@@ -200,6 +200,17 @@ config DA8XX_MSTPRI
configuration. Allows to adjust the priorities of all master
peripherals.
+config STM32_FMC2_EBI
+ tristate "Support for FMC2 External Bus Interface on STM32MP SoCs"
+ depends on MACH_STM32MP157 || COMPILE_TEST
+ select REGMAP
+ select MFD_STM32_FMC2
+ help
+ Select this option to enable the STM32 FMC2 External Bus Interface
+ controller. This driver configures the transactions with external
+ devices (like SRAM, ethernet adapters, FPGAs, LCD displays, ...) on
+ SOCs containing the FMC2 External Bus Interface.
+
source "drivers/bus/fsl-mc/Kconfig"
endmenu
@@ -25,6 +25,7 @@ obj-$(CONFIG_QCOM_EBI2) += qcom-ebi2.o
obj-$(CONFIG_SUN50I_DE2_BUS) += sun50i-de2.o
obj-$(CONFIG_SUNXI_RSB) += sunxi-rsb.o
obj-$(CONFIG_SIMPLE_PM_BUS) += simple-pm-bus.o
+obj-$(CONFIG_STM32_FMC2_EBI) += stm32-fmc2-ebi.o
obj-$(CONFIG_TEGRA_ACONNECT) += tegra-aconnect.o
obj-$(CONFIG_TEGRA_GMI) += tegra-gmi.o
obj-$(CONFIG_TI_PWMSS) += ti-pwmss.o
new file mode 100644
@@ -0,0 +1,1093 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) STMicroelectronics 2020
+ */
+
+#include <linux/mfd/stm32-fmc2.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+
+#define FMC2_MAX_EBI_CE 4
+
+#define FMC2_BCR_CPSIZE_0 0x0
+#define FMC2_BCR_CPSIZE_128 0x1
+#define FMC2_BCR_CPSIZE_256 0x2
+#define FMC2_BCR_CPSIZE_512 0x3
+#define FMC2_BCR_CPSIZE_1024 0x4
+
+#define FMC2_BCR_MWID_8 0x0
+#define FMC2_BCR_MWID_16 0x1
+
+#define FMC2_BCR_MTYP_SRAM 0x0
+#define FMC2_BCR_MTYP_PSRAM 0x1
+#define FMC2_BCR_MTYP_NOR 0x2
+
+#define FMC2_BXTR_EXTMOD_A 0x0
+#define FMC2_BXTR_EXTMOD_B 0x1
+#define FMC2_BXTR_EXTMOD_C 0x2
+#define FMC2_BXTR_EXTMOD_D 0x3
+
+#define FMC2_BCR_NBLSET_MAX 0x3
+#define FMC2_BXTR_ADDSET_MAX 0xf
+#define FMC2_BXTR_ADDHLD_MAX 0xf
+#define FMC2_BXTR_DATAST_MAX 0xff
+#define FMC2_BXTR_BUSTURN_MAX 0xf
+#define FMC2_BXTR_DATAHLD_MAX 0x3
+#define FMC2_BTR_CLKDIV_MAX 0xf
+#define FMC2_BTR_DATLAT_MAX 0xf
+#define FMC2_PCSCNTR_CSCOUNT_MAX 0xff
+
+enum stm32_fmc2_ebi_register_type {
+ FMC2_REG_BCR = 1,
+ FMC2_REG_BTR,
+ FMC2_REG_BWTR,
+ FMC2_REG_PCSCNTR
+};
+
+enum stm32_fmc2_ebi_transaction_type {
+ FMC2_ASYNC_MODE_1_SRAM = 0,
+ FMC2_ASYNC_MODE_1_PSRAM,
+ FMC2_ASYNC_MODE_A_SRAM,
+ FMC2_ASYNC_MODE_A_PSRAM,
+ FMC2_ASYNC_MODE_2_NOR,
+ FMC2_ASYNC_MODE_B_NOR,
+ FMC2_ASYNC_MODE_C_NOR,
+ FMC2_ASYNC_MODE_D_NOR,
+ FMC2_SYNC_READ_SYNC_WRITE_PSRAM,
+ FMC2_SYNC_READ_ASYNC_WRITE_PSRAM,
+ FMC2_SYNC_READ_SYNC_WRITE_NOR,
+ FMC2_SYNC_READ_ASYNC_WRITE_NOR
+};
+
+enum stm32_fmc2_ebi_buswidth {
+ FMC2_BUSWIDTH_8 = 8,
+ FMC2_BUSWIDTH_16 = 16
+};
+
+enum stm32_fmc2_ebi_cpsize {
+ FMC2_CPSIZE_0 = 0,
+ FMC2_CPSIZE_128 = 128,
+ FMC2_CPSIZE_256 = 256,
+ FMC2_CPSIZE_512 = 512,
+ FMC2_CPSIZE_1024 = 1024
+};
+
+struct stm32_fmc2_ebi {
+ u32 bcr[FMC2_MAX_EBI_CE];
+ u32 btr[FMC2_MAX_EBI_CE];
+ u32 bwtr[FMC2_MAX_EBI_CE];
+ u32 pcscntr;
+ u8 cs_assigned;
+};
+
+/*
+ * struct stm32_fmc2_prop - STM32 FMC2 EBI property
+ * @name: the device tree binding name of the property
+ * @bprop: indicate that it is a boolean property
+ * @mprop: indicate that it is a mandatory property
+ * @reg_type: the register that have to be modified
+ * @reg_mask: the bit that have to be modified in the selected register
+ * in case of it is a boolean property
+ * @reset_val: the default value that have to be set in case the property
+ * has not been defined in the device tree
+ * @check: this callback ckecks that the property is compliant with the
+ * transaction type selected
+ * @calculate: this callback is called to calculate for exemple a timing
+ * set in ns in the device tree in clock cycles
+ * @set: this callback applies the values in the registers
+ */
+struct stm32_fmc2_prop {
+ const char *name;
