Merge tag 'at91-ab-4.8-drivers' of git://git.kernel.org/pub/scm/linux/kernel/git...
authorOlof Johansson <olof@lixom.net>
Tue, 14 Jun 2016 17:18:54 +0000 (10:18 -0700)
committerOlof Johansson <olof@lixom.net>
Tue, 14 Jun 2016 17:18:54 +0000 (10:18 -0700)
Drivers for 4.8:
 - Add a driver for the EBI

* tag 'at91-ab-4.8-drivers' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux:
  memory: atmel-ebi: add DT bindings documentation
  memory: add Atmel EBI (External Bus Interface) driver

Signed-off-by: Olof Johansson <olof@lixom.net>
Documentation/devicetree/bindings/memory-controllers/atmel,ebi.txt [new file with mode: 0644]
drivers/memory/Kconfig
drivers/memory/Makefile
drivers/memory/atmel-ebi.c [new file with mode: 0644]

diff --git a/Documentation/devicetree/bindings/memory-controllers/atmel,ebi.txt b/Documentation/devicetree/bindings/memory-controllers/atmel,ebi.txt
new file mode 100644 (file)
index 0000000..9bb5f57
--- /dev/null
@@ -0,0 +1,136 @@
+* Device tree bindings for Atmel EBI
+
+The External Bus Interface (EBI) controller is a bus where you can connect
+asynchronous (NAND, NOR, SRAM, ....) and synchronous memories (SDR/DDR SDRAMs).
+The EBI provides a glue-less interface to asynchronous memories through the SMC
+(Static Memory Controller).
+
+Required properties:
+
+- compatible:          "atmel,at91sam9260-ebi"
+                       "atmel,at91sam9261-ebi"
+                       "atmel,at91sam9263-ebi0"
+                       "atmel,at91sam9263-ebi1"
+                       "atmel,at91sam9rl-ebi"
+                       "atmel,at91sam9g45-ebi"
+                       "atmel,at91sam9x5-ebi"
+                       "atmel,sama5d3-ebi"
+
+- reg:                 Contains offset/length value for EBI memory mapping.
+                       This property might contain several entries if the EBI
+                       memory range is not contiguous
+
+- #address-cells:      Must be 2.
+                       The first cell encodes the CS.
+                       The second cell encode the offset into the CS memory
+                       range.
+
+- #size-cells:         Must be set to 1.
+
+- ranges:              Encodes CS to memory region association.
+
+- clocks:              Clock feeding the EBI controller.
+                       See clock-bindings.txt
+
+Children device nodes are representing device connected to the EBI bus.
+
+Required device node properties:
+
+- reg:                 Contains the chip-select id, the offset and the length
+                       of the memory region requested by the device.
+
+EBI bus configuration will be defined directly in the device subnode.
+
+Optional EBI/SMC properties:
+
+- atmel,smc-bus-width:         width of the asynchronous device's data bus
+                               8, 16 or 32.
+                               Default to 8 when undefined.
+
+- atmel,smc-byte-access-type   "write" or "select" (see Atmel datasheet).
+                               Default to "select" when undefined.
+
+- atmel,smc-read-mode          "nrd" or "ncs".
+                               Default to "ncs" when undefined.
+
+- atmel,smc-write-mode         "nwe" or "ncs".
+                               Default to "ncs" when undefined.
+
+- atmel,smc-exnw-mode          "disabled", "frozen" or "ready".
+                               Default to "disabled" when undefined.
+
+- atmel,smc-page-mode          enable page mode if present. The provided value
+                               defines the page size (supported values: 4, 8,
+                               16 and 32).
+
+- atmel,smc-tdf-mode:          "normal" or "optimized". When set to
+                               "optimized" the data float time is optimized
+                               depending on the next device being accessed
+                               (next device setup time is subtracted to the
+                               current device data float time).
+                               Default to "normal" when undefined.
+
+If at least one atmel,smc- property is defined the following SMC timing
+properties become mandatory. In the other hand, if none of the atmel,smc-
+properties are specified, we assume that the EBI bus configuration will be
+handled by the sub-device driver, and none of those properties should be
+defined.
+
+All the timings are expressed in nanoseconds (see Atmel datasheet for a full
+description).
