1 /* 2 * Altera SPI driver 3 * 4 * based on bfin_spi.c 5 * Copyright (c) 2005-2008 Analog Devices Inc. 6 * Copyright (C) 2010 Thomas Chou <thomas@wytron.com.tw> 7 * 8 * SPDX-License-Identifier: GPL-2.0+ 9 */ 10 #include <common.h> 11 #include <asm/io.h> 12 #include <malloc.h> 13 #include <spi.h> 14 15 struct altera_spi_regs { 16 u32 rxdata; 17 u32 txdata; 18 u32 status; 19 u32 control; 20 u32 _reserved; 21 u32 slave_sel; 22 }; 23 24 #define ALTERA_SPI_STATUS_ROE_MSK (1 << 3) 25 #define ALTERA_SPI_STATUS_TOE_MSK (1 << 4) 26 #define ALTERA_SPI_STATUS_TMT_MSK (1 << 5) 27 #define ALTERA_SPI_STATUS_TRDY_MSK (1 << 6) 28 #define ALTERA_SPI_STATUS_RRDY_MSK (1 << 7) 29 #define ALTERA_SPI_STATUS_E_MSK (1 << 8) 30 31 #define ALTERA_SPI_CONTROL_IROE_MSK (1 << 3) 32 #define ALTERA_SPI_CONTROL_ITOE_MSK (1 << 4) 33 #define ALTERA_SPI_CONTROL_ITRDY_MSK (1 << 6) 34 #define ALTERA_SPI_CONTROL_IRRDY_MSK (1 << 7) 35 #define ALTERA_SPI_CONTROL_IE_MSK (1 << 8) 36 #define ALTERA_SPI_CONTROL_SSO_MSK (1 << 10) 37 38 #ifndef CONFIG_SYS_ALTERA_SPI_LIST 39 #define CONFIG_SYS_ALTERA_SPI_LIST { CONFIG_SYS_SPI_BASE } 40 #endif 41 42 static ulong altera_spi_base_list[] = CONFIG_SYS_ALTERA_SPI_LIST; 43 44 struct altera_spi_slave { 45 struct spi_slave slave; 46 struct altera_spi_regs *regs; 47 }; 48 #define to_altera_spi_slave(s) container_of(s, struct altera_spi_slave, slave) 49 50 __attribute__((weak)) 51 int spi_cs_is_valid(unsigned int bus, unsigned int cs) 52 { 53 return bus < ARRAY_SIZE(altera_spi_base_list) && cs < 32; 54 } 55 56 __attribute__((weak)) 57 void spi_cs_activate(struct spi_slave *slave) 58 { 59 struct altera_spi_slave *altspi = to_altera_spi_slave(slave); 60 writel(1 << slave->cs, &altspi->regs->slave_sel); 61 writel(ALTERA_SPI_CONTROL_SSO_MSK, &altspi->regs->control); 62 } 63 64 __attribute__((weak)) 65 void spi_cs_deactivate(struct spi_slave *slave) 66 { 67 struct altera_spi_slave *altspi = to_altera_spi_slave(slave); 68 writel(0, &altspi->regs->control); 69 writel(0, &altspi->regs->slave_sel); 70 } 71 72 void spi_init(void) 73 { 74 } 75 76 void spi_set_speed(struct spi_slave *slave, uint hz) 77 { 78 /* altera spi core does not support programmable speed */ 79 } 80 81 struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs, 82 unsigned int max_hz, unsigned int mode) 83 { 84 struct altera_spi_slave *altspi; 85 86 if (!spi_cs_is_valid(bus, cs)) 87 return NULL; 88 89 altspi = spi_alloc_slave(struct altera_spi_slave, bus, cs); 90 if (!altspi) 91 return NULL; 92 93 altspi->regs = (struct altera_spi_regs *)altera_spi_base_list[bus]; 94 debug("%s: bus:%i cs:%i base:%p\n", __func__, 95 bus, cs, altspi->regs); 96 97 return &altspi->slave; 98 } 99 100 void spi_free_slave(struct spi_slave *slave) 101 { 102 struct altera_spi_slave *altspi = to_altera_spi_slave(slave); 103 free(altspi); 104 } 105 106 int spi_claim_bus(struct spi_slave *slave) 107 { 108 struct altera_spi_slave *altspi = to_altera_spi_slave(slave); 109 110 debug("%s: bus:%i cs:%i\n", __func__, slave->bus, slave->cs); 111 writel(0, &altspi->regs->control); 112 writel(0, &altspi->regs->slave_sel); 113 return 0; 114 } 115 116 void spi_release_bus(struct spi_slave *slave) 117 { 118 struct altera_spi_slave *altspi = to_altera_spi_slave(slave); 119 120 debug("%s: bus:%i cs:%i\n", __func__, slave->bus, slave->cs); 121 writel(0, &altspi->regs->slave_sel); 122 } 123 124 #ifndef CONFIG_ALTERA_SPI_IDLE_VAL 125 # define CONFIG_ALTERA_SPI_IDLE_VAL 0xff 126 #endif 127 128 int spi_xfer(struct spi_slave *slave, unsigned int bitlen, const void *dout, 129 void *din, unsigned long flags) 130 { 131 struct altera_spi_slave *altspi = to_altera_spi_slave(slave); 132 /* assume spi core configured to do 8 bit transfers */ 133 uint bytes = bitlen / 8; 134 const uchar *txp = dout; 135 uchar *rxp = din; 136 137 debug("%s: bus:%i cs:%i bitlen:%i bytes:%i flags:%lx\n", __func__, 138 slave->bus, slave->cs, bitlen, bytes, flags); 139 if (bitlen == 0) 140 goto done; 141 142 if (bitlen % 8) { 143 flags |= SPI_XFER_END; 144 goto done; 145 } 146 147 /* empty read buffer */ 148 if (readl(&altspi->regs->status) & ALTERA_SPI_STATUS_RRDY_MSK) 149 readl(&altspi->regs->rxdata); 150 if (flags & SPI_XFER_BEGIN) 151 spi_cs_activate(slave); 152 153 while (bytes--) { 154 uchar d = txp ? *txp++ : CONFIG_ALTERA_SPI_IDLE_VAL; 155 debug("%s: tx:%x ", __func__, d); 156 writel(d, &altspi->regs->txdata); 157 while (!(readl(&altspi->regs->status) & ALTERA_SPI_STATUS_RRDY_MSK)) 158 ; 159 d = readl(&altspi->regs->rxdata); 160 if (rxp) 161 *rxp++ = d; 162 debug("rx:%x\n", d); 163 } 164 done: 165 if (flags & SPI_XFER_END) 166 spi_cs_deactivate(slave); 167 168 return 0; 169 } 170