+ bool bprop;
+ bool mprop;
+ int reg_type;
+ u32 reg_mask;
+ u32 reset_val;
+ int (*check)(struct stm32_fmc2 *fmc2,
+ const struct stm32_fmc2_prop *prop, int cs);
+ u32 (*calculate)(struct stm32_fmc2 *fmc2, u32 setup);
+ int (*set)(struct stm32_fmc2 *fmc2, const struct stm32_fmc2_prop *prop,
+ int cs, u32 setup);
+};
+
+static int stm32_fmc2_ebi_check_mux(struct stm32_fmc2 *fmc2,
+ const struct stm32_fmc2_prop *prop,
+ int cs)
+{
+ u32 bcr;
+
+ regmap_read(fmc2->regmap, FMC2_BCR(cs), &bcr);
+
+ if (bcr & FMC2_BCR_MTYP)
+ return 0;
+
+ return -EINVAL;
+}
+
+static int stm32_fmc2_ebi_check_waitcfg(struct stm32_fmc2 *fmc2,
+ const struct stm32_fmc2_prop *prop,
+ int cs)
+{
+ u32 bcr, val = FIELD_PREP(FMC2_BCR_MTYP, FMC2_BCR_MTYP_NOR);
+
+ regmap_read(fmc2->regmap, FMC2_BCR(cs), &bcr);
+
+ if ((bcr & FMC2_BCR_MTYP) == val && bcr & FMC2_BCR_BURSTEN)
+ return 0;
+
+ return -EINVAL;
+}
+
+static int stm32_fmc2_ebi_check_sync_trans(struct stm32_fmc2 *fmc2,
+ const struct stm32_fmc2_prop *prop,
+ int cs)
+{
+ u32 bcr;
+
+ regmap_read(fmc2->regmap, FMC2_BCR(cs), &bcr);
+
+ if (bcr & FMC2_BCR_BURSTEN)
+ return 0;
+
+ return -EINVAL;
+}
+
+static int stm32_fmc2_ebi_check_async_trans(struct stm32_fmc2 *fmc2,
+ const struct stm32_fmc2_prop *prop,
+ int cs)
+{
+ u32 bcr;
+
+ regmap_read(fmc2->regmap, FMC2_BCR(cs), &bcr);
+
+ if (!(bcr & FMC2_BCR_BURSTEN) || !(bcr & FMC2_BCR_CBURSTRW))
+ return 0;
+
+ return -EINVAL;
+}
+
+static int stm32_fmc2_ebi_check_cpsize(struct stm32_fmc2 *fmc2,
+ const struct stm32_fmc2_prop *prop,
+ int cs)
+{
+ u32 bcr, val = FIELD_PREP(FMC2_BCR_MTYP, FMC2_BCR_MTYP_PSRAM);
+
+ regmap_read(fmc2->regmap, FMC2_BCR(cs), &bcr);
+
+ if ((bcr & FMC2_BCR_MTYP) == val && bcr & FMC2_BCR_BURSTEN)
+ return 0;
+
+ return -EINVAL;
+}
+
+static int stm32_fmc2_ebi_check_address_hold(struct stm32_fmc2 *fmc2,
+ const struct stm32_fmc2_prop *prop,
+ int cs)
+{
+ u32 bcr, bxtr, val = FIELD_PREP(FMC2_BXTR_ACCMOD, FMC2_BXTR_EXTMOD_D);
+
+ regmap_read(fmc2->regmap, FMC2_BCR(cs), &bcr);
+ if (prop->reg_type == FMC2_REG_BWTR)
+ regmap_read(fmc2->regmap, FMC2_BWTR(cs), &bxtr);
+ else
+ regmap_read(fmc2->regmap, FMC2_BTR(cs), &bxtr);
+
+ if ((!(bcr & FMC2_BCR_BURSTEN) || !(bcr & FMC2_BCR_CBURSTRW)) &&
+ ((bxtr & FMC2_BXTR_ACCMOD) == val || bcr & FMC2_BCR_MUXEN))
+ return 0;
+
+ return -EINVAL;
+}
+
+static int stm32_fmc2_ebi_check_clk_period(struct stm32_fmc2 *fmc2,
+ const struct stm32_fmc2_prop *prop,
+ int cs)
+{
+ u32 bcr, bcr1;
+
+ regmap_read(fmc2->regmap, FMC2_BCR(cs), &bcr);
+ if (cs)
+ regmap_read(fmc2->regmap, FMC2_BCR(0), &bcr1);
+ else
+ bcr1 = bcr;
+
+ if (bcr & FMC2_BCR_BURSTEN && (!cs || !(bcr1 & FMC2_BCR1_CCLKEN)))
+ return 0;
+
+ return -EINVAL;
+}
+
+static int stm32_fmc2_ebi_check_cclk(struct stm32_fmc2 *fmc2,
+ const struct stm32_fmc2_prop *prop,
+ int cs)
+{
+ if (cs)
+ return -EINVAL;
+
+ return stm32_fmc2_ebi_check_sync_trans(fmc2, prop, cs);
+}
+
+static u32 stm32_fmc2_ebi_timing_ns_to_clock_cycles(struct stm32_fmc2 *fmc2,
+ u32 setup)
+{
+ unsigned long hclk = clk_get_rate(fmc2->clk);
+ unsigned long hclkp = NSEC_PER_SEC / (hclk / 1000);
+
+ return DIV_ROUND_UP(setup * 1000, hclkp);
+}
+
+static int stm32_fmc2_ebi_get_reg(int reg_type, int cs, u32 *reg)
+{
+ switch (reg_type) {
+ case FMC2_REG_BCR:
+ *reg = FMC2_BCR(cs);
+ break;
+ case FMC2_REG_BTR:
+ *reg = FMC2_BTR(cs);
+ break;
+ case FMC2_REG_BWTR:
+ *reg = FMC2_BWTR(cs);
+ break;
+ case FMC2_REG_PCSCNTR:
+ *reg = FMC2_PCSCNTR;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static int stm32_fmc2_ebi_set_bit_field(struct stm32_fmc2 *fmc2,
+ const struct stm32_fmc2_prop *prop,
+ int cs, u32 setup)
+{
+ u32 reg;
+ int ret;
+
+ ret = stm32_fmc2_ebi_get_reg(prop->reg_type, cs, ®);
