/* * Copyright 2006,2009 Freescale Semiconductor, Inc. * * 2012, Heiko Schocher, DENX Software Engineering, hs@denx.de. * Changes for multibus/multiadapter I2C support. * * SPDX-License-Identifier: GPL-2.0 */ #include #include #include /* Functional interface */ #include #include /* HW definitions */ #include #include /* The maximum number of microseconds we will wait until another master has * released the bus. If not defined in the board header file, then use a * generic value. */ #ifndef CONFIG_I2C_MBB_TIMEOUT #define CONFIG_I2C_MBB_TIMEOUT 100000 #endif /* The maximum number of microseconds we will wait for a read or write * operation to complete. If not defined in the board header file, then use a * generic value. */ #ifndef CONFIG_I2C_TIMEOUT #define CONFIG_I2C_TIMEOUT 100000 #endif #define I2C_READ_BIT 1 #define I2C_WRITE_BIT 0 DECLARE_GLOBAL_DATA_PTR; #ifndef CONFIG_DM_I2C static const struct fsl_i2c_base *i2c_base[4] = { (struct fsl_i2c_base *)(CONFIG_SYS_IMMR + CONFIG_SYS_FSL_I2C_OFFSET), #ifdef CONFIG_SYS_FSL_I2C2_OFFSET (struct fsl_i2c_base *)(CONFIG_SYS_IMMR + CONFIG_SYS_FSL_I2C2_OFFSET), #endif #ifdef CONFIG_SYS_FSL_I2C3_OFFSET (struct fsl_i2c_base *)(CONFIG_SYS_IMMR + CONFIG_SYS_FSL_I2C3_OFFSET), #endif #ifdef CONFIG_SYS_FSL_I2C4_OFFSET (struct fsl_i2c_base *)(CONFIG_SYS_IMMR + CONFIG_SYS_FSL_I2C4_OFFSET) #endif }; #endif /* I2C speed map for a DFSR value of 1 */ /* * Map I2C frequency dividers to FDR and DFSR values * * This structure is used to define the elements of a table that maps I2C * frequency divider (I2C clock rate divided by I2C bus speed) to a value to be * programmed into the Frequency Divider Ratio (FDR) and Digital Filter * Sampling Rate (DFSR) registers. * * The actual table should be defined in the board file, and it must be called * fsl_i2c_speed_map[]. * * The last entry of the table must have a value of {-1, X}, where X is same * FDR/DFSR values as the second-to-last entry. This guarantees that any * search through the array will always find a match. * * The values of the divider must be in increasing numerical order, i.e. * fsl_i2c_speed_map[x+1].divider > fsl_i2c_speed_map[x].divider. * * For this table, the values are based on a value of 1 for the DFSR * register. See the application note AN2919 "Determining the I2C Frequency * Divider Ratio for SCL" * * ColdFire I2C frequency dividers for FDR values are different from * PowerPC. The protocol to use the I2C module is still the same. * A different table is defined and are based on MCF5xxx user manual. * */ static const struct { unsigned short divider; u8 fdr; } fsl_i2c_speed_map[] = { #ifdef __M68K__ {20, 32}, {22, 33}, {24, 34}, {26, 35}, {28, 0}, {28, 36}, {30, 1}, {32, 37}, {34, 2}, {36, 38}, {40, 3}, {40, 39}, {44, 4}, {48, 5}, {48, 40}, {56, 6}, {56, 41}, {64, 42}, {68, 7}, {72, 43}, {80, 8}, {80, 44}, {88, 9}, {96, 41}, {104, 10}, {112, 42}, {128, 11}, {128, 43}, {144, 12}, {160, 13}, {160, 48}, {192, 14}, {192, 49}, {224, 50}, {240, 15}, {256, 51}, {288, 16}, {320, 17}, {320, 52}, {384, 18}, {384, 53}, {448, 54}, {480, 19}, {512, 55}, {576, 20}, {640, 21}, {640, 56}, {768, 22}, {768, 57}, {960, 23}, {896, 58}, {1024, 59}, {1152, 24}, {1280, 25}, {1280, 60}, {1536, 26}, {1536, 61}, {1792, 62}, {1920, 27}, {2048, 63}, {2304, 28}, {2560, 29}, {3072, 30}, {3840, 31}, {-1, 31} #endif }; /** * Set the I2C bus speed for a given I2C device * * @param base: the I2C device registers * @i2c_clk: I2C bus clock frequency * @speed: the desired speed of the bus * * The I2C device must be stopped before calling this function. * * The return value is the actual bus speed that is set. */ static unsigned int set_i2c_bus_speed(const struct fsl_i2c_base *base, unsigned int i2c_clk, unsigned int speed) { unsigned short divider = min(i2c_clk / speed, (unsigned int)USHRT_MAX); /* * We want to choose an FDR/DFSR that generates an I2C bus speed that * is equal to or lower than the requested speed. That means that we * want the first divider that is equal to or greater than the * calculated divider. */ #ifdef __PPC__ u8 dfsr, fdr = 0x31; /* Default if no FDR found */ /* a, b and dfsr matches identifiers A,B and C respectively in AN2919 */ unsigned short a, b, ga, gb; unsigned long c_div, est_div; #ifdef CONFIG_FSL_I2C_CUSTOM_DFSR dfsr = CONFIG_FSL_I2C_CUSTOM_DFSR; #else /* Condition 1: dfsr <= 50/T */ dfsr = (5 * (i2c_clk / 1000)) / 100000; #endif #ifdef CONFIG_FSL_I2C_CUSTOM_FDR fdr = CONFIG_FSL_I2C_CUSTOM_FDR; speed = i2c_clk / divider; /* Fake something */ #else debug("Requested speed:%d, i2c_clk:%d\n", speed, i2c_clk); if (!dfsr) dfsr = 1; est_div = ~0; for (ga = 0x4, a = 10; a <= 30; ga++, a += 2) { for (gb = 0; gb < 8; gb++) { b = 16 << gb; c_div = b * (a + ((3*dfsr)/b)*2); if ((c_div > divider) && (c_div < est_div)) { unsigned short bin_gb, bin_ga; est_div = c_div; bin_gb = gb << 2; bin_ga = (ga & 0x3) | ((ga & 0x4) << 3); fdr = bin_gb | bin_ga; speed = i2c_clk / est_div; debug("FDR:0x%.2x, div:%ld, ga:0x%x, gb:0x%x, " "a:%d, b:%d, speed:%d\n", fdr, est_div, ga, gb, a, b, speed); /* Condition 2 not accounted for */ debug("Tr <= %d ns\n", (b - 3 * dfsr) * 1000000 / (i2c_clk / 1000)); } } if (a == 20) a += 2; if (a == 24) a += 4; } debug("divider:%d, est_div:%ld, DFSR:%d\n", divider, est_div, dfsr); debug("FDR:0x%.2x, speed:%d\n", fdr, speed); #endif writeb(dfsr, &base->dfsrr); /* set default filter */ writeb(fdr, &base->fdr); /* set bus speed */ #else unsigned int i; for (i = 0; i < ARRAY_SIZE(fsl_i2c_speed_map); i++) if (fsl_i2c_speed_map[i].divider >= divider) { u8 fdr; fdr = fsl_i2c_speed_map[i].fdr; speed = i2c_clk / fsl_i2c_speed_map[i].divider; writeb(fdr, &base->fdr); /* set bus speed */ break; } #endif return speed; } #ifndef CONFIG_DM_I2C static unsigned int get_i2c_clock(int bus) { if (bus) return gd->arch.i2c2_clk; /* I2C2 clock */ else return gd->arch.i2c1_clk; /* I2C1 clock */ } #endif static int fsl_i2c_fixup(const struct fsl_i2c_base *base) { const unsigned long long timeout = usec2ticks(CONFIG_I2C_MBB_TIMEOUT); unsigned long long timeval = 0; int ret = -1; unsigned int flags = 0; #ifdef CONFIG_SYS_FSL_ERRATUM_I2C_A004447 unsigned int svr = get_svr(); if ((SVR_SOC_VER(svr) == SVR_8548 && IS_SVR_REV(svr, 3, 1)) || (SVR_REV(svr) <= CONFIG_SYS_FSL_A004447_SVR_REV)) flags = I2C_CR_BIT6; #endif writeb(I2C_CR_MEN | I2C_CR_MSTA, &base->cr); timeval = get_ticks(); while (!(readb(&base->sr) & I2C_SR_MBB)) { if ((get_ticks() - timeval) > timeout) goto err; } if (readb(&base->sr) & I2C_SR_MAL) { /* SDA is stuck low */ writeb(0, &base->cr); udelay(100); writeb(I2C_CR_MSTA | flags, &base->cr); writeb(I2C_CR_MEN | I2C_CR_MSTA | flags, &base->cr); } readb(&base->dr); timeval = get_ticks(); while (!