1 /* 2 * (C) Copyright 2009 3 * Marvell Semiconductor <www.marvell.com> 4 * Written-by: Prafulla Wadaskar <prafulla@marvell.com> 5 * 6 * Derived from drivers/spi/mpc8xxx_spi.c 7 * 8 * See file CREDITS for list of people who contributed to this 9 * project. 10 * 11 * This program is free software; you can redistribute it and/or 12 * modify it under the terms of the GNU General Public License as 13 * published by the Free Software Foundation; either version 2 of 14 * the License, or (at your option) any later version. 15 * 16 * This program is distributed in the hope that it will be useful, 17 * but WITHOUT ANY WARRANTY; without even the implied warranty of 18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 19 * GNU General Public License for more details. 20 * 21 * You should have received a copy of the GNU General Public License 22 * along with this program; if not, write to the Free Software 23 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, 24 * MA 02110-1301 USA 25 */ 26 27 #include <common.h> 28 #include <malloc.h> 29 #include <spi.h> 30 #include <asm/io.h> 31 #include <asm/arch/kirkwood.h> 32 #include <asm/arch/spi.h> 33 #include <asm/arch/mpp.h> 34 35 static struct kwspi_registers *spireg = (struct kwspi_registers *)KW_SPI_BASE; 36 37 u32 cs_spi_mpp_back[2]; 38 39 struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs, 40 unsigned int max_hz, unsigned int mode) 41 { 42 struct spi_slave *slave; 43 u32 data; 44 u32 kwspi_mpp_config[] = { 0, 0 }; 45 46 if (!spi_cs_is_valid(bus, cs)) 47 return NULL; 48 49 slave = malloc(sizeof(struct spi_slave)); 50 if (!slave) 51 return NULL; 52 53 slave->bus = bus; 54 slave->cs = cs; 55 56 writel(~KWSPI_CSN_ACT | KWSPI_SMEMRDY, &spireg->ctrl); 57 58 /* calculate spi clock prescaller using max_hz */ 59 data = ((CONFIG_SYS_TCLK / 2) / max_hz) & KWSPI_CLKPRESCL_MASK; 60 data |= 0x10; 61 62 /* program spi clock prescaller using max_hz */ 63 writel(KWSPI_ADRLEN_3BYTE | data, &spireg->cfg); 64 debug("data = 0x%08x \n", data); 65 66 writel(KWSPI_SMEMRDIRQ, &spireg->irq_cause); 67 writel(KWSPI_IRQMASK, &spireg->irq_mask); 68 69 /* program mpp registers to select SPI_CSn */ 70 if (cs) { 71 kwspi_mpp_config[0] = MPP7_SPI_SCn; 72 } else { 73 kwspi_mpp_config[0] = MPP0_SPI_SCn; 74 } 75 kirkwood_mpp_conf(kwspi_mpp_config, cs_spi_mpp_back); 76 77 return slave; 78 } 79 80 void spi_free_slave(struct spi_slave *slave) 81 { 82 kirkwood_mpp_conf(cs_spi_mpp_back, NULL); 83 free(slave); 84 } 85 86 #if defined(CONFIG_SYS_KW_SPI_MPP) 87 u32 spi_mpp_backup[4]; 88 #endif 89 90 __attribute__((weak)) int board_spi_claim_bus(struct spi_slave *slave) 91 { 92 return 0; 93 } 94 95 int spi_claim_bus(struct spi_slave *slave) 96 { 97 #if defined(CONFIG_SYS_KW_SPI_MPP) 98 u32 config; 99 u32 spi_mpp_config[4]; 100 101 config = CONFIG_SYS_KW_SPI_MPP; 102 103 if (config & MOSI_MPP6) 104 spi_mpp_config[0] = MPP6_SPI_MOSI; 105 else 106 spi_mpp_config[0] = MPP1_SPI_MOSI; 107 108 if (config & SCK_MPP10) 109 spi_mpp_config[1] = MPP10_SPI_SCK; 110 else 111 