+
+- atmel,smc-ncs-rd-setup-ns
+- atmel,smc-nrd-setup-ns
+- atmel,smc-ncs-wr-setup-ns
+- atmel,smc-nwe-setup-ns
+- atmel,smc-ncs-rd-pulse-ns
+- atmel,smc-nrd-pulse-ns
+- atmel,smc-ncs-wr-pulse-ns
+- atmel,smc-nwe-pulse-ns
+- atmel,smc-nwe-cycle-ns
+- atmel,smc-nrd-cycle-ns
+- atmel,smc-tdf-ns
+
+Example:
+
+       ebi: ebi@10000000 {
+               compatible = "atmel,sama5d3-ebi";
+               #address-cells = <2>;
+               #size-cells = <1>;
+               atmel,smc = <&hsmc>;
+               atmel,matrix = <&matrix>;
+               reg = <0x10000000 0x10000000
+                      0x40000000 0x30000000>;
+               ranges = <0x0 0x0 0x10000000 0x10000000
+                         0x1 0x0 0x40000000 0x10000000
+                         0x2 0x0 0x50000000 0x10000000
+                         0x3 0x0 0x60000000 0x10000000>;
+               clocks = <&mck>;
+
+               pinctrl-names = "default";
+               pinctrl-0 = <&pinctrl_ebi_addr>;
+
+               nor: flash@0,0 {
+                       compatible = "cfi-flash";
+                       #address-cells = <1>;
+                       #size-cells = <1>;
+                       reg = <0x0 0x0 0x1000000>;
+                       bank-width = <2>;
+
+                       atmel,smc-read-mode = "nrd";
+                       atmel,smc-write-mode = "nwe";
+                       atmel,smc-bus-width = <16>;
+                       atmel,smc-ncs-rd-setup-ns = <0>;
+                       atmel,smc-ncs-wr-setup-ns = <0>;
+                       atmel,smc-nwe-setup-ns = <8>;
+                       atmel,smc-nrd-setup-ns = <16>;
+                       atmel,smc-ncs-rd-pulse-ns = <84>;
+                       atmel,smc-ncs-wr-pulse-ns = <84>;
+                       atmel,smc-nrd-pulse-ns = <76>;
+                       atmel,smc-nwe-pulse-ns = <76>;
+                       atmel,smc-nrd-cycle-ns = <107>;
+                       atmel,smc-nwe-cycle-ns = <84>;
+                       atmel,smc-tdf-ns = <16>;
+               };
+       };
+
index 81ddb17..1337123 100644 (file)
@@ -25,6 +25,17 @@ config ATMEL_SDRAMC
          Starting with the at91sam9g45, this controller supports SDR, DDR and
          LP-DDR memories.
 
+config ATMEL_EBI
+       bool "Atmel EBI driver"
+       default y
+       depends on ARCH_AT91 && OF
+       select MFD_SYSCON
+       help
+         Driver for Atmel EBI controller.
+         Used to configure the EBI (external bus interface) when the device-
+         tree is used. This bus supports NANDs, external ethernet controller,
+         SRAMs, ATA devices, etc.
+
 config TI_AEMIF
        tristate "Texas Instruments AEMIF driver"
        depends on (ARCH_DAVINCI || ARCH_KEYSTONE) && OF
index cb0b7a1..b20ae38 100644 (file)
@@ -7,6 +7,7 @@ obj-$(CONFIG_OF)                += of_memory.o
 endif
 obj-$(CONFIG_ARM_PL172_MPMC)   += pl172.o
 obj-$(CONFIG_ATMEL_SDRAMC)     += atmel-sdramc.o
+obj-$(CONFIG_ATMEL_EBI)                += atmel-ebi.o
 obj-$(CONFIG_TI_AEMIF)         += ti-aemif.o
 obj-$(CONFIG_TI_EMIF)          += emif.o
 obj-$(CONFIG_OMAP_GPMC)                += omap-gpmc.o
diff --git a/drivers/memory/atmel-ebi.c b/drivers/memory/atmel-ebi.c
new file mode 100644 (file)
index 0000000..17d9d3f
--- /dev/null
@@ -0,0 +1,771 @@
+/*
+ * EBI driver for Atmel chips
+ * inspired by the fsl weim bus driver
+ *
+ * Copyright (C) 2013 Jean-Jacques Hiblot <jjhiblot@traphandler.com>
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#include <linux/clk.h>
+#include <linux/io.h>
+#include <linux/mfd/syscon.h>
+#include <linux/mfd/syscon/atmel-matrix.h>
+#include <linux/mfd/syscon/atmel-smc.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/regmap.h>
+
+struct at91sam9_smc_timings {
+       u32 ncs_rd_setup_ns;
+       u32 nrd_setup_ns;
+       u32 ncs_wr_setup_ns;
+       u32 nwe_setup_ns;
+       u32 ncs_rd_pulse_ns;
+       u32 nrd_pulse_ns;
+       u32 ncs_wr_pulse_ns;
+       u32 nwe_pulse_ns;
+       u32 nrd_cycle_ns;
+       u32 nwe_cycle_ns;
+       u32 tdf_ns;
+};
+
+struct at91sam9_smc_generic_fields {
+       struct regmap_field *setup;
+       struct regmap_field *pulse;
+       struct regmap_field *cycle;
+       struct regmap_field *mode;
+};