(readb(&base->sr) & I2C_SR_MIF)) { if ((get_ticks() - timeval) > timeout) goto err; } ret = 0; err: writeb(I2C_CR_MEN | flags, &base->cr); writeb(0, &base->sr); udelay(100); return ret; } static void __i2c_init(const struct fsl_i2c_base *base, int speed, int slaveadd, int i2c_clk, int busnum) { const unsigned long long timeout = usec2ticks(CONFIG_I2C_MBB_TIMEOUT); unsigned long long timeval; #ifdef CONFIG_SYS_I2C_INIT_BOARD /* Call board specific i2c bus reset routine before accessing the * environment, which might be in a chip on that bus. For details * about this problem see doc/I2C_Edge_Conditions. */ i2c_init_board(); #endif writeb(0, &base->cr); /* stop I2C controller */ udelay(5); /* let it shutdown in peace */ set_i2c_bus_speed(base, i2c_clk, speed); writeb(slaveadd << 1, &base->adr);/* write slave address */ writeb(0x0, &base->sr); /* clear status register */ writeb(I2C_CR_MEN, &base->cr); /* start I2C controller */ timeval = get_ticks(); while (readb(&base->sr) & I2C_SR_MBB) { if ((get_ticks() - timeval) < timeout) continue; if (fsl_i2c_fixup(base)) debug("i2c_init: BUS#%d failed to init\n", busnum); break; } #ifdef CONFIG_SYS_I2C_BOARD_LATE_INIT /* Call board specific i2c bus reset routine AFTER the bus has been * initialized. Use either this callpoint or i2c_init_board; * which is called before i2c_init operations. * For details about this problem see doc/I2C_Edge_Conditions. */ i2c_board_late_init(); #endif } static int i2c_wait4bus(const struct fsl_i2c_base *base) { unsigned long long timeval = get_ticks(); const unsigned long long timeout = usec2ticks(CONFIG_I2C_MBB_TIMEOUT); while (readb(&base->sr) & I2C_SR_MBB) { if ((get_ticks() - timeval) > timeout) return -1; } return 0; } static inline int i2c_wait(const struct fsl_i2c_base *base, int write) { u32 csr; unsigned long long timeval = get_ticks(); const unsigned long long timeout = usec2ticks(CONFIG_I2C_TIMEOUT); do { csr = readb(&base->sr); if (!(csr & I2C_SR_MIF)) continue; /* Read again to allow register to stabilise */ csr = readb(&base->sr); writeb(0x0, &base->sr); if (csr & I2C_SR_MAL) { debug("i2c_wait: MAL\n"); return -1; } if (!(csr & I2C_SR_MCF)) { debug("i2c_wait: unfinished\n"); return -1; } if (write == I2C_WRITE_BIT && (csr & I2C_SR_RXAK)) { debug("i2c_wait: No RXACK\n"); return -1; } return 0; } while ((get_ticks() - timeval) < timeout); debug("i2c_wait: timed out\n"); return -1; } static inline int i2c_write_addr(const struct fsl_i2c_base *base, u8 dev, u8 dir, int rsta) { writeb(I2C_CR_MEN | I2C_CR_MSTA | I2C_CR_MTX | (rsta ? I2C_CR_RSTA : 0), &base->cr); writeb((dev << 1) | dir, &base->dr); if (i2c_wait(base, I2C_WRITE_BIT) < 0) return 0; return 1; } static inline int __i2c_write_data(const struct fsl_i2c_base *base, u8 *data, int length) { int i; for (i = 0; i < length; i++) { writeb(data[i], &base->dr); if (i2c_wait(base, I2C_WRITE_BIT) < 0) break; } return i; } static inline int __i2c_read_data(const struct fsl_i2c_base *base, u8 *data, int length) { int i; writeb(I2C_CR_MEN | I2C_CR_MSTA | ((length == 1) ? I2C_CR_TXAK : 0), &base->cr); /* dummy read */ readb(&base->dr); for (i = 0; i < length; i++) { if (i2c_wait(base, I2C_READ_BIT) < 0) break; /* Generate ack on last next to last byte */ if (i == length - 2) writeb(I2C_CR_MEN | I2C_CR_MSTA | I2C_CR_TXAK, &base->cr); /* Do