spi_mpp_config[1] = MPP2_SPI_SCK; 112 113 if (config & MISO_MPP11) 114 spi_mpp_config[2] = MPP11_SPI_MISO; 115 else 116 spi_mpp_config[2] = MPP3_SPI_MISO; 117 118 spi_mpp_config[3] = 0; 119 spi_mpp_backup[3] = 0; 120 121 /* set new spi mpp and save current mpp config */ 122 kirkwood_mpp_conf(spi_mpp_config, spi_mpp_backup); 123 124 #endif 125 126 return board_spi_claim_bus(slave); 127 } 128 129 __attribute__((weak)) void board_spi_release_bus(struct spi_slave *slave) 130 { 131 } 132 133 void spi_release_bus(struct spi_slave *slave) 134 { 135 #if defined(CONFIG_SYS_KW_SPI_MPP) 136 kirkwood_mpp_conf(spi_mpp_backup, NULL); 137 #endif 138 139 board_spi_release_bus(slave); 140 } 141 142 #ifndef CONFIG_SPI_CS_IS_VALID 143 /* 144 * you can define this function board specific 145 * define above CONFIG in board specific config file and 146 * provide the function in board specific src file 147 */ 148 int spi_cs_is_valid(unsigned int bus, unsigned int cs) 149 { 150 return (bus == 0 && (cs == 0 || cs == 1)); 151 } 152 #endif 153 154 void spi_init(void) 155 { 156 } 157 158 void spi_cs_activate(struct spi_slave *slave) 159 { 160 writel(readl(&spireg->ctrl) | KWSPI_IRQUNMASK, &spireg->ctrl); 161 } 162 163 void spi_cs_deactivate(struct spi_slave *slave) 164 { 165 writel(readl(&spireg->ctrl) & KWSPI_IRQMASK, &spireg->ctrl); 166 } 167 168 int spi_xfer(struct spi_slave *slave, unsigned int bitlen, const void *dout, 169 void *din, unsigned long flags) 170 { 171 unsigned int tmpdout, tmpdin; 172 int tm, isread = 0; 173 174 debug("spi_xfer: slave %u:%u dout %p din %p bitlen %u\n", 175 slave->bus, slave->cs, dout, din, bitlen); 176 177 if (flags & SPI_XFER_BEGIN) 178 spi_cs_activate(slave); 179 180 /* 181 * handle data in 8-bit chunks 182 * TBD: 2byte xfer mode to be enabled 183 */ 184 writel(((readl(&spireg->cfg) & ~KWSPI_XFERLEN_MASK) | 185 KWSPI_XFERLEN_1BYTE), &spireg->cfg); 186 187 while (bitlen > 4) { 188 debug("loopstart bitlen %d\n", bitlen); 189 tmpdout = 0; 190 191 /* Shift data so it's msb-justified */ 192 if (dout) 193 tmpdout = *(u32 *) dout & 0x0ff; 194 195 writel(~KWSPI_SMEMRDIRQ, &spireg->irq_cause); 196 writel(tmpdout, &spireg->dout); /* Write the data out */ 197 debug("*** spi_xfer: ... %08x written, bitlen %d\n", 198 tmpdout, bitlen); 199 200 /* 201 * Wait for SPI transmit to get out 202 * or time out (1 second = 1000 ms) 203 * The NE event must be read and cleared first 204 */ 205 for (tm = 0, isread = 0; tm < KWSPI_TIMEOUT; ++tm) { 206 if (readl(&spireg->irq_cause) & KWSPI_SMEMRDIRQ) { 207 isread = 1; 208 tmpdin = readl(&spireg->din); 209 debug 210 ("spi_xfer: din %p..%08x read\n", 211 din, tmpdin); 212 213 if (din) { 214 *((u8 *) din) = (u8) tmpdin; 215 din += 1; 216 } 217 if (dout) 218 dout += 1; 219 bitlen -= 8; 220 } 221 if (isread) 222 break; 223 } 224 if (tm >= KWSPI_TIMEOUT) 225 printf("*** spi_xfer: Time out during SPI transfer\n"); 226 227 debug("loopend bitlen %d\n", bitlen); 228 } 229 230 if (flags & SPI_XFER_END) 231 spi_cs_deactivate(slave); 232 233 return 0; 234 } 235