+ if (ret)
+ return ret;
+
+ regmap_update_bits(fmc2->regmap, reg, prop->reg_mask,
+ setup ? prop->reg_mask : 0);
+
+ return 0;
+}
+
+static int stm32_fmc2_ebi_set_trans_type(struct stm32_fmc2 *fmc2,
+ const struct stm32_fmc2_prop *prop,
+ int cs, u32 setup)
+{
+ u32 bcr_mask, bcr = FMC2_BCR_WREN;
+ u32 btr_mask, btr = 0;
+ u32 bwtr_mask, bwtr = 0;
+
+ bwtr_mask = FMC2_BXTR_ACCMOD;
+ btr_mask = FMC2_BXTR_ACCMOD;
+ bcr_mask = FMC2_BCR_MUXEN | FMC2_BCR_MTYP | FMC2_BCR_FACCEN |
+ FMC2_BCR_WREN | FMC2_BCR_WAITEN | FMC2_BCR_BURSTEN |
+ FMC2_BCR_EXTMOD | FMC2_BCR_CBURSTRW;
+
+ switch (setup) {
+ case FMC2_ASYNC_MODE_1_SRAM:
+ bcr |= FIELD_PREP(FMC2_BCR_MTYP, FMC2_BCR_MTYP_SRAM);
+ /*
+ * MUXEN = 0, MTYP = 0, FACCEN = 0, BURSTEN = 0, WAITEN = 0,
+ * WREN = 1, EXTMOD = 0, CBURSTRW = 0, ACCMOD = 0
+ */
+ break;
+ case FMC2_ASYNC_MODE_1_PSRAM:
+ /*
+ * MUXEN = 0, MTYP = 1, FACCEN = 0, BURSTEN = 0, WAITEN = 0,
+ * WREN = 1, EXTMOD = 0, CBURSTRW = 0, ACCMOD = 0
+ */
+ bcr |= FIELD_PREP(FMC2_BCR_MTYP, FMC2_BCR_MTYP_PSRAM);
+ break;
+ case FMC2_ASYNC_MODE_A_SRAM:
+ /*
+ * MUXEN = 0, MTYP = 0, FACCEN = 0, BURSTEN = 0, WAITEN = 0,
+ * WREN = 1, EXTMOD = 1, CBURSTRW = 0, ACCMOD = 0
+ */
+ bcr |= FIELD_PREP(FMC2_BCR_MTYP, FMC2_BCR_MTYP_SRAM);
+ bcr |= FMC2_BCR_EXTMOD;
+ btr |= FIELD_PREP(FMC2_BXTR_ACCMOD, FMC2_BXTR_EXTMOD_A);
+ bwtr |= FIELD_PREP(FMC2_BXTR_ACCMOD, FMC2_BXTR_EXTMOD_A);
+ break;
+ case FMC2_ASYNC_MODE_A_PSRAM:
+ /*
+ * MUXEN = 0, MTYP = 1, FACCEN = 0, BURSTEN = 0, WAITEN = 0,
+ * WREN = 1, EXTMOD = 1, CBURSTRW = 0, ACCMOD = 0
+ */
+ bcr |= FIELD_PREP(FMC2_BCR_MTYP, FMC2_BCR_MTYP_PSRAM);
+ bcr |= FMC2_BCR_EXTMOD;
+ btr |= FIELD_PREP(FMC2_BXTR_ACCMOD, FMC2_BXTR_EXTMOD_A);
+ bwtr |= FIELD_PREP(FMC2_BXTR_ACCMOD, FMC2_BXTR_EXTMOD_A);
+ break;
+ case FMC2_ASYNC_MODE_2_NOR:
+ /*
+ * MUXEN = 0, MTYP = 2, FACCEN = 1, BURSTEN = 0, WAITEN = 0,
+ * WREN = 1, EXTMOD = 0, CBURSTRW = 0, ACCMOD = 0
+ */
+ bcr |= FIELD_PREP(FMC2_BCR_MTYP, FMC2_BCR_MTYP_NOR);
+ bcr |= FMC2_BCR_FACCEN;
+ break;
+ case FMC2_ASYNC_MODE_B_NOR:
+ /*
+ * MUXEN = 0, MTYP = 2, FACCEN = 1, BURSTEN = 0, WAITEN = 0,
+ * WREN = 1, EXTMOD = 1, CBURSTRW = 0, ACCMOD = 1
+ */
+ bcr |= FIELD_PREP(FMC2_BCR_MTYP, FMC2_BCR_MTYP_NOR);
+ bcr |= FMC2_BCR_FACCEN | FMC2_BCR_EXTMOD;
+ btr |= FIELD_PREP(FMC2_BXTR_ACCMOD, FMC2_BXTR_EXTMOD_B);
+ bwtr |= FIELD_PREP(FMC2_BXTR_ACCMOD, FMC2_BXTR_EXTMOD_B);
+ break;
+ case FMC2_ASYNC_MODE_C_NOR:
+ /*
+ * MUXEN = 0, MTYP = 2, FACCEN = 1, BURSTEN = 0, WAITEN = 0,
+ * WREN = 1, EXTMOD = 1, CBURSTRW = 0, ACCMOD = 2
+ */
+ bcr |= FIELD_PREP(FMC2_BCR_MTYP, FMC2_BCR_MTYP_NOR);
+ bcr |= FMC2_BCR_FACCEN | FMC2_BCR_EXTMOD;
+ btr |= FIELD_PREP(FMC2_BXTR_ACCMOD, FMC2_BXTR_EXTMOD_C);
+ bwtr |= FIELD_PREP(FMC2_BXTR_ACCMOD, FMC2_BXTR_EXTMOD_C);
+ break;
+ case FMC2_ASYNC_MODE_D_NOR:
+ /*
+ * MUXEN = 0, MTYP = 2, FACCEN = 1, BURSTEN = 0, WAITEN = 0,
+ * WREN = 1, EXTMOD = 1, CBURSTRW = 0, ACCMOD = 3
+ */
+ bcr |= FIELD_PREP(FMC2_BCR_MTYP, FMC2_BCR_MTYP_NOR);
+ bcr |= FMC2_BCR_FACCEN | FMC2_BCR_EXTMOD;
+ btr |= FIELD_PREP(FMC2_BXTR_ACCMOD, FMC2_BXTR_EXTMOD_D);
+ bwtr |= FIELD_PREP(FMC2_BXTR_ACCMOD, FMC2_BXTR_EXTMOD_D);
+ break;
+ case FMC2_SYNC_READ_SYNC_WRITE_PSRAM:
+ /*
+ * MUXEN = 0, MTYP = 1, FACCEN = 0, BURSTEN = 1, WAITEN = 0,
+ * WREN = 1, EXTMOD = 0, CBURSTRW = 1, ACCMOD = 0
+ */
+ bcr |= FIELD_PREP(FMC2_BCR_MTYP, FMC2_BCR_MTYP_PSRAM);
+ bcr |= FMC2_BCR_BURSTEN | FMC2_BCR_CBURSTRW;
+ break;
+ case FMC2_SYNC_READ_ASYNC_WRITE_PSRAM:
+ /*
+ * MUXEN = 0, MTYP = 1, FACCEN = 0, BURSTEN = 1, WAITEN = 0,
+ * WREN = 1, EXTMOD = 0, CBURSTRW = 0, ACCMOD = 0
+ */
+ bcr |= FIELD_PREP(FMC2_BCR_MTYP, FMC2_BCR_MTYP_PSRAM);
+ bcr |= FMC2_BCR_BURSTEN;
+ break;
+ case FMC2_SYNC_READ_SYNC_WRITE_NOR:
+ /*
+ * MUXEN = 0, MTYP = 2, FACCEN = 1, BURSTEN = 1, WAITEN = 0,
+ * WREN = 1, EXTMOD = 0, CBURSTRW = 1, ACCMOD = 0
+ */
+ bcr |= FIELD_PREP(FMC2_BCR_MTYP, FMC2_BCR_MTYP_NOR);
+ bcr |= FMC2_BCR_FACCEN | FMC2_BCR_BURSTEN | FMC2_BCR_CBURSTRW;
+ break;
+ case FMC2_SYNC_READ_ASYNC_WRITE_NOR:
+ /*
+ * MUXEN = 0, MTYP = 2, FACCEN = 1, BURSTEN = 1, WAITEN = 0,
+ * WREN = 1, EXTMOD = 0, CBURSTRW = 0, ACCMOD = 0
+ */
+ bcr |= FIELD_PREP(FMC2_BCR_MTYP, FMC2_BCR_MTYP_NOR);
+ bcr |= FMC2_BCR_FACCEN | FMC2_BCR_BURSTEN;
+ break;
+ default:
+ /* Type of transaction not supported */
+ return -EINVAL;
+ }
+
+ if (bcr & FMC2_BCR_EXTMOD)
+ regmap_update_bits(fmc2->regmap, FMC2_BWTR(cs),
+ bwtr_mask, bwtr);
+ regmap_update_bits(fmc2->regmap, FMC2_BTR(cs), btr_mask, btr);
+ regmap_update_bits(fmc2->regmap, FMC2_BCR(cs), bcr_mask, bcr);
+
+ return 0;
+}
+
+static int stm32_fmc2_ebi_set_buswidth(struct stm32_fmc2 *fmc2,
+ const struct stm32_fmc2_prop *prop,
+ int cs, u32 setup)
+{
+ u32 val;
+
+ switch (setup) {
+ case FMC2_BUSWIDTH_8:
+ val = FIELD_PREP(FMC2_BCR_MWID, FMC2_BCR_MWID_8);
+ break;
+ case FMC2_BUSWIDTH_16:
+ val = FIELD_PREP(FMC2_BCR_MWID, FMC2_BCR_MWID_16);
+ break;
+ default:
+ /* Buswidth not supported */
+ return -EINVAL;
+ }
+
+ regmap_update_bits(fmc2->regmap, FMC2_BCR(cs), FMC2_BCR_MWID, val);
+
+ return 0;
+}
+
+static int stm32_fmc2_ebi_set_cpsize(struct stm32_fmc2 *fmc2,
+ const struct stm32_fmc2_prop *prop,
+ int cs, u32 setup)
+{
+ u32 val;
+
+ switch (setup) {
+ case FMC2_CPSIZE_0:
+ val = FIELD_PREP(FMC2_BCR_CPSIZE, FMC2_BCR_CPSIZE_0);
+ break;
+ case FMC2_CPSIZE_128:
+ val = FIELD_PREP(FMC2_BCR_CPSIZE, FMC2_BCR_CPSIZE_128);
+ break;
+ case FMC2_CPSIZE_256:
+ val = FIELD_PREP(FMC2_BCR_CPSIZE, FMC2_BCR_CPSIZE_256);
+ break;
+ case FMC2_CPSIZE_512:
+ val = FIELD_PREP(FMC2_BCR_CPSIZE, FMC2_BCR_CPSIZE_512);
+ break;
+ case FMC2_CPSIZE_1024:
+ val = FIELD_PREP(FMC2_BCR_CPSIZE, FMC2_BCR_CPSIZE_1024);
+ break;
+ default:
+ /* Cpsize not supported */
+ return -EINVAL;
+ }
+
+ regmap_update_bits(fmc2->regmap, FMC2_BCR(cs), FMC2_BCR_CPSIZE, val);
+
+ return 0;
+}
+
+static int stm32_fmc2_ebi_set_bl_setup(struct stm32_fmc2 *fmc2,
+ const struct stm32_fmc2_prop *prop,
+ int cs, u32 setup)
+{
+ u32 val;
+
+ val = min_t(u32, setup, FMC2_BCR_NBLSET_MAX);
+ val = FIELD_PREP(FMC2_BCR_NBLSET, val);
+ regmap_update_bits(fmc2->regmap, FMC2_BCR(cs), FMC2_BCR_NBLSET, val);
+
+ return 0;
+}
+
+static int stm32_fmc2_ebi_set_address_setup(struct stm32_fmc2 *fmc2,
+ const struct stm32_fmc2_prop *prop,
+ int cs, u32 setup)
+{
+ u32 bcr, bxtr, reg;
+ u32 val = FIELD_PREP(FMC2_BXTR_ACCMOD, FMC2_BXTR_EXTMOD_D);
+ int ret;
+
+ ret = stm32_fmc2_ebi_get_reg(prop->reg_type, cs, ®);
+ if (ret)
+ return ret;
+
+ regmap_read(fmc2->regmap, FMC2_BCR(cs), &bcr);
+ if (prop->reg_type == FMC2_REG_BWTR)
+ regmap_read(fmc2->regmap, FMC2_BWTR(cs), &bxtr);
+ else
+ regmap_read(fmc2->regmap, FMC2_BTR(cs), &bxtr);
+
+ if ((bxtr & FMC2_BXTR_ACCMOD) == val || bcr & FMC2_BCR_MUXEN)
+ val = clamp_val(setup, 1, FMC2_BXTR_ADDSET_MAX);
+ else
+ val = min_t(u32, setup, FMC2_BXTR_ADDSET_MAX);
+ val = FIELD_PREP(FMC2_BXTR_ADDSET, val);
+ regmap_update_bits(fmc2->regmap, reg, FMC2_BXTR_ADDSET, val);
+
+ return 0;
+}
+
+static int stm32_fmc2_ebi_set_address_hold(struct stm32_fmc2 *fmc2,
+ const struct stm32_fmc2_prop *prop,
+ int cs, u32 setup)
+{
+ u32 val, reg;
+ int ret;
+
+ ret = stm32_fmc2_ebi_get_reg(prop->reg_type, cs, ®);
+ if (ret)
+ return ret;
+
+ val = clamp_val(setup, 1, FMC2_BXTR_ADDHLD_MAX);
+ val = FIELD_PREP(FMC2_BXTR_ADDHLD, val);
+ regmap_update_bits(fmc2->regmap, reg, FMC2_BXTR_ADDHLD, val);
+
+ return 0;
+}
+
+static int stm32_fmc2_ebi_set_data_setup(struct stm32_fmc2 *fmc2,
+ const struct stm32_fmc2_prop *prop,
+ int cs, u32 setup)
+{
+ u32 val, reg;
+ int ret;
+
+ ret = stm32_fmc2_ebi_get_reg(prop->reg_type, cs, ®);
+ if (ret)
+ return ret;
+
+ val = clamp_val(setup, 1, FMC2_BXTR_DATAST_MAX);
+ val = FIELD_PREP(FMC2_BXTR_DATAST, val);
+ regmap_update_bits(fmc2->regmap, reg, FMC2_BXTR_DATAST, val);
+
+ return 0;
+}
+
+static int stm32_fmc2_ebi_set_bus_turnaround(struct stm32_fmc2 *fmc2,
+ const struct stm32_fmc2_prop *prop,
+ int cs, u32 setup)
+{
+ u32 val, reg;
+ int ret;
+
+ ret = stm32_fmc2_ebi_get_reg(prop->reg_type, cs, ®);
+ if (ret)
+ return ret;
+
+ val = setup ? min_t(u32, setup - 1, FMC2_BXTR_BUSTURN_MAX) : 0;
+ val = FIELD_PREP(FMC2_BXTR_BUSTURN, val);
+ regmap_update_bits(fmc2->regmap, reg, FMC2_BXTR_BUSTURN, val);
+
+ return 0;
+}
+
+static int stm32_fmc2_ebi_set_data_hold(struct stm32_fmc2 *fmc2,
+ const struct stm32_fmc2_prop *prop,
+ int cs, u32 setup)
+{
+ u32 val, reg;
+ int ret;
+
+ ret = stm32_fmc2_ebi_get_reg(prop->reg_type, cs, ®);
+ if (ret)
+ return ret;
+
+ if (prop->reg_type == FMC2_REG_BWTR)
+ val = setup ? min_t(u32, setup - 1, FMC2_BXTR_DATAHLD_MAX) : 0;
+ else
+ val = min_t(u32, setup, FMC2_BXTR_DATAHLD_MAX);
+ val = FIELD_PREP(FMC2_BXTR_DATAHLD, val);
+ regmap_update_bits(fmc2->regmap, reg, FMC2_BXTR_DATAHLD, val);
+
+ return 0;
+}
+
+static int stm32_fmc2_ebi_set_clk_period(struct stm32_fmc2 *fmc2,
+ const struct stm32_fmc2_prop *prop,
+ int cs, u32 setup)
+{
+ u32 val;
+
+ val = setup ? clamp_val(setup - 1, 1, FMC2_BTR_CLKDIV_MAX) : 1;
+ val = FIELD_PREP(FMC2_BTR_CLKDIV, val);
+ regmap_update_bits(fmc2->regmap, FMC2_BTR(cs), FMC2_BTR_CLKDIV, val);
+
+ return 0;
+}
+
+static int stm32_fmc2_ebi_set_data_latency(struct stm32_fmc2 *fmc2,
+ const struct stm32_fmc2_prop *prop,
+ int cs, u32 setup)
+{
+ u32 val;
+
+ val = min_t(u32, setup, FMC2_BTR_DATLAT_MAX);
+ val = FIELD_PREP(FMC2_BTR_DATLAT, val);
+ regmap_update_bits(fmc2->regmap, FMC2_BTR(cs), FMC2_BTR_DATLAT, val);
+
+ return 0;
+}
+
+static int stm32_fmc2_ebi_set_max_low_pulse(struct stm32_fmc2 *fmc2,
+ const struct stm32_fmc2_prop *prop,
+ int cs, u32 setup)
+{
+ u32 old_val, new_val, pcscntr;
+
+ if (setup < 1)
+ return 0;
+
+ regmap_read(fmc2->regmap, FMC2_PCSCNTR, &pcscntr);
+
+ /* Enable counter for the bank */
+ regmap_update_bits(fmc2->regmap, FMC2_PCSCNTR,
+ FMC2_PCSCNTR_CNTBEN(cs),
+ FMC2_PCSCNTR_CNTBEN(cs));
+
+ new_val = min_t(u32, setup - 1, FMC2_PCSCNTR_CSCOUNT_MAX);
+ old_val = FIELD_GET(FMC2_PCSCNTR_CSCOUNT, pcscntr);
+ if (old_val && new_val > old_val)
+ /* Keep current counter value */
+ return 0;
+
+ new_val = FIELD_PREP(FMC2_PCSCNTR_CSCOUNT, new_val);
+ regmap_update_bits(fmc2->regmap, FMC2_PCSCNTR,
+ FMC2_PCSCNTR_CSCOUNT, new_val);
+
+ return 0;
+}
+
+static const struct stm32_fmc2_prop stm32_fmc2_child_props[] = {
+ /* st,fmc2_ebi_cs_trans_type must be the first property */
+ {
+ .name = "st,fmc2_ebi_cs_transaction_type",
+ .mprop = true,
+ .set = stm32_fmc2_ebi_set_trans_type,
+ },
+ {
+ .name = "st,fmc2_ebi_cs_cclk_enable",
+ .bprop = true,
+ .reg_type = FMC2_REG_BCR,
+ .reg_mask = FMC2_BCR1_CCLKEN,
+ .check = stm32_fmc2_ebi_check_cclk,
+ .set = stm32_fmc2_ebi_set_bit_field,
+ },
+ {
+ .name = "st,fmc2_ebi_cs_mux_enable",
+ .bprop = true,
+ .reg_type = FMC2_REG_BCR,
+ .reg_mask = FMC2_BCR_MUXEN,
+ .check = stm32_fmc2_ebi_check_mux,
+ .set = stm32_fmc2_ebi_set_bit_field,
+ },
+ {
+ .name = "st,fmc2_ebi_cs_buswidth",
+ .reset_val = FMC2_BUSWIDTH_16,
+ .set = stm32_fmc2_ebi_set_buswidth,
+ },
+ {
+ .name = "st,fmc2_ebi_cs_waitpol_high",
+ .bprop = true,
+ .reg_type = FMC2_REG_BCR,
+ .reg_mask = FMC2_BCR_WAITPOL,
+ .set = stm32_fmc2_ebi_set_bit_field,
+ },
+ {
+ .name = "st,fmc2_ebi_cs_waitcfg_enable",
+ .bprop = true,
+ .reg_type = FMC2_REG_BCR,
+ .reg_mask = FMC2_BCR_WAITCFG,
+ .check = stm32_fmc2_ebi_check_waitcfg,
+ .set = stm32_fmc2_ebi_set_bit_field,
+ },
+ {
+ .name = "st,fmc2_ebi_cs_wait_enable",
+ .bprop = true,
+ .reg_type = FMC2_REG_BCR,
+ .reg_mask = FMC2_BCR_WAITEN,
+ .check = stm32_fmc2_ebi_check_sync_trans,
+ .set = stm32_fmc2_ebi_set_bit_field,
+ },
+ {
+ .name = "st,fmc2_ebi_cs_asyncwait_enable",
+ .bprop = true,
+ .reg_type = FMC2_REG_BCR,
+ .reg_mask = FMC2_BCR_ASYNCWAIT,
+ .check = stm32_fmc2_ebi_check_async_trans,
+ .set = stm32_fmc2_ebi_set_bit_field,
+ },
+ {
+ .name = "st,fmc2_ebi_cs_cpsize",
+ .check = stm32_fmc2_ebi_check_cpsize,
+ .set = stm32_fmc2_ebi_set_cpsize,
+ },
+ {
+ .name = "st,fmc2_ebi_cs_byte_lane_setup",
+ .calculate = stm32_fmc2_ebi_timing_ns_to_clock_cycles,
+ .set = stm32_fmc2_ebi_set_bl_setup,
+ },
+ {
+ .name = "st,fmc2_ebi_cs_address_setup",
+ .reg_type = FMC2_REG_BTR,
+ .reset_val = FMC2_BXTR_ADDSET_MAX,
+ .check = stm32_fmc2_ebi_check_async_trans,
+ .calculate = stm32_fmc2_ebi_timing_ns_to_clock_cycles,
+ .set = stm32_fmc2_ebi_set_address_setup,
+ },
+ {
+ .name = "st,fmc2_ebi_cs_address_hold",
+ .reg_type = FMC2_REG_BTR,
+ .reset_val = FMC2_BXTR_ADDHLD_MAX,
+ .check = stm32_fmc2_ebi_check_address_hold,
+ .calculate = stm32_fmc2_ebi_timing_ns_to_clock_cycles,
+ .set = stm32_fmc2_ebi_set_address_hold,
+ },
+ {
+ .name = "st,fmc2_ebi_cs_data_setup",
+ .reg_type = FMC2_REG_BTR,
+ .reset_val = FMC2_BXTR_DATAST_MAX,
+ .check = stm32_fmc2_ebi_check_async_trans,
+ .calculate = stm32_fmc2_ebi_timing_ns_to_clock_cycles,
+ .set = stm32_fmc2_ebi_set_data_setup,
+ },
+ {
+ .name = "st,fmc2_ebi_cs_bus_turnaround",
+ .reg_type = FMC2_REG_BTR,
+ .reset_val = FMC2_BXTR_BUSTURN_MAX + 1,
+ .calculate = stm32_fmc2_ebi_timing_ns_to_clock_cycles,
+ .set = stm32_fmc2_ebi_set_bus_turnaround,
+ },
+ {
+ .name = "st,fmc2_ebi_cs_data_hold",
+ .reg_type = FMC2_REG_BTR,
+ .check = stm32_fmc2_ebi_check_async_trans,
+ .calculate = stm32_fmc2_ebi_timing_ns_to_clock_cycles,
+ .set = stm32_fmc2_ebi_set_data_hold,
+ },
+ {
+ .name = "st,fmc2_ebi_cs_clk_period",
+ .reset_val = FMC2_BTR_CLKDIV_MAX + 1,
+ .check = stm32_fmc2_ebi_check_clk_period,
+ .calculate = stm32_fmc2_ebi_timing_ns_to_clock_cycles,
+ .set = stm32_fmc2_ebi_set_clk_period,
+ },
+ {
+ .name = "st,fmc2_ebi_cs_data_latency",
+ .check = stm32_fmc2_ebi_check_sync_trans,
+ .set = stm32_fmc2_ebi_set_data_latency,
+ },
+ {
+ .name = "st,fmc2_ebi_cs_write_address_setup",
+ .reg_type = FMC2_REG_BWTR,
+ .reset_val = FMC2_BXTR_ADDSET_MAX,
+ .check = stm32_fmc2_ebi_check_async_trans,
+ .calculate = stm32_fmc2_ebi_timing_ns_to_clock_cycles,
+ .set = stm32_fmc2_ebi_set_address_setup,
+ },
+ {
+ .name = "st,fmc2_ebi_cs_write_address_hold",
+ .reg_type = FMC2_REG_BWTR,
+ .reset_val = FMC2_BXTR_ADDHLD_MAX,
+ .check = stm32_fmc2_ebi_check_address_hold,
+ .calculate = stm32_fmc2_ebi_timing_ns_to_clock_cycles,
+ .set = stm32_fmc2_ebi_set_address_hold,
+ },
+ {
+ .name = "st,fmc2_ebi_cs_write_data_setup",
+ .reg_type = FMC2_REG_BWTR,
+ .reset_val = FMC2_BXTR_DATAST_MAX,
+ .check = stm32_fmc2_ebi_check_async_trans,
+ .calculate = stm32_fmc2_ebi_timing_ns_to_clock_cycles,
+ .set = stm32_fmc2_ebi_set_data_setup,
+ },
+ {
+ .name = "st,fmc2_ebi_cs_write_bus_turnaround",
+ .reg_type = FMC2_REG_BWTR,
+ .reset_val = FMC2_BXTR_BUSTURN_MAX + 1,
+ .calculate = stm32_fmc2_ebi_timing_ns_to_clock_cycles,
+ .set = stm32_fmc2_ebi_set_bus_turnaround,
+ },
+ {
+ .name = "st,fmc2_ebi_cs_write_data_hold",
+ .reg_type = FMC2_REG_BWTR,
+ .check = stm32_fmc2_ebi_check_async_trans,
+ .calculate = stm32_fmc2_ebi_timing_ns_to_clock_cycles,
+ .set = stm32_fmc2_ebi_set_data_hold,
+ },
+ {
+ .name = "st,fmc2_ebi_cs_max_low_pulse",
+ .calculate = stm32_fmc2_ebi_timing_ns_to_clock_cycles,
+ .set = stm32_fmc2_ebi_set_max_low_pulse,
+ },
+};
+
+static void stm32_fmc2_ebi_set_bank(struct stm32_fmc2 *fmc2,
+ int cs, bool enable)
+{
+ regmap_update_bits(fmc2->regmap, FMC2_BCR(cs), FMC2_BCR_MBKEN,
+ enable ? FMC2_BCR_MBKEN : 0);
+}
+
+static int stm32_fmc2_ebi_parse_prop(struct device *dev,
+ struct device_node *dev_node,
+ const struct stm32_fmc2_prop *prop,
+ int cs)
+{
+ struct stm32_fmc2 *fmc2 = dev_get_drvdata(dev->parent);
+ u32 setup = 0;
+
+ if (!prop->set) {
+ dev_err(dev, "property %s is not well defined\n", prop->name);
+ return -EINVAL;
+ }
+
+ if (prop->check && prop->check(fmc2, prop, cs))
+ /* Skeep this property */
+ return 0;
+
+ if (prop->bprop) {
+ const __be32 *bprop = of_get_property(dev_node,
+ prop->name, NULL);
+
+ if (prop->mprop && !bprop) {
+ dev_err(dev, "mandatory property %s not defined in the device tree\n",
+ prop->name);
+ return -EINVAL;
+ }
+
+ if (bprop)
+ setup = 1;
+ } else {
+ u32 val;
+ int ret;
+
+ ret = of_property_read_u32(dev_node, prop->name, &val);
+ if (prop->mprop && ret) {
+ dev_err(dev, "mandatory property %s not defined in the device tree\n",
+ prop->name);
+ return ret;
+ }
+
+ if (ret)
+ setup = prop->reset_val;
+ else if (prop->calculate)
+ setup = prop->calculate(fmc2, val);
+ else
+ setup = val;
+ }
+
+ return prop->set(fmc2, prop, cs, setup);
+}
+
+static int stm32_fmc2_ebi_setup_cs(struct device *dev,
+ struct device_node *dev_node,
+ u32 cs)
+{
+ struct stm32_fmc2 *fmc2 = dev_get_drvdata(dev->parent);
+ int i, ret;
+
+ /* Disable the bank */
+ stm32_fmc2_ebi_set_bank(fmc2, cs, false);
+
+ for (i = 0; i < ARRAY_SIZE(stm32_fmc2_child_props); i++) {
+ const struct stm32_fmc2_prop *p = &stm32_fmc2_child_props[i];
+
+ ret = stm32_fmc2_ebi_parse_prop(dev, dev_node, p, cs);
+ if (ret) {
+ dev_err(dev, "property %s could not be set: %d\n",
+ p->name, ret);
+ return ret;
+ }
+ }
+
+ /* Enable the bank */
+ stm32_fmc2_ebi_set_bank(fmc2, cs, true);
+
+ return 0;
+}
+
+static int stm32_fmc2_ebi_parse_dt(struct device *dev,
+ struct stm32_fmc2_ebi *ebi)
+{
+ struct device_node *child;
+ bool child_found = false;
+ u32 cs;
+ int ret;
+
+ for_each_available_child_of_node(dev->of_node, child) {
+ ret = of_property_read_u32(child, "reg", &cs);
+ if (ret) {
+ dev_err(dev, "could not retrieve reg property: %d\n",
+ ret);
+ return ret;
+ }
+
+ if (cs > FMC2_MAX_EBI_CE) {
+ dev_err(dev, "invalid reg value: %d\n", cs);
+ return -EINVAL;
+ }
+
+ if (ebi->cs_assigned & BIT(cs)) {
+ dev_err(dev, "cs already assigned: %d\n", cs);
+ return -EINVAL;
+ }
+
+ ret = stm32_fmc2_ebi_setup_cs(dev, child, cs);
+ if (ret) {
+ dev_err(dev, "setup chip select %d failed: %d\n",
+ cs, ret);
+ return ret;
+ }
+
+ ebi->cs_assigned |= BIT(cs);
+ child_found = true;
+ }
+
+ if (!child_found) {
+ dev_warn(dev, "no subnodes found, disable the driver.\n");
+ return -ENODEV;
+ }
+
+ return of_platform_default_populate(dev->of_node, NULL, dev);
+}
+
+static void stm32_fmc2_ebi_save_setup(struct stm32_fmc2 *fmc2,
+ struct stm32_fmc2_ebi *ebi)
+{
+ unsigned int cs;
+
+ for (cs = 0; cs < FMC2_MAX_EBI_CE; cs++) {
+ regmap_read(fmc2->regmap, FMC2_BCR(cs), &ebi->bcr[cs]);
+ regmap_read(fmc2->regmap, FMC2_BTR(cs), &ebi->btr[cs]);
+ regmap_read(fmc2->regmap, FMC2_BWTR(cs), &ebi->bwtr[cs]);
+ }
+
+ regmap_read(fmc2->regmap, FMC2_PCSCNTR, &ebi->pcscntr);
+}
+
+static void stm32_fmc2_ebi_set_setup(struct stm32_fmc2 *fmc2,
+ struct stm32_fmc2_ebi *ebi)
+{
+ unsigned int cs;
+
+ for (cs = 0; cs < FMC2_MAX_EBI_CE; cs++) {
+ regmap_write(fmc2->regmap, FMC2_BCR(cs), ebi->bcr[cs]);
+ regmap_write(fmc2->regmap, FMC2_BTR(cs), ebi->btr[cs]);
+ regmap_write(fmc2->regmap, FMC2_BWTR(cs), ebi->bwtr[cs]);
