +	if (bitlen == 0) +		goto done; + +	if (bitlen % XILSPI_MAX_XFER_BITS) { +		printf("XILSPI warning: %s: Not a multiple of %d bits\n", +				__func__, XILSPI_MAX_XFER_BITS); +		flags |= SPI_XFER_END; +		goto done; +	} + +	/* empty read buffer */ +	while (rxecount && !(readl(&xilspi->regs->spisr) & SPISR_RX_EMPTY)) { +		readl(&xilspi->regs->spidrr); +		rxecount--; +	} + +	if (!rxecount) { +		printf("XILSPI error: %s: Rx buffer not empty\n", __func__); +		return -1; +	} + +	if (flags & SPI_XFER_BEGIN) +		spi_cs_activate(slave); + +	while (bytes--) { +		unsigned timeout = /* at least 1usec or greater, leftover 1 */ +			xilspi->freq > XILSPI_MAX_XFER_BITS * 1000000 ? 2 : +			(XILSPI_MAX_XFER_BITS * 1000000 / xilspi->freq) + 1; + +		/* get Tx element from data out buffer and count up */ +		unsigned char d = txp ? *txp++ : CONFIG_XILINX_SPI_IDLE_VAL; +		debug("%s: tx:%x ", __func__, d); + +		/* write out and wait for processing (receive data) */ +		writel(d & SPIDTR_8BIT_MASK, &xilspi->regs->spidtr); +		while (timeout && readl(&xilspi->regs->spisr) +						& SPISR_RX_EMPTY) { +			timeout--; +			udelay(1); +		} + +		if (!timeout) { +			printf("XILSPI error: %s: Xfer timeout\n", __func__); +			return -1; +		} + +		/* read Rx element and push into data in buffer */ +		d = readl(&xilspi->regs->spidrr) & SPIDRR_8BIT_MASK; +		if (rxp) +			*rxp++ = d; +		debug("rx:%x\n", d); +	} + + done: +	if (flags & SPI_XFER_END) +		spi_cs_deactivate(slave); + +	return 0; +} diff --git a/drivers/spi/xilinx_spi.h b/drivers/spi/xilinx_spi.h new file mode 100644 index 000000000..32610d2a1 --- /dev/null +++ b/drivers/spi/xilinx_spi.h @@ -0,0 +1,135 @@ +/* + * Xilinx SPI driver + * + * XPS/AXI bus interface + * + * based on bfin_spi.c, by way of altera_spi.c + * Copyright (c) 2005-2008 Analog Devices Inc. + * Copyright (c) 2010 Thomas Chou <thomas@wytron.com.tw> + * Copyright (c) 2010 Graeme Smecher <graeme.smecher@mail.mcgill.ca> + * Copyright (c) 2012 Stephan Linz <linz@li-pro.net> + * + * Licensed under the GPL-2 or later. + * + * [0]: http://www.xilinx.com/support/documentation + * + * [S]:	[0]/ip_documentation/xps_spi.pdf + *	[0]/ip_documentation/axi_spi_ds742.pdf + */ +#ifndef _XILINX_SPI_ +#define _XILINX_SPI_ + +#include <asm/types.h> +#include <asm/io.h> + +/* + * Xilinx SPI Register Definition + * + * [1]:	[0]/ip_documentation/xps_spi.pdf + *	page 8, Register Descriptions + * [2]:	[0]/ip_documentation/axi_spi_ds742.pdf + *	page 7, Register Overview Table + */ +struct xilinx_spi_reg { +	u32 __space0__[7]; +	u32 dgier;	/* Device Global Interrupt Enable Register (DGIER) */ +	u32 ipisr;	/* IP Interrupt Status Register (IPISR) */ +	u32 __space1__; +	u32 ipier;	/* IP Interrupt Enable Register (IPIER) */ +	u32 __space2__[5]; +	u32 srr;	/* Softare Reset Register (SRR) */ +	u32 __space3__[7]; +	u32 spicr;	/* SPI Control Register (SPICR) */ +	u32 spisr;	/* SPI Status Register (SPISR) */ +	u32 spidtr;	/* SPI Data Transmit Register (SPIDTR) */ +	u32 spidrr;	/* SPI Data Receive Register (SPIDRR) */ +	u32 spissr;	/* SPI Slave Select Register (SPISSR) */ +	u32 spitfor;	/* SPI Transmit FIFO Occupancy Register (SPITFOR) */ +	u32 spirfor;	/* SPI Receive FIFO Occupancy Register (SPIRFOR) */ +}; + +/* Device Global Interrupt Enable Register (dgier), [1] p15, [2] p15 */ +#define DGIER_GIE		(1 << 31) + +/* IP Interrupt Status Register (ipisr), [1] p15, [2] p15 */ +#define IPISR_DRR_NOT_EMPTY	(1 << 8) +#define IPISR_SLAVE_SELECT	(1 << 7) +#define IPISR_TXF_HALF_EMPTY	(1 << 6) +#define IPISR_DRR_OVERRUN	(1 << 5) +#define IPISR_DRR_FULL		(1 << 4) +#define IPISR_DTR_UNDERRUN	(1 << 3) +#define IPISR_DTR_EMPTY		(1 << 2) +#define IPISR_SLAVE_MODF	(1 << 1) +#define IPISR_MODF		(1 << 0) + +/* IP Interrupt Enable Register (ipier), [1] p17, [2] p18 */ +#define IPIER_DRR_NOT_EMPTY	(1 << 8) +#define IPIER_SLAVE_SELECT	(1 << 7) +#define IPIER_TXF_HALF_EMPTY	(1 << 6) +#define IPIER_DRR_OVERRUN	(1 << 5) +#define IPIER_DRR_FULL		(1 << 4) +#define IPIER_DTR_UNDERRUN	(1 << 3) +#define IPIER_DTR_EMPTY		(1 << 2) +#define IPIER_SLAVE_MODF	(1 << 1) +#define IPIER_MODF		(1 << 0) + +/* Softare Reset Register (srr), [1] p9, [2] p8 */ +#define SRR_RESET_CODE		0x0000000A + +/* SPI Control Register (spicr), [1] p9, [2] p8 */ +#define SPICR_LSB_FIRST		(1 << 9) +#define SPICR_MASTER_INHIBIT	(1 << 8) +#define SPICR_MANUAL_SS		(1 << 7) +#define SPICR_RXFIFO_RESEST	(1 << 6) +#define SPICR_TXFIFO_RESEST	(1 << 5) +#define SPICR_CPHA		(1 << 4) +#define SPICR_CPOL		(1 << 3) +#define SPICR_MASTER_MODE	(1 << 2) +#define SPICR_SPE		(1 << 1) +#define SPICR_LOOP		(1 << 0) + +/* SPI Status Register (spisr), [1] p11, [2] p10 */ +#define SPISR_SLAVE_MODE_SELECT	(1 << 5) +#define SPISR_MODF		(1 << 4) +#define SPISR_TX_FULL		(1 << 3) +#define SPISR_TX_EMPTY		(1 << 2) +#define SPISR_RX_FULL		(1 << 1) +#define SPISR_RX_EMPTY		(1 << 0) + +/* SPI Data Transmit Register (spidtr), [1] p12, [2] p12 */ +#define SPIDTR_8BIT_MASK	(0xff << 0) +#define SPIDTR_16BIT_MASK	(0xffff << 0) +#define SPIDTR_32BIT_MASK	(0xffffffff << 0) + +/* SPI Data Receive Register (spidrr), [1] p12, [2] p12 */ +#define SPIDRR_8BIT_MASK	(0xff << 0) +#define SPIDRR_16BIT_MASK	(0xffff << 0) +#define SPIDRR_32BIT_MASK	(0xffffffff << 0) + +/* SPI Slave Select Register (spissr), [1] p13, [2] p13 */ +#define SPISSR_MASK(cs)		(1 << (cs)) +#define SPISSR_ACT(cs)		~SPISSR_MASK(cs) +#define SPISSR_OFF		~0UL + +/* SPI Transmit FIFO Occupancy Register (spitfor), [1] p13, [2] p14 */ +#define SPITFOR_OCYVAL_POS	0 +#define SPITFOR_OCYVAL_MASK	(0xf << SPITFOR_OCYVAL_POS) + +/* SPI Receive FIFO Occupancy Register (spirfor), [1] p14, [2] p14 */ +#define SPIRFOR_OCYVAL_POS	0 +#define SPIRFOR_OCYVAL_MASK	(0xf << SPIRFOR_OCYVAL_POS) + +struct xilinx_spi_slave { +	struct spi_slave slave; +	struct xilinx_spi_reg *regs; +	unsigned int freq; +	unsigned int mode; +}; + +static inline struct xilinx_spi_slave *to_xilinx_spi_slave( +					struct spi_slave *slave) +{ +	return container_of(slave, struct xilinx_spi_slave, slave); +} + +#endif /* _XILINX_SPI_ */ |