From f9ce2eddf1769a2cf93e87332c55063537e69119 Mon Sep 17 00:00:00 2001 From: Boris Brezillon Date: Thu, 16 Mar 2017 09:35:59 +0100 Subject: [PATCH 1/1] mtd: nand: atmel: Add ->setup_data_interface() hooks The NAND controller IP can adapt the NAND controller timings dynamically. Implement the ->setup_data_interface() hook to support this feature. Note that it's not supported on at91rm9200 because this SoC has a completely different SMC block, which is not supported yet. Signed-off-by: Boris Brezillon --- drivers/mtd/nand/Kconfig | 1 + drivers/mtd/nand/atmel/nand-controller.c | 329 ++++++++++++++++++++++- 2 files changed, 328 insertions(+), 2 deletions(-) diff --git a/drivers/mtd/nand/Kconfig b/drivers/mtd/nand/Kconfig index 0bd2319d3035..dbfa72d61d5a 100644 --- a/drivers/mtd/nand/Kconfig +++ b/drivers/mtd/nand/Kconfig @@ -308,6 +308,7 @@ config MTD_NAND_CS553X config MTD_NAND_ATMEL tristate "Support for NAND Flash / SmartMedia on AT91" depends on ARCH_AT91 + select MFD_ATMEL_SMC help Enables support for NAND Flash / Smart Media Card interface on Atmel AT91 processors. diff --git a/drivers/mtd/nand/atmel/nand-controller.c b/drivers/mtd/nand/atmel/nand-controller.c index 3b2446896147..ee32909f7943 100644 --- a/drivers/mtd/nand/atmel/nand-controller.c +++ b/drivers/mtd/nand/atmel/nand-controller.c @@ -57,6 +57,7 @@ #include #include #include +#include #include #include #include @@ -151,6 +152,8 @@ struct atmel_nand_cs { void __iomem *virt; dma_addr_t dma; } io; + + struct atmel_smc_cs_conf smcconf; }; struct atmel_nand { @@ -196,6 +199,8 @@ struct atmel_nand_controller_ops { void (*nand_init)(struct atmel_nand_controller *nc, struct atmel_nand *nand); int (*ecc_init)(struct atmel_nand *nand); + int (*setup_data_interface)(struct atmel_nand *nand, int csline, + const struct nand_data_interface *conf); }; struct atmel_nand_controller_caps { @@ -1175,6 +1180,295 @@ static int atmel_hsmc_nand_ecc_init(struct atmel_nand *nand) return 0; } +static int atmel_smc_nand_prepare_smcconf(struct atmel_nand *nand, + const struct nand_data_interface *conf, + struct atmel_smc_cs_conf *smcconf) +{ + u32 ncycles, totalcycles, timeps, mckperiodps; + struct atmel_nand_controller *nc; + int ret; + + nc = to_nand_controller(nand->base.controller); + + /* DDR interface not supported. */ + if (conf->type != NAND_SDR_IFACE) + return -ENOTSUPP; + + /* + * tRC < 30ns implies EDO mode. This controller does not support this + * mode. + */ + if (conf->timings.sdr.tRC_min < 30) + return -ENOTSUPP; + + atmel_smc_cs_conf_init(smcconf); + + mckperiodps = NSEC_PER_SEC / clk_get_rate(nc->mck); + mckperiodps *= 1000; + + /* + * Set write pulse timing. This one is easy to extract: + * + * NWE_PULSE = tWP + */ + ncycles = DIV_ROUND_UP(conf->timings.sdr.tWP_min, mckperiodps); + totalcycles = ncycles; + ret = atmel_smc_cs_conf_set_pulse(smcconf, ATMEL_SMC_NWE_SHIFT, + ncycles); + if (ret) + return ret; + + /* + * The write setup timing depends on the operation done on the NAND. + * All operations goes through the same data bus, but the operation + * type depends on the address we are writing to (ALE/CLE address + * lines). + * Since we have no way to differentiate the different operations at + * the SMC level, we must consider