+
+struct at91sam9_ebi_dev_config {
+       struct at91sam9_smc_timings timings;
+       u32 mode;
+};
+
+struct at91_ebi_dev_config {
+       int cs;
+       union {
+               struct at91sam9_ebi_dev_config sam9;
+       };
+};
+
+struct at91_ebi;
+
+struct at91_ebi_dev {
+       struct list_head node;
+       struct at91_ebi *ebi;
+       u32 mode;
+       int numcs;
+       struct at91_ebi_dev_config configs[];
+};
+
+struct at91_ebi_caps {
+       unsigned int available_cs;
+       const struct reg_field *ebi_csa;
+       void (*get_config)(struct at91_ebi_dev *ebid,
+                          struct at91_ebi_dev_config *conf);
+       int (*xlate_config)(struct at91_ebi_dev *ebid,
+                           struct device_node *configs_np,
+                           struct at91_ebi_dev_config *conf);
+       int (*apply_config)(struct at91_ebi_dev *ebid,
+                           struct at91_ebi_dev_config *conf);
+       int (*init)(struct at91_ebi *ebi);
+};
+
+struct at91_ebi {
+       struct clk *clk;
+       struct regmap *smc;
+       struct regmap *matrix;
+
+       struct regmap_field *ebi_csa;
+
+       struct device *dev;
+       const struct at91_ebi_caps *caps;
+       struct list_head devs;
+       union {
+               struct at91sam9_smc_generic_fields sam9;
+       };
+};
+
+static void at91sam9_ebi_get_config(struct at91_ebi_dev *ebid,
+                                   struct at91_ebi_dev_config *conf)
+{
+       struct at91sam9_smc_generic_fields *fields = &ebid->ebi->sam9;
+       unsigned int clk_rate = clk_get_rate(ebid->ebi->clk);
+       struct at91sam9_ebi_dev_config *config = &conf->sam9;
+       struct at91sam9_smc_timings *timings = &config->timings;
+       unsigned int val;
+
+       regmap_fields_read(fields->mode, conf->cs, &val);
+       config->mode = val & ~AT91_SMC_TDF;
+
+       val = (val & AT91_SMC_TDF) >> 16;
+       timings->tdf_ns = clk_rate * val;
+
+       regmap_fields_read(fields->setup, conf->cs, &val);
+       timings->ncs_rd_setup_ns = (val >> 24) & 0x1f;
+       timings->ncs_rd_setup_ns += ((val >> 29) & 0x1) * 128;
+       timings->ncs_rd_setup_ns *= clk_rate;
+       timings->nrd_setup_ns = (val >> 16) & 0x1f;
+       timings->nrd_setup_ns += ((val >> 21) & 0x1) * 128;
+       timings->nrd_setup_ns *= clk_rate;
+       timings->ncs_wr_setup_ns = (val >> 8) & 0x1f;
+       timings->ncs_wr_setup_ns += ((val >> 13) & 0x1) * 128;
+       timings->ncs_wr_setup_ns *= clk_rate;
+       timings->nwe_setup_ns = val & 0x1f;
+       timings->nwe_setup_ns += ((val >> 5) & 0x1) * 128;
+       timings->nwe_setup_ns *= clk_rate;
+
+       regmap_fields_read(fields->pulse, conf->cs, &val);
+       timings->ncs_rd_pulse_ns = (val >> 24) & 0x3f;
+       timings->ncs_rd_pulse_ns += ((val >> 30) & 0x1) * 256;
+       timings->ncs_rd_pulse_ns *= clk_rate;
+       timings->nrd_pulse_ns = (val >> 16) & 0x3f;
+       timings->nrd_pulse_ns += ((val >> 22) & 0x1) * 256;
+       timings->nrd_pulse_ns *= clk_rate;
+       timings->ncs_wr_pulse_ns = (val >> 8) & 0x3f;
+       timings->ncs_wr_pulse_ns += ((val >> 14) & 0x1) * 256;
+       timings->ncs_wr_pulse_ns *= clk_rate;
+       timings->nwe_pulse_ns = val & 0x3f;
+       timings->nwe_pulse_ns += ((val >> 6) & 0x1) * 256;
+       timings->nwe_pulse_ns *= clk_rate;
+
+       regmap_fields_read(fields->cycle, conf->cs, &val);
+       timings->nrd_cycle_ns = (val >> 16) & 0x7f;
+       timings->nrd_cycle_ns += ((val >> 23) & 0x3) * 256;
+       timings->nrd_cycle_ns *= clk_rate;
+       timings->nwe_cycle_ns = val & 0x7f;
+       timings->nwe_cycle_ns += ((val >> 7) & 0x3) * 256;
+       timings->nwe_cycle_ns *= clk_rate;
+}
+
+static int at91_xlate_timing(struct device_node *np, const char *prop,
+                            u32 *val, bool *required)
+{
+       if (!of_property_read_u32(np, prop, val)) {
+               *required = true;
+               return 0;
+       }
+
+       if (*required)
+               return -EINVAL;
+
+       return 0;
+}
+
+static int at91sam9_smc_xslate_timings(struct at91_ebi_dev *ebid,
+                                      struct device_node *np,
+                                      struct at91sam9_smc_timings *timings,
+                                      bool *required)
+{
+       int ret;
+
+       ret = at91_xlate_timing(np, "atmel,smc-ncs-rd-setup-ns",
+                               &timings->ncs_rd_setup_ns, required);
+       if (ret)
+               goto out;
+
+       ret = at91_xlate_timing(np, "atmel,smc-nrd-setup-ns",
+                               &timings->nrd_setup_ns, required);
+       if (ret)
+               goto out;
+
+       ret = at91_xlate_timing(np, "atmel,smc-ncs-wr-setup-ns",
+                               &timings->ncs_wr_setup_ns, required);
+       if (ret)
+               goto out;
+
+       ret = at91_xlate_timing(np, "atmel,smc-nwe-setup-ns",
+                               &timings->nwe_setup_ns, required);
+       if (ret)
+               goto out;
+
+       ret = at91_xlate_timing(np, "atmel,smc-ncs-rd-pulse-ns",
+                               &timings->ncs_rd_pulse_ns, required);
+       if (ret)
+               goto out;
+
+       ret = at91_xlate_timing(np, "atmel,smc-nrd-pulse-ns",
+                               &timings->nrd_pulse_ns, required);
+       if (ret)
+               goto out;
+
+       ret = at91_xlate_timing(np, "atmel,smc-ncs-wr-pulse-ns",
+                               &timings->ncs_wr_pulse_ns, required);
+       if (ret)
+               goto out;
+
+       ret = at91_xlate_timing(np, "atmel,smc-nwe-pulse-ns",
+                               &timings->nwe_pulse_ns, required);
+       if (ret)
+               goto out;
+
+       ret = at91_xlate_timing(np, "atmel,smc-nwe-cycle-ns",
+                               &timings->nwe_cycle_ns, required);
+       if (ret)
+               goto out;
+
+       ret = at91_xlate_timing(np, "atmel,smc-nrd-cycle-ns",
+                               &timings->nrd_cycle_ns, required);
+       if (ret)
+               goto out;
+
+       ret = at91_xlate_timing(np, "atmel,smc-tdf-ns",
+                               &timings->tdf_ns, required);
+
+out:
+       if (ret)
+               dev_err(ebid->ebi->dev,
+                       "missing or invalid timings definition in %s",
+                       np->full_name);
+
+       return ret;
+}
+
+static int at91sam9_ebi_xslate_config(struct at91_ebi_dev *ebid,
+                                     struct device_node *np,
+                                     struct at91_ebi_dev_config *conf)
+{
+       struct at91sam9_ebi_dev_config *config = &conf->sam9;
+       bool required = false;
+       const char *tmp_str;
+       u32 tmp;
+       int ret;
+
+       ret = of_property_read_u32(np, "atmel,smc-bus-width", &tmp);
+       if (!ret) {
+               switch (tmp) {
+               case 8:
+                       config->mode |= AT91_SMC_DBW_8;
+                       break;
+
+               case 16:
+                       config->mode |= AT91_SMC_DBW_16;
+                       break;
+
+               case 32:
+                       config->mode |= AT91_SMC_DBW_32;
+                       break;
+
+               default:
+                       return -EINVAL;
+               }
+
+               required = true;
+       }
+
+       if (of_property_read_bool(np, "atmel,smc-tdf-optimized")) {
+               config->mode |= AT91_SMC_TDFMODE_OPTIMIZED;
+               required = true;
+       }
+
+       tmp_str = NULL;
+       of_property_read_string(np, "atmel,smc-byte-access-type", &tmp_str);
+       if (tmp_str && !strcmp(tmp_str, "write")) {
+               config->mode |= AT91_SMC_BAT_WRITE;
+               required = true;
+       }
+
+       tmp_str = NULL;
+       of_property_read_string(np, "atmel,smc-read-mode", &tmp_str);
+       if (tmp_str && !strcmp(tmp_str, "nrd")) {
+               config->mode |= AT91_SMC_READMODE_NRD;
+               required = true;
+       }
+
+       tmp_str = NULL;
+       of_property_read_string(np, "atmel,smc-write-mode", &tmp_str);
+       if (tmp_str && !strcmp(tmp_str, "nwe")) {
+               config->mode |= AT91_SMC_WRITEMODE_NWE;
+               required = true;
+       }
+
+       tmp_str = NULL;
+       of_property_read_string(np, "atmel,smc-exnw-mode", &tmp_str);
+       if (tmp_str) {
+               if (!strcmp(tmp_str, "frozen"))
+                       config->mode |= AT91_SMC_EXNWMODE_FROZEN;
+               else if (!strcmp(tmp_str, "ready"))
+                       config->mode |= AT91_SMC_EXNWMODE_READY;
+               else if (strcmp(tmp_str, "disabled"))
+                       return -EINVAL;
+
+               required = true;
+       }
+
+       ret = of_property_read_u32(np, "atmel,smc-page-mode", &tmp);
+       if (!ret) {
+               switch (tmp) {
+               case 4:
+                       config->mode |= AT91_SMC_PS_4;
+                       break;
+
+               case 8:
+                       config->mode |= AT91_SMC_PS_8;
+                       break;
+
+               case 16:
+                       config->mode |= AT91_SMC_PS_16;
+                       break;
+
+               case 32:
+                       config->mode |= AT91_SMC_PS_32;
+                       break;
+
+               default:
+                       return -EINVAL;
+               }
+
+               config->mode |= AT91_SMC_PMEN;
+               required = true;
+       }
+
+       ret = at91sam9_smc_xslate_timings(ebid, np, &config->timings,
+                                         &required);
+       if (ret)
+               return ret;
+
+       return required;
+}
+
+static int at91sam9_ebi_apply_config(struct at91_ebi_dev *ebid,
+                                    struct at91_ebi_dev_config *conf)
+{
+       unsigned int clk_rate = clk_get_rate(ebid->ebi->clk);
+       struct at91sam9_ebi_dev_config *config = &conf->sam9;
+       struct at91sam9_smc_timings *timings = &config->timings;
+       struct at91sam9_smc_generic_fields *fields = &ebid->ebi->sam9;
+       u32 coded_val;
+       u32 val;
+
+       coded_val = at91sam9_smc_setup_ns_to_cycles(clk_rate,
+                                                   timings->ncs_rd_setup_ns);
+       val = AT91SAM9_SMC_NCS_NRDSETUP(coded_val);
+       coded_val = at91sam9_smc_setup_ns_to_cycles(clk_rate,
+                                                   timings->nrd_setup_ns);
+       val |= AT91SAM9_SMC_NRDSETUP(coded_val);
+       coded_val = at91sam9_smc_setup_ns_to_cycles(clk_rate,
+                                                   timings->ncs_wr_setup_ns);
+       val |= AT91SAM9_SMC_NCS_WRSETUP(coded_val);
+       coded_val = at91sam9_smc_setup_ns_to_cycles(clk_rate,
+                                                   timings->nwe_setup_ns);
+       val |= AT91SAM9_SMC_NWESETUP(coded_val);
+       regmap_fields_write(fields->setup, conf->cs, val);
+
+       coded_val = at91sam9_smc_pulse_ns_to_cycles(clk_rate,
+                                                   timings->ncs_rd_pulse_ns);
+       val = AT91SAM9_SMC_NCS_NRDPULSE(coded_val);
+       coded_val = at91sam9_smc_pulse_ns_to_cycles(clk_rate,
+                                                   timings->nrd_pulse_ns);
+       val |= AT91SAM9_SMC_NRDPULSE(coded_val);
+       coded_val = at91sam9_smc_pulse_ns_to_cycles(clk_rate,
+                                                   timings->ncs_wr_pulse_ns);
+       val |= AT91SAM9_SMC_NCS_WRPULSE(coded_val);
+       coded_val = at91sam9_smc_pulse_ns_to_cycles(clk_rate,
+                                                   timings->nwe_pulse_ns);
+       val |= AT91SAM9_SMC_NWEPULSE(coded_val);
+       regmap_fields_write(fields->pulse, conf->cs, val);
+
+       coded_val = at91sam9_smc_cycle_ns_to_cycles(clk_rate,
+                                                   timings->nrd_cycle_ns);
+       val = AT91SAM9_SMC_NRDCYCLE(coded_val);
+       coded_val = at91sam9_smc_cycle_ns_to_cycles(clk_rate,
+                                                   timings->nwe_cycle_ns);
+       val |= AT91SAM9_SMC_NWECYCLE(coded_val);
+       regmap_fields_write(fields->cycle, conf->cs, val);
+
+       val = DIV_ROUND_UP(timings->tdf_ns, clk_rate);
+       if (val > AT91_SMC_TDF_MAX)
+               val = AT91_SMC_TDF_MAX;
+       regmap_fields_write(fields->mode, conf->cs,
+                           config->mode | AT91_SMC_TDF_(val));
+
+       return 0;
+}
+
+static int at91sam9_ebi_init(struct at91_ebi *ebi)
+{
+       struct at91sam9_smc_generic_fields *fields = &ebi->sam9;
+       struct reg_field field = REG_FIELD(0, 0, 31);
+
+       field.id_size = fls(ebi->caps->available_cs);
+       field.id_offset = AT91SAM9_SMC_GENERIC_BLK_SZ;
+
+       field.reg = AT91SAM9_SMC_SETUP(AT91SAM9_SMC_GENERIC);
+       fields->setup = devm_regmap_field_alloc(ebi->dev, ebi->smc, field);
+       if (IS_ERR(fields->setup))
+               return PTR_ERR(fields->setup);
+
+       field.reg = AT91SAM9_SMC_PULSE(AT91SAM9_SMC_GENERIC);
+       fields->pulse = devm_regmap_field_alloc(ebi->dev, ebi->smc, field);
+       if (IS_ERR(fields->pulse))
+               return PTR_ERR(fields->pulse);
+
+       field.reg = AT91SAM9_SMC_CYCLE(AT91SAM9_SMC_GENERIC);
+       fields->cycle = devm_regmap_field_alloc(ebi->dev, ebi->smc, field);
+       if (IS_ERR(fields->cycle))
+               return PTR_ERR(fields->cycle);
+
+       field.reg = AT91SAM9_SMC_MODE(AT91SAM9_SMC_GENERIC);
+       fields->mode = devm_regmap_field_alloc(ebi->dev, ebi->smc, field);
+       if (IS_ERR(fields->mode))
+               return PTR_ERR(fields->mode);
+
+       return 0;
+}
+
+static int sama5d3_ebi_init(struct at91_ebi *ebi)
+{
+       struct at91sam9_smc_generic_fields *fields = &ebi->sam9;
+       struct reg_field field = REG_FIELD(0, 0, 31);
+
+       field.id_size = fls(ebi->caps->available_cs);
+       field.id_offset = SAMA5_SMC_GENERIC_BLK_SZ;
+
+       field.reg = AT91SAM9_SMC_SETUP(SAMA5_SMC_GENERIC);
+       fields->setup = devm_regmap_field_alloc(ebi->dev, ebi->smc, field);
+       if (IS_ERR(fields->setup))
+               return PTR_ERR(fields->setup);
+
+       field.reg = AT91SAM9_SMC_PULSE(SAMA5_SMC_GENERIC);
+       fields->pulse = devm_regmap_field_alloc(ebi->dev, ebi->smc, field);
+       if (IS_ERR(fields->pulse))
+               return PTR_ERR(fields->pulse);
+
+       field.reg = AT91SAM9_SMC_CYCLE(SAMA5_SMC_GENERIC);
+       fields->cycle = devm_regmap_field_alloc(ebi->dev, ebi->smc, field);
+       if (IS_ERR(fields->cycle))
+               return PTR_ERR(fields->cycle);
+
+       field.reg = SAMA5_SMC_MODE(SAMA5_SMC_GENERIC);
+       fields->mode = devm_regmap_field_alloc(ebi->dev, ebi->smc, field);
+       if (IS_ERR(fields->mode))
+               return PTR_ERR(fields->mode);
+
+       return 0;
+}
+
+static int at91_ebi_dev_setup(struct at91_ebi *ebi, struct device_node *np,
+                             int reg_cells)
+{
+       const struct at91_ebi_caps *caps = ebi->caps;
+       struct at91_ebi_dev_config conf = { };
+       struct device *dev = ebi->dev;
+       struct at91_ebi_dev *ebid;
+       int ret, numcs = 0, i;
+       bool apply = false;
+
+       numcs = of_property_count_elems_of_size(np, "reg",
+                                               reg_cells * sizeof(u32));
+       if (numcs <= 0) {
+               dev_err(dev, "invalid reg property in %s\n", np->full_name);
+               return -EINVAL;
+       }
+
+       ebid = devm_kzalloc(ebi->dev,
+                           sizeof(*ebid) + (numcs * sizeof(*ebid->configs)),
+                           GFP_KERNEL);
+       if (!ebid)
+               return -ENOMEM;
+
+       ebid->ebi = ebi;
+
+       ret = caps->xlate_config(ebid, np, &conf);
+       if (ret < 0)
+               return ret;
+       else if (ret)
+               apply = true;
+
+       for (i = 0; i < numcs; i++) {
+               u32 cs;
+
+               ret = of_property_read_u32_index(np, "reg", i * reg_cells,
+                                                &cs);
+               if (ret)
+                       return ret;
+
+               if (cs > AT91_MATRIX_EBI_NUM_CS ||
+                   !(ebi->caps->available_cs & BIT(cs))) {
+                       dev_err(dev, "invalid reg property in %s\n",
+                               np->full_name);
+                       return -EINVAL;
+               }
+
+               ebid->configs[i].cs = cs;
+
+               if (apply) {
+                       conf.cs = cs;
+                       ret = caps->apply_config(ebid, &conf);
+                       if (ret)
+                               return ret;
+               }
+
+               caps->get_config(ebid, &ebid->configs[i]);
+
+               /*
+                * Attach the EBI device to the generic SMC logic if at least
+                * one "atmel,smc-" property is present.
+                */
+               if (ebi->ebi_csa && ret)
+                       regmap_field_update_bits(ebi->ebi_csa,
+                                                BIT(cs), 0);
+       }
+
+       list_add_tail(&ebid->node, &ebi->devs);
+
+       return 0;
+}
+
+static const struct reg_field at91sam9260_ebi_csa =
+                               REG_FIELD(AT91SAM9260_MATRIX_EBICSA, 0,
+                                         AT91_MATRIX_EBI_NUM_CS - 1);
+
+static const struct at91_ebi_caps at91sam9260_ebi_caps = {
+       .available_cs = 0xff,
+       .ebi_csa = &at91sam9260_ebi_csa,
+       .get_config = at91sam9_ebi_get_config,
+       .xlate_config = at91sam9_ebi_xslate_config,
+       .apply_config = at91sam9_ebi_apply_config,
+       .init = at91sam9_ebi_init,
+};
+
+static const struct reg_field at91sam9261_ebi_csa =
+                               REG_FIELD(AT91SAM9261_MATRIX_EBICSA, 0,
+                                         AT91_MATRIX_EBI_NUM_CS - 1);
+
+static const struct at91_ebi_caps at91sam9261_ebi_caps = {
+       .available_cs = 0xff,
+       .ebi_csa = &at91sam9261_ebi_csa,
+       .get_config = at91sam9_ebi_get_config,
+       .xlate_config = at91sam9_ebi_xslate_config,
+       .apply_config = at91sam9_ebi_apply_config,
+       .init = at91sam9_ebi_init,
+};
+
+static const struct reg_field at91sam9263_ebi0_csa =
+                               REG_FIELD(AT91SAM9263_MATRIX_EBI0CSA, 0,
+                                         AT91_MATRIX_EBI_NUM_CS - 1);
+
+static const struct at91_ebi_caps at91sam9263_ebi0_caps = {
+       .available_cs = 0x3f,
+       .ebi_csa = &at91sam9263_ebi0_csa,
+       .get_config = at91sam9_ebi_get_config,
+       .xlate_config = at91sam9_ebi_xslate_config,
+       .apply_config = at91sam9_ebi_apply_config,
+       .init = at91sam9_ebi_init,
+};
+
+static const struct reg_field at91sam9263_ebi1_csa =
+                               REG_FIELD(AT91SAM9263_MATRIX_EBI1CSA, 0,
+                                         AT91_MATRIX_EBI_NUM_CS - 1);
+
+static const struct at91_ebi_caps at91sam9263_ebi1_caps = {
+       .available_cs = 0x7,
+       .ebi_csa = &at91sam9263_ebi1_csa,
+       .get_config = at91sam9_ebi_get_config,
+       .xlate_config = at91sam9_ebi_xslate_config,
+       .apply_config = at91sam9_ebi_apply_config,
+       .init = at91sam9_ebi_init,
+};
+
+static const struct reg_field at91sam9rl_ebi_csa =
+                               REG_FIELD(AT91SAM9RL_MATRIX_EBICSA, 0,
+                                         AT91_MATRIX_EBI_NUM_CS - 1);
+
+static const struct at91_ebi_caps at91sam9rl_ebi_caps = {
+       .available_cs = 0x3f,
+       .ebi_csa = &at91sam9rl_ebi_csa,
+       .get_config = at91sam9_ebi_get_config,
+       .xlate_config = at91sam9_ebi_xslate_config,
+       .apply_config = at91sam9_ebi_apply_config,
+       .init = at91sam9_ebi_init,
+};
+
+static const struct reg_field at91sam9g45_ebi_csa =
+                               REG_FIELD(AT91SAM9G45_MATRIX_EBICSA, 0,
+                                         AT91_MATRIX_EBI_NUM_CS - 1);
+
+static const struct at91_ebi_caps at91sam9g45_ebi_caps = {
+       .available_cs = 0x3f,
+       .ebi_csa = &at91sam9g45_ebi_csa,
+       .get_config = at91sam9_ebi_get_config,
+       .xlate_config = at91sam9_ebi_xslate_config,
+       .apply_config = at91sam9_ebi_apply_config,
+       .init = at91sam9_ebi_init,
+};
+
+static const struct at91_ebi_caps at91sam9x5_ebi_caps = {
+       .available_cs = 0x3f,
+       .ebi_csa = &at91sam9263_ebi0_csa,
+       .get_config = at91sam9_ebi_get_config,
+       .xlate_config = at91sam9_ebi_xslate_config,
+       .apply_config = at91sam9_ebi_apply_config,
+       .init = at91sam9_ebi_init,
+};
+
+static const struct at91_ebi_caps sama5d3_ebi_caps = {
+       .available_cs = 0xf,
+       .get_config = at91sam9_ebi_get_config,
+       .xlate_config = at91sam9_ebi_xslate_config,
+       .apply_config = at91sam9_ebi_apply_config,
+       .init = sama5d3_ebi_init,
+};
+
+static const struct of_device_id at91_ebi_id_table[] = {
+       {
+               .compatible = "atmel,at91sam9260-ebi",
+               .data = &at91sam9260_ebi_caps,
+       },
+       {
+               .compatible = "atmel,at91sam9261-ebi",
+               .data = &at91sam9261_ebi_caps,
+       },
+       {
+               .compatible = "atmel,at91sam9263-ebi0",
+               .data = &at91sam9263_ebi0_caps,