not generate stop on last byte */ if (i == length - 1) writeb(I2C_CR_MEN | I2C_CR_MSTA | I2C_CR_MTX, &base->cr); data[i] = readb(&base->dr); } return i; } static int __i2c_read(const struct fsl_i2c_base *base, u8 chip_addr, u8 *offset, int olen, u8 *data, int dlen) { int ret = -1; /* signal error */ if (i2c_wait4bus(base) < 0) return -1; /* Some drivers use offset lengths in excess of 4 bytes. These drivers * adhere to the following convention: * - the offset length is passed as negative (that is, the absolute * value of olen is the actual offset length) * - the offset itself is passed in data, which is overwritten by the * subsequent read operation */ if (olen < 0) { if (i2c_write_addr(base, chip_addr, I2C_WRITE_BIT, 0) != 0) ret = __i2c_write_data(base, data, -olen); if (ret != -olen) return -1; if (dlen && i2c_write_addr(base, chip_addr, I2C_READ_BIT, 1) != 0) ret = __i2c_read_data(base, data, dlen); } else { if ((!dlen || olen > 0) && i2c_write_addr(base, chip_addr, I2C_WRITE_BIT, 0) != 0 && __i2c_write_data(base, offset, olen) == olen) ret = 0; /* No error so far */ if (dlen && i2c_write_addr(base, chip_addr, I2C_READ_BIT, olen ? 1 : 0) != 0) ret = __i2c_read_data(base, data, dlen); } writeb(I2C_CR_MEN, &base->cr); if (i2c_wait4bus(base)) /* Wait until STOP */ debug("i2c_read: wait4bus timed out\n"); if (ret == dlen) return 0; return -1; } static int __i2c_write(const struct fsl_i2c_base *base, u8 chip_addr, u8 *offset, int olen, u8 *data, int dlen) { int ret = -1; /* signal error */ if (i2c_wait4bus(base) < 0) return -1; if (i2c_write_addr(base, chip_addr, I2C_WRITE_BIT, 0) != 0 && __i2c_write_data(base, offset, olen) == olen) { ret = __i2c_write_data(base, data, dlen); } writeb(I2C_CR_MEN, &base->cr); if (i2c_wait4bus(base)) /* Wait until STOP */ debug("i2c_write: wait4bus timed out\n"); if (ret == dlen) return 0; return -1; } static int __i2c_probe_chip(const struct fsl_i2c_base *base, uchar chip) { /* For unknow reason the controller will ACK when * probing for a slave with the same address, so skip * it. */ if (chip == (readb(&base->adr) >> 1)) return -1; return __i2c_read(base, chip, 0, 0, NULL, 0); } static unsigned int __i2c_set_bus_speed(const struct fsl_i2c_base *base, unsigned int speed, int i2c_clk) { writeb(0, &base->cr); /* stop controller */ set_i2c_bus_speed(base, i2c_clk, speed); writeb(I2C_CR_MEN, &base->cr); /* start controller */ return 0; } #ifndef CONFIG_DM_I2C static void fsl_i2c_init(struct i2c_adapter *adap, int speed, int slaveadd) { __i2c_init(i2c_base[adap->hwadapnr], speed, slaveadd, get_i2c_clock(adap->hwadapnr), adap->hwadapnr); } static int fsl_i2c_probe_chip(struct i2c_adapter *adap, uchar chip) { return __i2c_probe_chip(i2c_base[adap->hwadapnr], chip); } static int fsl_i2c_read(struct i2c_adapter *adap, u8 chip_addr, uint offset, int olen, u8 *data, int dlen) { u8 *o = (u8 *)&offset; return __i2c_read(i2c_base[adap->hwadapnr], chip_addr, &o[4 - olen], olen, data, dlen); } static int fsl_i2c_write(struct i2c_adapter *adap, u8 chip_addr, uint offset, int olen, u8 *data, int dlen) { u8 *o = (u8 *)&offset; return __i2c_write(i2c_base[adap->hwadapnr], chip_addr, &o[4 - olen], olen, data, dlen); } static unsigned int fsl_i2c_set_bus_speed(struct i2c_adapter *adap, unsigned int speed) { return __i2c_set_bus_speed(i2c_base[adap->hwadapnr], speed, get_i2c_clock(adap->hwadapnr)); } /* * Register fsl i2c adapters */ U_BOOT_I2C_ADAP_COMPLETE(fsl_0, fsl_i2c_init, fsl_i2c_probe_chip, fsl_i2c_read, fsl_i2c_write, fsl_i2c_set_bus_speed, CONFIG_SYS_FSL_I2C_SPEED, CONFIG_SYS_FSL_I2C_SLAVE, 0) #ifdef CONFIG_SYS_FSL_I2C2_OFFSET U_BOOT_I2C_ADAP_COMPLETE(fsl_1, fsl_i2c_init, fsl_i2c_probe_chip, fsl_i2c_read, fsl_i2c_write, fsl_i2c_set_bus_speed, CONFIG_SYS_FSL_I2C2_SPEED, CONFIG_SYS_FSL_I2C2_SLAVE, 1) #endif #ifdef CONFIG_SYS_FSL_I2C3_OFFSET U_BOOT_I2C_ADAP_COMPLETE(fsl_2, fsl_i2c_init, fsl_i2c_probe_chip, fsl_i2c_read, fsl_i2c_write, fsl_i2c_set_bus_speed, CONFIG_SYS_FSL_I2C3_SPEED, CONFIG_SYS_FSL_I2C3_SLAVE, 2) #endif #ifdef CONFIG_SYS_FSL_I2C4_OFFSET U_BOOT_I2C_ADAP_COMPLETE(fsl_3, fsl_i2c_init, fsl_i2c_probe_chip, fsl_i2c_read, fsl_i2c_write, fsl_i2c_set_bus_speed, CONFIG_SYS_FSL_I2C4_SPEED, CONFIG_SYS_FSL_I2C4_SLAVE, 3) #endif #else /* CONFIG_DM_I2C */ static int fsl_i2c_probe_chip(struct udevice *bus, u32 chip_addr, u32 chip_flags) { struct fsl_i2c_dev *dev = dev_get_priv(bus); return __i2c_probe_chip(dev->base, chip_addr); } static int fsl_i2c_set_bus_speed(struct udevice *bus, unsigned int speed) { struct fsl_i2c_dev *dev = dev_get_priv(bus); return __i2c_set_bus_speed(dev->base, speed, dev->i2c_clk); } static int fsl_i2c_ofdata_to_platdata(struct udevice *bus) { struct fsl_i2c_dev *dev = dev_get_priv(bus); u64 reg; u32 addr, size; reg = fdtdec_get_addr(gd->fdt_blob, bus->of_offset, "reg"); addr = reg >> 32; size = reg & 0xFFFFFFFF; dev->base = map_sysmem(CONFIG_SYS_IMMR + addr, size); if (!dev->base) return -ENOMEM; dev->index = fdtdec_get_int(gd->fdt_blob, bus->of_offset, "cell-index", -1); dev->slaveadd = fdtdec_get_int(gd->fdt_blob, bus->of_offset, "u-boot,i2c-slave-addr", 0x7f); dev->speed = fdtdec_get_int(gd->fdt_blob, bus->of_offset, "clock-frequency", 400000); dev->i2c_clk = dev->index ? gd->arch.i2c2_clk : gd->arch.i2c1_clk; return 0; } static int fsl_i2c_probe(struct udevice *bus) { struct fsl_i2c_dev *dev = dev_get_priv(bus); __i2c_init(dev->base, dev->speed, dev->slaveadd, dev->i2c_clk, dev->index); return 0; } static int fsl_i2c_xfer(struct udevice *bus, struct i2c_msg *msg, int nmsgs) { struct fsl_i2c_dev *dev = dev_get_priv(bus); struct i2c_msg *dmsg, *omsg, dummy; memset(&dummy, 0, sizeof(struct i2c_msg)); /* We expect either two messages (one with an offset and one with the * actucal data) or one message (just data) */ if (nmsgs > 2 || nmsgs == 0) { debug("%s: Only one or two messages are supported.", __func__); return -1; } omsg = nmsgs == 1 ? &dummy : msg; dmsg = nmsgs == 1 ? msg : msg + 1; if (dmsg->flags & I2C_M_RD) return __i2c_read(dev->base, dmsg->addr, omsg->buf, omsg->len, dmsg->buf, dmsg->len); else return __i2c_write(dev->base, dmsg->addr, omsg->buf, omsg->len, dmsg->buf, dmsg->len); } static const struct dm_i2c_ops fsl_i2c_ops = { .xfer = fsl_i2c_xfer, .probe_chip = fsl_i2c_probe_chip, .set_bus_speed = fsl_i2c_set_bus_speed, }; static const struct udevice_id fsl_i2c_ids[] = { { .compatible = "fsl-i2c", }, { /* sentinel */ } }; U_BOOT_DRIVER(i2c_fsl) = { .name = "i2c_fsl", .id = UCLASS_I2C, .of_match = fsl_i2c_ids, .probe = fsl_i2c_probe, .ofdata_to_platdata = fsl_i2c_ofdata_to_platdata, .priv_auto_alloc_size = sizeof(struct fsl_i2c_dev), .ops = &fsl_i2c_ops, }; #endif /* CONFIG_DM_I2C */