the worst case (the biggest setup + * time among all operation types): + * + * NWE_SETUP = max(tCLS, tCS, tALS, tDS) - NWE_PULSE + */ + timeps = max3(conf->timings.sdr.tCLS_min, conf->timings.sdr.tCS_min, + conf->timings.sdr.tALS_min); + timeps = max(timeps, conf->timings.sdr.tDS_min); + ncycles = DIV_ROUND_UP(timeps, mckperiodps); + ncycles = ncycles > totalcycles ? ncycles - totalcycles : 0; + totalcycles += ncycles; + ret = atmel_smc_cs_conf_set_setup(smcconf, ATMEL_SMC_NWE_SHIFT, + ncycles); + if (ret) + return ret; + + /* + * As for the write setup timing, the write hold timing depends on the + * operation done on the NAND: + * + * NWE_HOLD = max(tCLH, tCH, tALH, tDH, tWH) + */ + timeps = max3(conf->timings.sdr.tCLH_min, conf->timings.sdr.tCH_min, + conf->timings.sdr.tALH_min); + timeps = max3(timeps, conf->timings.sdr.tDH_min, + conf->timings.sdr.tWH_min); + ncycles = DIV_ROUND_UP(timeps, mckperiodps); + totalcycles += ncycles; + + /* + * The write cycle timing is directly matching tWC, but is also + * dependent on the other timings on the setup and hold timings we + * calculated earlier, which gives: + * + * NWE_CYCLE = max(tWC, NWE_SETUP + NWE_PULSE + NWE_HOLD) + */ + ncycles = DIV_ROUND_UP(conf->timings.sdr.tWC_min, mckperiodps); + ncycles = max(totalcycles, ncycles); + ret = atmel_smc_cs_conf_set_cycle(smcconf, ATMEL_SMC_NWE_SHIFT, + ncycles); + if (ret) + return ret; + + /* + * We don't want the CS line to be toggled between each byte/word + * transfer to the NAND. The only way to guarantee that is to have the + * NCS_{WR,RD}_{SETUP,HOLD} timings set to 0, which in turn means: + * + * NCS_WR_PULSE = NWE_CYCLE + */ + ret = atmel_smc_cs_conf_set_pulse(smcconf, ATMEL_SMC_NCS_WR_SHIFT, + ncycles); + if (ret) + return ret; + + /* + * As for the write setup timing, the read hold timing depends on the + * operation done on the NAND: + * + * NRD_HOLD = max(tREH, tRHOH) + */ + timeps = max(conf->timings.sdr.tREH_min, conf->timings.sdr.tRHOH_min); + ncycles = DIV_ROUND_UP(timeps, mckperiodps); + totalcycles = ncycles; + + /* + * TDF = tRHZ - NRD_HOLD + */ + ncycles = DIV_ROUND_UP(conf->timings.sdr.tRHZ_max, mckperiodps); + ncycles -= totalcycles; + + /* + * In ONFI 4.0 specs, tRHZ has been increased to support EDO NANDs and + * we might end up with a config that does not fit in the TDF field. + * Just take the max value in this case and hope that the NAND is more + * tolerant than advertised. + */ + if (ncycles > ATMEL_SMC_MODE_TDF_MAX) + ncycles = ATMEL_SMC_MODE_TDF_MAX; + else if (ncycles < ATMEL_SMC_MODE_TDF_MIN) + ncycles = ATMEL_SMC_MODE_TDF_MIN; + + smcconf->mode |= ATMEL_SMC_MODE_TDF(ncycles) | + ATMEL_SMC_MODE_TDFMODE_OPTIMIZED; + + /* + * Read pulse timing directly matches tRP: + * + * NRD_PULSE = tRP + */ + ncycles = DIV_ROUND_UP(conf->timings.sdr.tRP_min, mckperiodps); + totalcycles += ncycles; + ret = atmel_smc_cs_conf_set_pulse(smcconf, ATMEL_SMC_NRD_SHIFT, + ncycles); + if (ret) + return ret; + + /* + * The write cycle timing is directly matching tWC, but is also + * dependent on the setup and hold timings we calculated earlier, + * which gives: + * + * NRD_CYCLE = max(tRC, NRD_PULSE + NRD_HOLD) + * + * NRD_SETUP is always 0. + */ + ncycles = DIV_ROUND_UP(conf->timings.sdr.tRC_min, mckperiodps); + ncycles = max(totalcycles, ncycles); + ret = atmel_smc_cs_conf_set_cycle(smcconf, ATMEL_SMC_NRD_SHIFT, + ncycles); + if (ret) + return ret; + + /* + * We don't want the CS line to be toggled between each byte/word + * transfer from the NAND. The only way to guarantee that is to have + * the NCS_{WR,RD}_{SETUP,HOLD} timings set to 0, which in turn means: + * + * NCS_RD_PULSE = NRD_CYCLE + */ + ret = atmel_smc_cs_conf_set_pulse(smcconf, ATMEL_SMC_NCS_RD_SHIFT, + ncycles); + if (ret) + return ret; + + /* Txxx timings are directly matching tXXX ones. */ + ncycles = DIV_ROUND_UP(conf->timings.sdr.tCLR_min, mckperiodps); + ret = atmel_smc_cs_conf_set_timing(smcconf, + ATMEL_HSMC_TIMINGS_TCLR_SHIFT, + ncycles); + if (ret) + return ret; + + ncycles = DIV_ROUND_UP(conf->timings.sdr.tADL_min, mckperiodps); + ret = atmel_smc_cs_conf_set_timing(smcconf, + ATMEL_HSMC_TIMINGS_TADL_SHIFT, + ncycles); + if (ret) + return ret; + + ncycles = DIV_ROUND_UP(conf->timings.sdr.tAR_min, mckperiodps); + ret = atmel_smc_cs_conf_set_timing(smcconf, + ATMEL_HSMC_TIMINGS_TAR_SHIFT, + ncycles); + if (ret) + return ret; + + ncycles = DIV_ROUND_UP(conf->timings.sdr.tRR_min, mckperiodps); + ret = atmel_smc_cs_conf_set_timing(smcconf, + ATMEL_HSMC_TIMINGS_TRR_SHIFT, + ncycles); + if (ret) + return ret; + + ncycles = DIV_ROUND_UP(conf->timings.sdr.tWB_max, mckperiodps); + ret = atmel_smc_cs_conf_set_timing(smcconf, + ATMEL_HSMC_TIMINGS_TWB_SHIFT, + ncycles); + if (ret) + return ret; + + /* Attach the CS line to the NFC logic. */ + smcconf->timings |= ATMEL_HSMC_TIMINGS_NFSEL; + + /* Set the appropriate data bus width. */ + if (nand->base.options & NAND_BUSWIDTH_16) + smcconf->mode |= ATMEL_SMC_MODE_DBW_16; + + /* Operate in NRD/NWE READ/WRITEMODE. */ + smcconf->mode |= ATMEL_SMC_MODE_READMODE_NRD | + ATMEL_SMC_MODE_WRITEMODE_NWE; + + return 0; +} + +static int atmel_smc_nand_setup_data_interface(struct atmel_nand *nand, + int csline, + const struct nand_data_interface *conf) +{ + struct atmel_nand_controller *nc; + struct atmel_smc_cs_conf smcconf; + struct atmel_nand_cs *cs; + int ret; + + nc = to_nand_controller(nand->base.controller); + + ret = atmel_smc_nand_prepare_smcconf(nand, conf, &smcconf); + if (ret) + return ret; + + if (csline == NAND_DATA_IFACE_CHECK_ONLY) + return 0; + + cs = &nand->cs[csline]; + cs->smcconf = smcconf; + atmel_smc_cs_conf_apply(nc->smc, cs->id, &cs->smcconf); + + return 0; +} + +static int atmel_hsmc_nand_setup_data_interface(struct atmel_nand *nand, + int csline, + const struct nand_data_interface *conf) +{ + struct atmel_nand_controller *nc; + struct atmel_smc_cs_conf smcconf; + struct atmel_nand_cs *cs; + int ret; + + nc = to_nand_controller(nand->base.controller); + + ret = atmel_smc_nand_prepare_smcconf(nand, conf, &smcconf); + if (ret) + return ret; + + if (csline == NAND_DATA_IFACE_CHECK_ONLY) + return 0; + + cs = &nand->cs[csline]; + cs->smcconf = smcconf; + + if (cs->rb.type == ATMEL_NAND_NATIVE_RB) + cs->smcconf.timings |= ATMEL_HSMC_TIMINGS_RBNSEL(cs->rb.id); + + atmel_hsmc_cs_conf_apply(nc->smc, cs->id, &cs->smcconf); + + return 0; +} + +static int atmel_nand_setup_data_interface(struct mtd_info *mtd, int csline, + const struct nand_data_interface *conf) +{ + struct nand_chip *chip = mtd_to_nand(mtd); + struct atmel_nand *nand = to_atmel_nand(chip); + struct atmel_nand_controller *nc; + + nc = to_nand_controller(nand->base.controller); + + if (csline >= nand->numcs || + (csline < 0 && csline != NAND_DATA_IFACE_CHECK_ONLY)) + return -EINVAL; + + return nc->caps->ops->setup_data_interface(nand, csline, conf); +} + static void atmel_nand_init(struct atmel_nand_controller *nc, struct atmel_nand *nand) { @@ -1192,6 +1486,9 @@ static void atmel_nand_init(struct atmel_nand_controller *nc, chip->write_buf = atmel_nand_write_buf; chip->select_chip = atmel_nand_select_chip; + if (nc->mck && nc->caps->ops->setup_data_interface) + chip->setup_data_interface = atmel_nand_setup_data_interface; + /* Some NANDs require a longer delay than the default one (20us). */ chip->chip_delay = 40; @@ -1677,6 +1974,12 @@ static int atmel_nand_controller_init(struct atmel_nand_controller *nc, if (nc->caps->legacy_of_bindings) return 0; + nc->mck = of_clk_get(dev->parent->of_node, 0); + if (IS_ERR(nc->mck)) { + dev_err(dev, "Failed to retrieve MCK clk\n"); + return PTR_ERR(nc->mck); + } + np = of_parse_phandle(dev->parent->of_node, "atmel,smc", 0); if (!np) { dev_err(dev, "Missing or invalid atmel,smc property\n"); @@ -1983,6 +2286,7 @@ static const struct atmel_nand_controller_ops atmel_hsmc_nc_ops = { .remove = atmel_hsmc_nand_controller_remove, .ecc_init = atmel_hsmc_nand_ecc_init, .nand_init = atmel_hsmc_nand_init, + .setup_data_interface = atmel_hsmc_nand_setup_data_interface, }; static const struct atmel_nand_controller_caps atmel_sama5_nc_caps = { @@ -2037,7 +2341,14 @@ atmel_smc_nand_controller_remove(struct atmel_nand_controller *nc) return 0; } -static const struct atmel_nand_controller_ops atmel_smc_nc_ops = { +/* + * The SMC reg layout of at91rm9200 is completely different which prevents us + * from re-using atmel_smc_nand_setup_data_interface() for the + * ->setup_data_interface() hook. + * At this point, there's no support for the at91rm9200 SMC IP, so we leave + * ->setup_data_interface() unassigned. + */ +static const struct atmel_nand_controller_ops at91rm9200_nc_ops = { .probe = atmel_smc_nand_controller_probe, .remove = atmel_smc_nand_controller_remove, .ecc_init = atmel_nand_ecc_init, @@ -2045,6 +2356,20 @@ static const struct atmel_nand_controller_ops atmel_smc_nc_ops = { }; static const struct atmel_nand_controller_caps atmel_rm9200_nc_caps = { + .ale_offs = BIT(21), + .cle_offs = BIT(22), + .ops = &at91rm9200_nc_ops, +}; + +static const struct atmel_nand_controller_ops atmel_smc_nc_ops = { + .probe = atmel_smc_nand_controller_probe, + .remove = atmel_smc_nand_controller_remove, + .ecc_init = atmel_nand_ecc_init, + .nand_init = atmel_smc_nand_init, + .setup_data_interface = atmel_smc_nand_setup_data_interface, +}; + +static const struct atmel_nand_controller_caps atmel_sam9260_nc_caps = { .ale_offs = BIT(21), .cle_offs = BIT(22), .ops = &atmel_smc_nc_ops, @@ -2093,7 +2418,7 @@ static const struct of_device_id atmel_nand_controller_of_ids[] = { }, { .compatible = "atmel,at91sam9260-nand-controller", - .data = &atmel_rm9200_nc_caps, + .data = &atmel_sam9260_nc_caps, }, { .compatible = "atmel,at91sam9261-nand-controller", -- 2.39.2