This code differs in only trivial ways from the altera_spi driver. It plays nice with Thomas Chou's mmc_spi driver, as well as with SPI flash.
Documentation for the SPI core is available here: http://www.xilinx.com/support/documentation/ip_documentation/xps_spi.pdf Signed-off-by: Graeme Smecher <graeme.smec...@mail.mcgill.ca> --- drivers/spi/Makefile | 1 + drivers/spi/xilinx_spi.c | 173 ++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 174 insertions(+), 0 deletions(-) create mode 100644 drivers/spi/xilinx_spi.c diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile index dfcbb8b..eeba5ef 100644 --- a/drivers/spi/Makefile +++ b/drivers/spi/Makefile @@ -36,6 +36,7 @@ COBJS-$(CONFIG_MPC52XX_SPI) += mpc52xx_spi.o COBJS-$(CONFIG_MPC8XXX_SPI) += mpc8xxx_spi.o COBJS-$(CONFIG_MXC_SPI) += mxc_spi.o COBJS-$(CONFIG_SOFT_SPI) += soft_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 0000000..281c369 --- /dev/null +++ b/drivers/spi/xilinx_spi.c @@ -0,0 +1,173 @@ +/* + * Xilinx SPI driver + * + * based on bfin_spi.c, by way of altera_spi.c + * Copyright (c) 2005-2008 Analog Devices Inc. + * Copyright (c) 2010 Thomas Chou <tho...@wytron.com.tw> + * Copyright (c) 2010 Graeme Smecher <graeme.smec...@mail.mcgill.ca> + * + * Licensed under the GPL-2 or later. + */ +#include <common.h> +#include <asm/io.h> +#include <malloc.h> +#include <spi.h> + +#define XILINX_SPI_RR 0x6c +#define XILINX_SPI_TR 0x68 +#define XILINX_SPI_SR 0x64 +#define XILINX_SPI_CR 0x60 +#define XILINX_SPI_SSR 0x70 + +#define XILINX_SPI_SR_RX_EMPTY_MSK 0x01 + +#define XILINX_SPI_CR_DEFAULT (0x0006) +#define XILINX_SPI_CR_MSS_MSK (0x0080) + +#if XPAR_XSPI_NUM_INSTANCES > 4 +# warning "The xilinx_spi driver will ignore some of your SPI peripherals!" +#endif + +static const ulong xilinx_spi_base_list[] = { +#ifdef XPAR_SPI_0_BASEADDR + XPAR_SPI_0_BASEADDR, +#endif +#ifdef XPAR_SPI_1_BASEADDR + XPAR_SPI_1_BASEADDR, +#endif +#ifdef XPAR_SPI_2_BASEADDR + XPAR_SPI_2_BASEADDR, +#endif +#ifdef XPAR_SPI_3_BASEADDR + XPAR_SPI_3_BASEADDR, +#endif +}; + +struct xilinx_spi_slave { + struct spi_slave slave; + ulong base; +}; +#define to_xilinx_spi_slave(s) container_of(s, struct xilinx_spi_slave, slave) + +__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(~(1 << slave->cs), xilspi->base + XILINX_SPI_SSR); + writel(XILINX_SPI_CR_DEFAULT | XILINX_SPI_CR_MSS_MSK, + xilspi->base + XILINX_SPI_CR); +} + +__attribute__((weak)) +void spi_cs_deactivate(struct spi_slave *slave) +{ + struct xilinx_spi_slave *xilspi = to_xilinx_spi_slave(slave); + + writel(XILINX_SPI_CR_DEFAULT, xilspi->base + XILINX_SPI_CR); + writel(~0, xilspi->base + XILINX_SPI_SSR); +} + +void spi_init(void) +{ +} + +struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs, + unsigned int max_hz, unsigned int mode) +{ + struct xilinx_spi_slave *xilspi; + + if (!spi_cs_is_valid(bus, cs)) + return NULL; + + xilspi = malloc(sizeof(*xilspi)); + if (!xilspi) + return NULL; + + xilspi->slave.bus = bus; + xilspi->slave.cs = cs; + xilspi->base = xilinx_spi_base_list[bus]; + debug("%s: bus:%i cs:%i base:%lx\n", __func__, + bus, cs, xilspi->base); + + 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); + + debug("%s: bus:%i cs:%i\n", __func__, slave->bus, slave->cs); + writel(XILINX_SPI_CR_DEFAULT, xilspi->base + XILINX_SPI_CR); + writel(~0, xilspi->base + XILINX_SPI_SSR); + 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(~0, xilspi->base + XILINX_SPI_SSR); +} + +#ifndef CONFIG_XILINX_SPI_IDLE_VAL +# define CONFIG_XILINX_SPI_IDLE_VAL 0xff +#endif + +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 */ + uint bytes = bitlen / 8; + const uchar *txp = dout; + uchar *rxp = din; + + 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 % 8) { + flags |= SPI_XFER_END; + goto done; + } + + /* empty read buffer */ + while (!(readl(xilspi->base + XILINX_SPI_SR) & + XILINX_SPI_SR_RX_EMPTY_MSK)) + readl(xilspi->base + XILINX_SPI_RR); + + if (flags & SPI_XFER_BEGIN) + spi_cs_activate(slave); + + while (bytes--) { + uchar d = txp ? *txp++ : CONFIG_XILINX_SPI_IDLE_VAL; + debug("%s: tx:%x ", __func__, d); + writel(d, xilspi->base + XILINX_SPI_TR); + while (readl(xilspi->base + XILINX_SPI_SR) & + XILINX_SPI_SR_RX_EMPTY_MSK) + ; + d = readl(xilspi->base + XILINX_SPI_RR); + if (rxp) + *rxp++ = d; + debug("rx:%x\n", d); + } + done: + if (flags & SPI_XFER_END) + spi_cs_deactivate(slave); + + return 0; +} -- 1.7.0.4 _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot
