[PATCH 1/2] memory: Add driver for FMC2 External Bus Interface on STM32MP SoCs
Alexander Shiyan
eagle.alexander923 at gmail.com
Thu Aug 3 03:32:37 PDT 2023
This adds support for FMC2 External Bus Interface on STM32MP SoCs.
The original source is taken from the STMicroelectronics/u-boot repository [1].
[1] https://github.com/STMicroelectronics/u-boot/blob/v2022.10-stm32mp/drivers/memory/stm32-fmc2-ebi.c
Signed-off-by: Alexander Shiyan <eagle.alexander923 at gmail.com>
---
drivers/memory/Kconfig | 9 +
drivers/memory/Makefile | 1 +
drivers/memory/stm32-fmc2-ebi.c | 1063 +++++++++++++++++++++++++++++++
3 files changed, 1073 insertions(+)
create mode 100644 drivers/memory/stm32-fmc2-ebi.c
diff --git a/drivers/memory/Kconfig b/drivers/memory/Kconfig
index e18b452009..b0d99c3a54 100644
--- a/drivers/memory/Kconfig
+++ b/drivers/memory/Kconfig
@@ -23,4 +23,13 @@ config MC_TEGRA124
the Tegra124 SoC. This driver performs the necessary initialization
to provide a function GPU when the OS is running.
+config STM32_FMC2_EBI
+ bool "Support for FMC2 External Bus Interface on STM32MP SoCs"
+ depends on ARCH_STM32MP || COMPILE_TEST
+ 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.
+
endmenu
diff --git a/drivers/memory/Makefile b/drivers/memory/Makefile
index bdf8db66e8..67d3c47621 100644
--- a/drivers/memory/Makefile
+++ b/drivers/memory/Makefile
@@ -1,3 +1,4 @@
# SPDX-License-Identifier: GPL-2.0-only
obj-$(CONFIG_ATMEL_EBI) += atmel-ebi.o
obj-$(CONFIG_MC_TEGRA124) += mc-tegra124.o
+obj-$(CONFIG_STM32_FMC2_EBI) += stm32-fmc2-ebi.o
diff --git a/drivers/memory/stm32-fmc2-ebi.c b/drivers/memory/stm32-fmc2-ebi.c
new file mode 100644
index 0000000000..ac2ea1b0e0
--- /dev/null
+++ b/drivers/memory/stm32-fmc2-ebi.c
@@ -0,0 +1,1063 @@
+// SPDX-License-Identifier: GPL-2.0+ OR BSD-3-Clause
+/*
+ * Copyright (C) STMicroelectronics 2020
+ */
+
+#define pr_fmt(fmt) "stm32-fmc2-ebi: " fmt
+
+#include <common.h>
+#include <init.h>
+#include <of_address.h>
+#include <linux/bitfield.h>
+#include <linux/clk.h>
+#include <linux/reset.h>
+
+/* FMC2 Controller Registers */
+#define FMC2_BCR1 0x0
+#define FMC2_BTR1 0x4
+#define FMC2_BCR(x) ((x) * 0x8 + FMC2_BCR1)
+#define FMC2_BTR(x) ((x) * 0x8 + FMC2_BTR1)
+#define FMC2_PCSCNTR 0x20
+#define FMC2_BWTR1 0x104
+#define FMC2_BWTR(x) ((x) * 0x8 + FMC2_BWTR1)
+
+/* Register: FMC2_BCR1 */
+#define FMC2_BCR1_CCLKEN BIT(20)
+#define FMC2_BCR1_FMC2EN BIT(31)
+
+/* Register: FMC2_BCRx */
+#define FMC2_BCR_MBKEN BIT(0)
+#define FMC2_BCR_MUXEN BIT(1)
+#define FMC2_BCR_MTYP GENMASK(3, 2)
+#define FMC2_BCR_MWID GENMASK(5, 4)
+#define FMC2_BCR_FACCEN BIT(6)
+#define FMC2_BCR_BURSTEN BIT(8)
+#define FMC2_BCR_WAITPOL BIT(9)
+#define FMC2_BCR_WAITCFG BIT(11)
+#define FMC2_BCR_WREN BIT(12)
+#define FMC2_BCR_WAITEN BIT(13)
+#define FMC2_BCR_EXTMOD BIT(14)
+#define FMC2_BCR_ASYNCWAIT BIT(15)
+#define FMC2_BCR_CPSIZE GENMASK(18, 16)
+#define FMC2_BCR_CBURSTRW BIT(19)
+#define FMC2_BCR_NBLSET GENMASK(23, 22)
+
+/* Register: FMC2_BTRx/FMC2_BWTRx */
+#define FMC2_BXTR_ADDSET GENMASK(3, 0)
+#define FMC2_BXTR_ADDHLD GENMASK(7, 4)
+#define FMC2_BXTR_DATAST GENMASK(15, 8)
+#define FMC2_BXTR_BUSTURN GENMASK(19, 16)
+#define FMC2_BTR_CLKDIV GENMASK(23, 20)
+#define FMC2_BTR_DATLAT GENMASK(27, 24)
+#define FMC2_BXTR_ACCMOD GENMASK(29, 28)
+#define FMC2_BXTR_DATAHLD GENMASK(31, 30)
+
+/* Register: FMC2_PCSCNTR */
+#define FMC2_PCSCNTR_CSCOUNT GENMASK(15, 0)
+#define FMC2_PCSCNTR_CNTBEN(x) BIT((x) + 16)
+
+#define FMC2_MAX_EBI_CE 4
+#define FMC2_MAX_BANKS 5
+
+#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_bank {
+ FMC2_EBI1 = 0,
+ FMC2_EBI2,
+ FMC2_EBI3,
+ FMC2_EBI4,
+ FMC2_NAND
+};
+
+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 {
+ struct clk *clk;
+ void __iomem *io_base;
+ u8 bank_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 nanoseconds in the device tree in clock cycles or in
+ * clock period
+ * @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_ebi *ebi,
+ const struct stm32_fmc2_prop *prop, int cs);
+ u32 (*calculate)(struct stm32_fmc2_ebi *ebi, int cs, u32 setup);
+ int (*set)(struct stm32_fmc2_ebi *ebi,
+ const struct stm32_fmc2_prop *prop,
+ int cs, u32 setup);
+};
+
+static int stm32_fmc2_ebi_check_mux(struct stm32_fmc2_ebi *ebi,
+ const struct stm32_fmc2_prop *prop,
+ int cs)
+{
+ u32 bcr = readl(ebi->io_base + FMC2_BCR(cs));
+
+ if (bcr & FMC2_BCR_MTYP)
+ return 0;
+
+ return -EINVAL;
+}
+
+static int stm32_fmc2_ebi_check_waitcfg(struct stm32_fmc2_ebi *ebi,
+ const struct stm32_fmc2_prop *prop,
+ int cs)
+{
+ u32 bcr = readl(ebi->io_base + FMC2_BCR(cs));
+ u32 val = FIELD_PREP(FMC2_BCR_MTYP, FMC2_BCR_MTYP_NOR);
+
+ 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_ebi *ebi,
+ const struct stm32_fmc2_prop *prop,
+ int cs)
+{
+ u32 bcr = readl(ebi->io_base + FMC2_BCR(cs));
+
+ if (bcr & FMC2_BCR_BURSTEN)
+ return 0;
+
+ return -EINVAL;
+}
+
+static int stm32_fmc2_ebi_check_async_trans(struct stm32_fmc2_ebi *ebi,
+ const struct stm32_fmc2_prop *prop,
+ int cs)
+{
+ u32 bcr = readl(ebi->io_base + FMC2_BCR(cs));
+
+ if (!(bcr & FMC2_BCR_BURSTEN) || !(bcr & FMC2_BCR_CBURSTRW))
+ return 0;
+
+ return -EINVAL;
+}
+
+static int stm32_fmc2_ebi_check_cpsize(struct stm32_fmc2_ebi *ebi,
+ const struct stm32_fmc2_prop *prop,
+ int cs)
+{
+ u32 bcr = readl(ebi->io_base + FMC2_BCR(cs));
+ u32 val = FIELD_PREP(FMC2_BCR_MTYP, FMC2_BCR_MTYP_PSRAM);
+
+ 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_ebi *ebi,
+ const struct stm32_fmc2_prop *prop,
+ int cs)
+{
+ u32 bcr = readl(ebi->io_base + FMC2_BCR(cs));
+ u32 bxtr = prop->reg_type == FMC2_REG_BWTR ?
+ readl(ebi->io_base + FMC2_BWTR(cs)) :
+ readl(ebi->io_base + FMC2_BTR(cs));
+ u32 val = FIELD_PREP(FMC2_BXTR_ACCMOD, FMC2_BXTR_EXTMOD_D);
+
+ 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_ebi *ebi,
+ const struct stm32_fmc2_prop *prop,
+ int cs)
+{
+ u32 bcr = readl(ebi->io_base + FMC2_BCR(cs));
+ u32 bcr1 = cs ? readl(ebi->io_base + FMC2_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_ebi *ebi,
+ const struct stm32_fmc2_prop *prop,
+ int cs)
+{
+ if (cs)
+ return -EINVAL;
+
+ return stm32_fmc2_ebi_check_sync_trans(ebi, prop, cs);
+}
+
+static u32 stm32_fmc2_ebi_ns_to_clock_cycles(struct stm32_fmc2_ebi *ebi,
+ int cs, u32 setup)
+{
+ unsigned long hclk = clk_get_rate(ebi->clk);
+ unsigned long hclkp = NSEC_PER_SEC / (hclk / 1000);
+
+ return DIV_ROUND_UP(setup * 1000, hclkp);
+}
+
+static u32 stm32_fmc2_ebi_ns_to_clk_period(struct stm32_fmc2_ebi *ebi,
+ int cs, u32 setup)
+{
+ u32 nb_clk_cycles = stm32_fmc2_ebi_ns_to_clock_cycles(ebi, cs, setup);
+ u32 bcr = readl(ebi->io_base + FMC2_BCR1);
+ u32 btr = bcr & FMC2_BCR1_CCLKEN || !cs ?
+ readl(ebi->io_base + FMC2_BTR1) :
+ readl(ebi->io_base + FMC2_BTR(cs));
+ u32 clk_period = FIELD_GET(FMC2_BTR_CLKDIV, btr) + 1;
+
+ return DIV_ROUND_UP(nb_clk_cycles, clk_period);
+}
+
+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_ebi *ebi,
+ 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;
+
+ clrsetbits_le32(ebi->io_base + reg, prop->reg_mask,
+ setup ? prop->reg_mask : 0);
+
+ return 0;
+}
+
+static int stm32_fmc2_ebi_set_trans_type(struct stm32_fmc2_ebi *ebi,
+ 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)
+ clrsetbits_le32(ebi->io_base + FMC2_BWTR(cs),
+ bwtr_mask, bwtr);
+ clrsetbits_le32(ebi->io_base + FMC2_BTR(cs), btr_mask, btr);
+ clrsetbits_le32(ebi->io_base + FMC2_BCR(cs), bcr_mask, bcr);
+
+ return 0;
+}
+
+static int stm32_fmc2_ebi_set_buswidth(struct stm32_fmc2_ebi *ebi,
+ 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;
+ }
+
+ clrsetbits_le32(ebi->io_base + FMC2_BCR(cs), FMC2_BCR_MWID, val);
+
+ return 0;
+}
+
+static int stm32_fmc2_ebi_set_cpsize(struct stm32_fmc2_ebi *ebi,
+ 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;
+ }
+
+ clrsetbits_le32(ebi->io_base + FMC2_BCR(cs), FMC2_BCR_CPSIZE, val);
+
+ return 0;
+}
+
+static int stm32_fmc2_ebi_set_bl_setup(struct stm32_fmc2_ebi *ebi,
+ 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);
+ clrsetbits_le32(ebi->io_base + FMC2_BCR(cs), FMC2_BCR_NBLSET, val);
+
+ return 0;
+}
+
+static int stm32_fmc2_ebi_set_address_setup(struct stm32_fmc2_ebi *ebi,
+ const struct stm32_fmc2_prop *prop,
+ int cs, u32 setup)
+{
+ u32 bcr = readl(ebi->io_base + FMC2_BCR(cs));
+ u32 bxtr = prop->reg_type == FMC2_REG_BWTR ?
+ readl(ebi->io_base + FMC2_BWTR(cs)) :
+ readl(ebi->io_base + FMC2_BTR(cs));
+ u32 reg, 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;
+
+ 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);
+ clrsetbits_le32(ebi->io_base + reg, FMC2_BXTR_ADDSET, val);
+
+ return 0;
+}
+
+static int stm32_fmc2_ebi_set_address_hold(struct stm32_fmc2_ebi *ebi,
+ 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);
+ clrsetbits_le32(ebi->io_base + reg, FMC2_BXTR_ADDHLD, val);
+
+ return 0;
+}
+
+static int stm32_fmc2_ebi_set_data_setup(struct stm32_fmc2_ebi *ebi,
+ 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);
+ clrsetbits_le32(ebi->io_base + reg, FMC2_BXTR_DATAST, val);
+
+ return 0;
+}
+
+static int stm32_fmc2_ebi_set_bus_turnaround(struct stm32_fmc2_ebi *ebi,
+ 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);
+ clrsetbits_le32(ebi->io_base + reg, FMC2_BXTR_BUSTURN, val);
+
+ return 0;
+}
+
+static int stm32_fmc2_ebi_set_data_hold(struct stm32_fmc2_ebi *ebi,
+ 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);
+ clrsetbits_le32(ebi->io_base + reg, FMC2_BXTR_DATAHLD, val);
+
+ return 0;
+}
+
+static int stm32_fmc2_ebi_set_clk_period(struct stm32_fmc2_ebi *ebi,
+ 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);
+ clrsetbits_le32(ebi->io_base + FMC2_BTR(cs), FMC2_BTR_CLKDIV, val);
+
+ return 0;
+}
+
+static int stm32_fmc2_ebi_set_data_latency(struct stm32_fmc2_ebi *ebi,
+ const struct stm32_fmc2_prop *prop,
+ int cs, u32 setup)
+{
+ u32 val;
+
+ val = setup > 1 ? min_t(u32, setup - 2, FMC2_BTR_DATLAT_MAX) : 0;
+ val = FIELD_PREP(FMC2_BTR_DATLAT, val);
+ clrsetbits_le32(ebi->io_base + FMC2_BTR(cs), FMC2_BTR_DATLAT, val);
+
+ return 0;
+}
+
+static int stm32_fmc2_ebi_set_max_low_pulse(struct stm32_fmc2_ebi *ebi,
+ const struct stm32_fmc2_prop *prop,
+ int cs, u32 setup)
+{
+ u32 old_val, new_val, pcscntr;
+
+ if (setup < 1)
+ return 0;
+
+ pcscntr = readl(ebi->io_base + FMC2_PCSCNTR);
+
+ /* Enable counter for the bank */
+ setbits_le32(ebi->io_base + FMC2_PCSCNTR, 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);
+ clrsetbits_le32(ebi->io_base + 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-ns",
+ .calculate = stm32_fmc2_ebi_ns_to_clock_cycles,
+ .set = stm32_fmc2_ebi_set_bl_setup,
+ },
+ {
+ .name = "st,fmc2-ebi-cs-address-setup-ns",
+ .reg_type = FMC2_REG_BTR,
+ .reset_val = FMC2_BXTR_ADDSET_MAX,
+ .check = stm32_fmc2_ebi_check_async_trans,
+ .calculate = stm32_fmc2_ebi_ns_to_clock_cycles,
+ .set = stm32_fmc2_ebi_set_address_setup,
+ },
+ {
+ .name = "st,fmc2-ebi-cs-address-hold-ns",
+ .reg_type = FMC2_REG_BTR,
+ .reset_val = FMC2_BXTR_ADDHLD_MAX,
+ .check = stm32_fmc2_ebi_check_address_hold,
+ .calculate = stm32_fmc2_ebi_ns_to_clock_cycles,
+ .set = stm32_fmc2_ebi_set_address_hold,
+ },
+ {
+ .name = "st,fmc2-ebi-cs-data-setup-ns",
+ .reg_type = FMC2_REG_BTR,
+ .reset_val = FMC2_BXTR_DATAST_MAX,
+ .check = stm32_fmc2_ebi_check_async_trans,
+ .calculate = stm32_fmc2_ebi_ns_to_clock_cycles,
+ .set = stm32_fmc2_ebi_set_data_setup,
+ },
+ {
+ .name = "st,fmc2-ebi-cs-bus-turnaround-ns",
+ .reg_type = FMC2_REG_BTR,
+ .reset_val = FMC2_BXTR_BUSTURN_MAX + 1,
+ .calculate = stm32_fmc2_ebi_ns_to_clock_cycles,
+ .set = stm32_fmc2_ebi_set_bus_turnaround,
+ },
+ {
+ .name = "st,fmc2-ebi-cs-data-hold-ns",
+ .reg_type = FMC2_REG_BTR,
+ .check = stm32_fmc2_ebi_check_async_trans,
+ .calculate = stm32_fmc2_ebi_ns_to_clock_cycles,
+ .set = stm32_fmc2_ebi_set_data_hold,
+ },
+ {
+ .name = "st,fmc2-ebi-cs-clk-period-ns",
+ .reset_val = FMC2_BTR_CLKDIV_MAX + 1,
+ .check = stm32_fmc2_ebi_check_clk_period,
+ .calculate = stm32_fmc2_ebi_ns_to_clock_cycles,
+ .set = stm32_fmc2_ebi_set_clk_period,
+ },
+ {
+ .name = "st,fmc2-ebi-cs-data-latency-ns",
+ .check = stm32_fmc2_ebi_check_sync_trans,
+ .calculate = stm32_fmc2_ebi_ns_to_clk_period,
+ .set = stm32_fmc2_ebi_set_data_latency,
+ },
+ {
+ .name = "st,fmc2-ebi-cs-write-address-setup-ns",
+ .reg_type = FMC2_REG_BWTR,
+ .reset_val = FMC2_BXTR_ADDSET_MAX,
+ .check = stm32_fmc2_ebi_check_async_trans,
+ .calculate = stm32_fmc2_ebi_ns_to_clock_cycles,
+ .set = stm32_fmc2_ebi_set_address_setup,
+ },
+ {
+ .name = "st,fmc2-ebi-cs-write-address-hold-ns",
+ .reg_type = FMC2_REG_BWTR,
+ .reset_val = FMC2_BXTR_ADDHLD_MAX,
+ .check = stm32_fmc2_ebi_check_address_hold,
+ .calculate = stm32_fmc2_ebi_ns_to_clock_cycles,
+ .set = stm32_fmc2_ebi_set_address_hold,
+ },
+ {
+ .name = "st,fmc2-ebi-cs-write-data-setup-ns",
+ .reg_type = FMC2_REG_BWTR,
+ .reset_val = FMC2_BXTR_DATAST_MAX,
+ .check = stm32_fmc2_ebi_check_async_trans,
+ .calculate = stm32_fmc2_ebi_ns_to_clock_cycles,
+ .set = stm32_fmc2_ebi_set_data_setup,
+ },
+ {
+ .name = "st,fmc2-ebi-cs-write-bus-turnaround-ns",
+ .reg_type = FMC2_REG_BWTR,
+ .reset_val = FMC2_BXTR_BUSTURN_MAX + 1,
+ .calculate = stm32_fmc2_ebi_ns_to_clock_cycles,
+ .set = stm32_fmc2_ebi_set_bus_turnaround,
+ },
+ {
+ .name = "st,fmc2-ebi-cs-write-data-hold-ns",
+ .reg_type = FMC2_REG_BWTR,
+ .check = stm32_fmc2_ebi_check_async_trans,
+ .calculate = stm32_fmc2_ebi_ns_to_clock_cycles,
+ .set = stm32_fmc2_ebi_set_data_hold,
+ },
+ {
+ .name = "st,fmc2-ebi-cs-max-low-pulse-ns",
+ .calculate = stm32_fmc2_ebi_ns_to_clock_cycles,
+ .set = stm32_fmc2_ebi_set_max_low_pulse,
+ },
+};
+
+static int stm32_fmc2_ebi_parse_prop(struct stm32_fmc2_ebi *ebi,
+ struct device_node *node,
+ const struct stm32_fmc2_prop *prop,
+ int cs)
+{
+ u32 setup = 0;
+
+ if (!prop->set) {
+ pr_err("property %s is not well defined\n", prop->name);
+ return -EINVAL;
+ }
+
+ if (prop->check && prop->check(ebi, prop, cs))
+ /* Skip this property */
+ return 0;
+
+ if (prop->bprop) {
+ bool bprop;
+
+ bprop = of_property_read_bool(node, prop->name);
+ if (prop->mprop && !bprop) {
+ pr_err("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(node, prop->name, &val);
+ if (prop->mprop && ret) {
+ pr_err("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(ebi, cs, val);
+ else
+ setup = val;
+ }
+
+ return prop->set(ebi, prop, cs, setup);
+}
+
+static void stm32_fmc2_ebi_enable_bank(struct stm32_fmc2_ebi *ebi, int cs)
+{
+ setbits_le32(ebi->io_base + FMC2_BCR(cs), FMC2_BCR_MBKEN);
+}
+
+static void stm32_fmc2_ebi_disable_bank(struct stm32_fmc2_ebi *ebi, int cs)
+{
+ clrbits_le32(ebi->io_base + FMC2_BCR(cs), FMC2_BCR_MBKEN);
+}
+
+/* NWAIT signal can not be connected to EBI controller and NAND controller */
+static bool stm32_fmc2_ebi_nwait_used_by_ctrls(struct stm32_fmc2_ebi *ebi)
+{
+ unsigned int cs;
+ u32 bcr;
+
+ for (cs = 0; cs < FMC2_MAX_EBI_CE; cs++) {
+ if (!(ebi->bank_assigned & BIT(cs)))
+ continue;
+
+ bcr = readl(ebi->io_base + FMC2_BCR(cs));
+ if ((bcr & FMC2_BCR_WAITEN || bcr & FMC2_BCR_ASYNCWAIT) &&
+ ebi->bank_assigned & BIT(FMC2_NAND))
+ return true;
+ }
+
+ return false;
+}
+
+static void stm32_fmc2_ebi_enable(struct stm32_fmc2_ebi *ebi)
+{
+ setbits_le32(ebi->io_base + FMC2_BCR1, FMC2_BCR1_FMC2EN);
+}
+
+static int stm32_fmc2_ebi_setup_cs(struct stm32_fmc2_ebi *ebi,
+ struct device_node *node, u32 cs)
+{
+ unsigned int i;
+ int ret;
+
+ stm32_fmc2_ebi_disable_bank(ebi, cs);
+
+ 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(ebi, node, p, cs);
+ if (ret) {
+ pr_err("property %s could not be set: %d\n", p->name, ret);
+ return ret;
+ }
+ }
+
+ stm32_fmc2_ebi_enable_bank(ebi, cs);
+
+ 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 bank;
+ int ret;
+
+ for_each_available_child_of_node(dev->of_node, child) {
+ ret = of_property_read_u32(child, "reg", &bank);
+ if (ret) {
+ dev_err(dev, "could not retrieve reg property: %d\n", ret);
+ return ret;
+ }
+
+ if (bank >= FMC2_MAX_BANKS) {
+ dev_err(dev, "invalid reg value: %d\n", bank);
+ return -EINVAL;
+ }
+
+ if (ebi->bank_assigned & BIT(bank)) {
+ dev_err(dev, "bank already assigned: %d\n", bank);
+ return -EINVAL;
+ }
+
+ if (bank < FMC2_MAX_EBI_CE) {
+ ret = stm32_fmc2_ebi_setup_cs(ebi, child, bank);
+ if (ret) {
+ dev_err(dev, "setup chip select %d failed: %d\n", bank, ret);
+ return ret;
+ }
+ }
+
+ ebi->bank_assigned |= BIT(bank);
+ child_found = true;
+ }
+
+ if (!child_found) {
+ dev_warn(dev, "no subnodes found.\n");
+ return -ENODEV;
+ }
+
+ if (stm32_fmc2_ebi_nwait_used_by_ctrls(ebi)) {
+ dev_err(dev, "NWAIT signal connected to EBI and NAND controllers\n");
+ return -EINVAL;
+ }
+
+ stm32_fmc2_ebi_enable(ebi);
+
+ return 0;
+}
+
+static int __init stm32_fmc2_ebi_probe(struct device *dev)
+{
+ struct stm32_fmc2_ebi *ebi;
+ int ret;
+
+ ebi = xzalloc(sizeof(*ebi));
+
+ ebi->clk = clk_get(dev, NULL);
+ if (IS_ERR(ebi->clk)) {
+ ret = PTR_ERR(ebi->clk);
+ goto out_kfree;
+ }
+
+ clk_enable(ebi->clk);
+
+ ebi->io_base = of_iomap(dev->of_node, 0);
+ if (!ebi->io_base) {
+ ret = -ENOMEM;
+ goto out_clk;
+ }
+
+ ret = device_reset_us(dev, 2);
+ if (ret)
+ goto out_clk;
+
+ ret = stm32_fmc2_ebi_parse_dt(dev, ebi);
+ if (ret)
+ goto out_clk;
+
+ return of_platform_populate(dev->of_node, NULL, dev);
+
+out_clk:
+ clk_disable(ebi->clk);
+
+out_kfree:
+ kfree(ebi);
+
+ return ret;
+}
+
+static __maybe_unused struct of_device_id stm32_fmc2_ebi_dt_ids[] = {
+ { .compatible = "st,stm32mp1-fmc2-ebi", },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, stm32_fmc2_ebi_dt_ids);
+
+static struct driver stm32_fmc2_ebi_driver = {
+ .name = "stm32_fmc2_ebi",
+ .probe = stm32_fmc2_ebi_probe,
+ .of_compatible = DRV_OF_COMPAT(stm32_fmc2_ebi_dt_ids),
+};
+coredevice_platform_driver(stm32_fmc2_ebi_driver);
--
2.39.1
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