+       },
+       {
+               .compatible = "atmel,at91sam9263-ebi1",
+               .data = &at91sam9263_ebi1_caps,
+       },
+       {
+               .compatible = "atmel,at91sam9rl-ebi",
+               .data = &at91sam9rl_ebi_caps,
+       },
+       {
+               .compatible = "atmel,at91sam9g45-ebi",
+               .data = &at91sam9g45_ebi_caps,
+       },
+       {
+               .compatible = "atmel,at91sam9x5-ebi",
+               .data = &at91sam9x5_ebi_caps,
+       },
+       {
+               .compatible = "atmel,sama5d3-ebi",
+               .data = &sama5d3_ebi_caps,
+       },
+       { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, at91_ebi_id_table);
+
+static int at91_ebi_dev_disable(struct at91_ebi *ebi, struct device_node *np)
+{
+       struct device *dev = ebi->dev;
+       struct property *newprop;
+
+       newprop = devm_kzalloc(dev, sizeof(*newprop), GFP_KERNEL);
+       if (!newprop)
+               return -ENOMEM;
+
+       newprop->name = devm_kstrdup(dev, "status", GFP_KERNEL);
+       if (!newprop->name)
+               return -ENOMEM;
+
+       newprop->value = devm_kstrdup(dev, "disabled", GFP_KERNEL);
+       if (!newprop->name)
+               return -ENOMEM;
+
+       newprop->length = sizeof("disabled");
+
+       return of_update_property(np, newprop);
+}
+
+static int at91_ebi_probe(struct platform_device *pdev)
+{
+       struct device *dev = &pdev->dev;
+       struct device_node *child, *np = dev->of_node;
+       const struct of_device_id *match;
+       struct at91_ebi *ebi;
+       int ret, reg_cells;
+       struct clk *clk;
+       u32 val;
+
+       match = of_match_device(at91_ebi_id_table, dev);
+       if (!match || !match->data)
+               return -EINVAL;
+
+       ebi = devm_kzalloc(dev, sizeof(*ebi), GFP_KERNEL);
+       if (!ebi)
+               return -ENOMEM;
+
+       INIT_LIST_HEAD(&ebi->devs);
+       ebi->caps = match->data;
+       ebi->dev = dev;
+
+       clk = devm_clk_get(dev, NULL);
+       if (IS_ERR(clk))
+               return PTR_ERR(clk);
+
+       ebi->clk = clk;
+
+       ebi->smc = syscon_regmap_lookup_by_phandle(np, "atmel,smc");
+       if (IS_ERR(ebi->smc))
+               return PTR_ERR(ebi->smc);
+
+       /*
+        * The sama5d3 does not provide an EBICSA register and thus does need
+        * to access the matrix registers.
+        */
+       if (ebi->caps->ebi_csa) {
+               ebi->matrix =
+                       syscon_regmap_lookup_by_phandle(np, "atmel,matrix");
+               if (IS_ERR(ebi->matrix))
+                       return PTR_ERR(ebi->matrix);
+
+               ebi->ebi_csa = regmap_field_alloc(ebi->matrix,
+                                                 *ebi->caps->ebi_csa);
+               if (IS_ERR(ebi->ebi_csa))
+                       return PTR_ERR(ebi->ebi_csa);
+       }
+
+       ret = ebi->caps->init(ebi);
+       if (ret)
+               return ret;
+
+       ret = of_property_read_u32(np, "#address-cells", &val);
+       if (ret) {
+               dev_err(dev, "missing #address-cells property\n");
+               return ret;
+       }
+
+       reg_cells = val;
+
+       ret = of_property_read_u32(np, "#size-cells", &val);
+       if (ret) {
+               dev_err(dev, "missing #address-cells property\n");
+               return ret;
+       }
+
+       reg_cells += val;
+
+       for_each_available_child_of_node(np, child) {
+               if (!of_find_property(child, "reg", NULL))
+                       continue;
+
+               ret = at91_ebi_dev_setup(ebi, child, reg_cells);
+               if (ret) {
+                       dev_err(dev, "failed to configure EBI bus for %s, disabling the device",
+                               child->full_name);
+
+                       ret = at91_ebi_dev_disable(ebi, child);
+                       if (ret)
+                               return ret;
+               }
+       }
+
+       return of_platform_populate(np, NULL, NULL, dev);
+}
+
+static struct platform_driver at91_ebi_driver = {
+       .driver = {
+               .name = "atmel-ebi",
+               .of_match_table = at91_ebi_id_table,
+       },
+};
+module_platform_driver_probe(at91_ebi_driver, at91_ebi_probe);
+
+MODULE_AUTHOR("Jean-Jacques Hiblot <jjhiblot@traphandler.com>");
+MODULE_DESCRIPTION("Atmel EBI driver");
+MODULE_LICENSE("GPL");