+ }
+
+ regmap_write(fmc2->regmap, FMC2_PCSCNTR, ebi->pcscntr);
+}
+
+static bool stm32_fmc2_ebi_check_nwait_is_used(struct stm32_fmc2 *fmc2,
+ struct stm32_fmc2_ebi *ebi)
+{
+ unsigned int cs;
+ u32 bcr;
+
+ for (cs = 0; cs < FMC2_MAX_EBI_CE; cs++) {
+ if (!(ebi->cs_assigned & BIT(cs)))
+ continue;
+
+ regmap_read(fmc2->regmap, FMC2_BCR(cs), &bcr);
+ if (bcr & FMC2_BCR_WAITEN || bcr & FMC2_BCR_ASYNCWAIT)
+ return true;
+ }
+
+ return false;
+}
+
+static void stm32_fmc2_ebi_disable_banks(struct stm32_fmc2 *fmc2,
+ struct stm32_fmc2_ebi *ebi)
+{
+ unsigned int cs;
+
+ for (cs = 0; cs < FMC2_MAX_EBI_CE; cs++) {
+ if (!(ebi->cs_assigned & BIT(cs)))
+ continue;
+
+ stm32_fmc2_ebi_set_bank(fmc2, cs, false);
+ }
+}
+
+static int stm32_fmc2_ebi_probe(struct platform_device *pdev)
+{
+ struct stm32_fmc2 *fmc2 = dev_get_drvdata(pdev->dev.parent);
+ struct stm32_fmc2_ebi *ebi;
+ int ret;
+
+ ebi = devm_kzalloc(&pdev->dev, sizeof(*ebi), GFP_KERNEL);
+ if (!ebi)
+ return -ENOMEM;
+
+ ret = clk_prepare_enable(fmc2->clk);
+ if (ret)
+ return ret;
+
+ ret = stm32_fmc2_ebi_parse_dt(&pdev->dev, ebi);
+ if (ret)
+ goto out;
+
+ if (stm32_fmc2_ebi_check_nwait_is_used(fmc2, ebi) &&
+ atomic_inc_return(&fmc2->nwait_is_used) > 1) {
+ dev_err(&pdev->dev,
+ "NWAIT signal in used by a FMC controller\n");
+ atomic_dec(&fmc2->nwait_is_used);
+ ret = -EINVAL;
+ goto out;
+ }
+
+ stm32_fmc2_ebi_save_setup(fmc2, ebi);
+ fmc2->enable(fmc2);
+ platform_set_drvdata(pdev, ebi);
+
+ return 0;
+
+out:
+ stm32_fmc2_ebi_disable_banks(fmc2, ebi);
+ clk_disable_unprepare(fmc2->clk);
+
+ return ret;
+}
+
+static int stm32_fmc2_ebi_remove(struct platform_device *pdev)
+{
+ struct stm32_fmc2 *fmc2 = dev_get_drvdata(pdev->dev.parent);
+ struct stm32_fmc2_ebi *ebi = platform_get_drvdata(pdev);
+
+ if (stm32_fmc2_ebi_check_nwait_is_used(fmc2, ebi))
+ atomic_dec(&fmc2->nwait_is_used);
+ stm32_fmc2_ebi_disable_banks(fmc2, ebi);
+ fmc2->disable(fmc2);
+ clk_disable_unprepare(fmc2->clk);
+
+ return 0;
+}
+
+static int __maybe_unused stm32_fmc2_ebi_suspend(struct device *dev)
+{
+ struct stm32_fmc2 *fmc2 = dev_get_drvdata(dev->parent);
+
+ fmc2->disable(fmc2);
+ clk_disable_unprepare(fmc2->clk);
+
+ return 0;
+}
+
+static int __maybe_unused stm32_fmc2_ebi_resume(struct device *dev)
+{
+ struct stm32_fmc2 *fmc2 = dev_get_drvdata(dev->parent);
+ struct stm32_fmc2_ebi *ebi = dev_get_drvdata(dev);
+ int ret;
+
+ ret = clk_prepare_enable(fmc2->clk);
+ if (ret)
+ return ret;
+
+ stm32_fmc2_ebi_set_setup(fmc2, ebi);
+ fmc2->enable(fmc2);
+
+ return 0;
+}
+
+static SIMPLE_DEV_PM_OPS(stm32_fmc2_ebi_pm_ops, stm32_fmc2_ebi_suspend,
+ stm32_fmc2_ebi_resume);
+
+static const struct of_device_id stm32_fmc2_ebi_match[] = {
+ {.compatible = "st,stm32mp1-fmc2-ebi"},
+ {}
+};
+MODULE_DEVICE_TABLE(of, stm32_fmc2_ebi_match);
+
+static struct platform_driver stm32_fmc2_ebi_driver = {
+ .probe = stm32_fmc2_ebi_probe,
+ .remove = stm32_fmc2_ebi_remove,
+ .driver = {
+ .name = "stm32_fmc2_ebi",
+ .of_match_table = stm32_fmc2_ebi_match,
+ .pm = &stm32_fmc2_ebi_pm_ops,
+ },
+};
+module_platform_driver(stm32_fmc2_ebi_driver);
+
+MODULE_ALIAS("platform:stm32_fmc2_ebi");
+MODULE_AUTHOR("Christophe Kerello <christophe.kerello@st.com>");
+MODULE_DESCRIPTION("STMicroelectronics STM32 FMC2 ebi driver");
+MODULE_LICENSE("GPL v2");
The driver adds the support for the STMicroelectronics FMC2 EBI controller found on STM32MP SOCs. Signed-off-by: Christophe Kerello <christophe.kerello@st.com> --- drivers/bus/Kconfig | 11 + drivers/bus/Makefile | 1 + drivers/bus/stm32-fmc2-ebi.c | 1093 ++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 1105 insertions(+) create mode 100644 drivers/bus/stm32-fmc2-ebi.c