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) + 0x10; 60 data = data < KWSPI_CLKPRESCL_MIN ? KWSPI_CLKPRESCL_MIN : data; 61 data = data > KWSPI_CLKPRESCL_MASK ? KWSPI_CLKPRESCL_MASK : data; 62 63 /* program spi clock prescaller using max_hz */ 64 writel(KWSPI_ADRLEN_3BYTE | data, &spireg->cfg); 65 debug("data = 0x%08x \n", data); 66 67 writel(KWSPI_SMEMRDIRQ, &spireg->irq_cause); 68 writel(KWSPI_IRQMASK, &spireg->irq_mask); 69 70 /* program mpp registers to select SPI_CSn */ 71 if (cs) { 72 kwspi_mpp_config[0] = MPP7_SPI_SCn; 73 } else { 74 kwspi_mpp_config[0] = MPP0_SPI_SCn; 75 } 76 kirkwood_mpp_conf(kwspi_mpp_config, cs_spi_mpp_back); 77 78 return slave; 79 } 80 81 void spi_free_slave(struct spi_slave *slave) 82 { 83 kirkwood_mpp_conf(cs_spi_mpp_back, NULL); 84 free(slave); 85 } 86 87 #if defined(CONFIG_SYS_KW_SPI_MPP) 88 u32 spi_mpp_backup[4]; 89 #endif 90 91 __attribute__((weak)) int board_spi_claim_bus(struct spi_slave *slave) 92 { 93 return 0; 94 } 95 96 int spi_claim_bus(struct spi_slave *slave) 97 { 98 #if defined(CONFIG_SYS_KW_SPI_MPP) 99 u32 config; 100 u32 spi_mpp_config[4]; 101 102 config = CONFIG_SYS_KW_SPI_MPP; 103 104 if (config & MOSI_MPP6) 105 spi_mpp_config[0] = MPP6_SPI_MOSI; 106 else 107 spi_mpp_config[0] = MPP1_SPI_MOSI; 108 109 if (config & SCK_MPP10) 110 spi_mpp_config[1] = MPP10_SPI_SCK; 111 else 112 spi_mpp_config[1] = MPP2_SPI_SCK; 113 114 if (config & MISO_MPP11) 115 spi_mpp_config[2] = MPP11_SPI_MISO; 116 else 117 spi_mpp_config[2] = MPP3_SPI_MISO; 118 119 spi_mpp_config[3] = 0; 120 spi_mpp_backup[3] = 0; 121 122 /* set new spi mpp and save current mpp config */ 123 kirkwood_mpp_conf(spi_mpp_config, spi_mpp_backup); 124 125 #endif 126 127 return board_spi_claim_bus(slave); 128 } 129 130 __attribute__((weak)) void board_spi_release_bus(struct spi_slave *slave) 131 { 132 } 133 134 void spi_release_bus(struct spi_slave *slave) 135 { 136 #if defined(CONFIG_SYS_KW_SPI_MPP) 137 kirkwood_mpp_conf(spi_mpp_backup, NULL); 138 #endif 139 140 board_spi_release_bus(slave); 141 } 142 143 #ifndef CONFIG_SPI_CS_IS_VALID 144 /* 145 * you can define this function board specific 146 * define above CONFIG in board specific config file and 147 * provide the function in board specific src file 148 */ 149 int spi_cs_is_valid(unsigned int bus, unsigned int cs) 150 { 151 return (bus == 0 && (cs == 0 || cs == 1)); 152 } 153 #endif 154 155 void spi_init(void) 156 { 157 } 158 159 void spi_cs_activate(struct spi_slave *slave) 160 { 161 writel(readl(&spireg->ctrl) | KWSPI_IRQUNMASK, &spireg->ctrl); 162 } 163 164 void spi_cs_deactivate(struct spi_slave *slave) 165 { 166 writel(readl(&spireg->ctrl) & KWSPI_IRQMASK, &spireg->ctrl); 167 } 168 169 int spi_xfer(struct spi_slave *slave, unsigned int bitlen, const void *dout, 170 void *din, unsigned long flags) 171 { 172 unsigned int tmpdout, tmpdin; 173 int tm, isread = 0; 174 175 debug("spi_xfer: slave %u:%u dout %p din %p bitlen %u\n", 176 slave->bus, slave->cs, dout, din, bitlen); 177 178 if (flags & SPI_XFER_BEGIN) 179 spi_cs_activate(slave); 180 181 /* 182 * handle data in 8-bit chunks 183 * TBD: 2byte xfer mode to be enabled 184 */ 185 writel(((readl(&spireg->cfg) & ~KWSPI_XFERLEN_MASK) | 186 KWSPI_XFERLEN_1BYTE), &spireg->cfg); 187 188 while (bitlen > 4) { 189 debug("loopstart bitlen %d\n", bitlen); 190 tmpdout = 0; 191 192 /* Shift data so it's msb-justified */ 193 if (dout) 194 tmpdout = *(u32 *) dout & 0x0ff; 195 196 writel(~KWSPI_SMEMRDIRQ, &spireg->irq_cause); 197 writel(tmpdout, &spireg->dout); /* Write the data out */ 198 debug("*** spi_xfer: ... %08x written, bitlen %d\n", 199 tmpdout, bitlen); 200 201 /* 202 * Wait for SPI transmit to get out 203 * or time out (1 second = 1000 ms) 204 * The NE event must be read and cleared first 205 */ 206 for (tm = 0, isread = 0; tm < KWSPI_TIMEOUT; ++tm) { 207 if (readl(&spireg->irq_cause) & KWSPI_SMEMRDIRQ) { 208 isread = 1; 209 tmpdin = readl(&spireg->din); 210 debug 211 ("spi_xfer: din %p..%08x read\n", 212 din, tmpdin); 213 214 if (din) { 215 *((u8 *) din) = (u8) tmpdin; 216 din += 1; 217 } 218 if (dout) 219 dout += 1; 220 bitlen -= 8; 221 } 222 if (isread) 223 break; 224 } 225 if (tm >= KWSPI_TIMEOUT) 226 printf("*** spi_xfer: Time out during SPI transfer\n"); 227 228 debug("loopend bitlen %d\n", bitlen); 229 } 230 231 if (flags & SPI_XFER_END) 232 spi_cs_deactivate(slave); 233 234 return 0; 235 } 236