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Message-ID: <20230403183217.13280-3-mmkurbanov@sberdevices.ru>
Date: Mon, 3 Apr 2023 21:32:17 +0300
From: Martin Kurbanov <mmkurbanov@...rdevices.ru>
To: Mark Brown <broonie@...nel.org>, Rob Herring <robh+dt@...nel.org>,
Krzysztof Kozlowski <krzysztof.kozlowski+dt@...aro.org>,
Neil Armstrong <neil.armstrong@...aro.org>,
Kevin Hilman <khilman@...libre.com>,
Jerome Brunet <jbrunet@...libre.com>,
Martin Blumenstingl <martin.blumenstingl@...glemail.com>
CC: <linux-spi@...r.kernel.org>, <devicetree@...r.kernel.org>,
<linux-arm-kernel@...ts.infradead.org>,
<linux-amlogic@...ts.infradead.org>,
<linux-kernel@...r.kernel.org>, <kernel@...rdevices.ru>,
Martin Kurbanov <mmkurbanov@...rdevices.ru>
Subject: [PATCH v3 2/2] spi: add support for Amlogic A1 SPI Flash Controller
This is a driver for the Amlogic SPI flash controller support
on A113L SoC.
Signed-off-by: Martin Kurbanov <mmkurbanov@...rdevices.ru>
---
drivers/spi/Kconfig | 7 +
drivers/spi/Makefile | 1 +
drivers/spi/spi-amlogic-spifc-a1.c | 456 +++++++++++++++++++++++++++++
3 files changed, 464 insertions(+)
create mode 100644 drivers/spi/spi-amlogic-spifc-a1.c
diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
index 3b1c0878bb85..af507887fdaf 100644
--- a/drivers/spi/Kconfig
+++ b/drivers/spi/Kconfig
@@ -79,6 +79,13 @@ config SPI_ALTERA_DFL
Altera SPI master controller. The SPI master is connected
to a SPI slave to Avalon bridge in a Intel MAX BMC.
+config SPI_AMLOGIC_SPIFC_A1
+ tristate "Amlogic A1 SPIFC controller"
+ depends on ARCH_MESON || COMPILE_TEST
+ help
+ This enables master mode support for the SPIFC (SPI flash
+ controller) available in Amlogic A1 (A113L SoC).
+
config SPI_AR934X
tristate "Qualcomm Atheros AR934X/QCA95XX SPI controller driver"
depends on ATH79 || COMPILE_TEST
diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile
index be9ba40ef8d0..f61670ed1fc7 100644
--- a/drivers/spi/Makefile
+++ b/drivers/spi/Makefile
@@ -17,6 +17,7 @@ obj-$(CONFIG_SPI_LOOPBACK_TEST) += spi-loopback-test.o
obj-$(CONFIG_SPI_ALTERA) += spi-altera-platform.o
obj-$(CONFIG_SPI_ALTERA_CORE) += spi-altera-core.o
obj-$(CONFIG_SPI_ALTERA_DFL) += spi-altera-dfl.o
+obj-$(CONFIG_SPI_AMLOGIC_SPIFC_A1) += spi-amlogic-spifc-a1.o
obj-$(CONFIG_SPI_AR934X) += spi-ar934x.o
obj-$(CONFIG_SPI_ARMADA_3700) += spi-armada-3700.o
obj-$(CONFIG_SPI_ASPEED_SMC) += spi-aspeed-smc.o
diff --git a/drivers/spi/spi-amlogic-spifc-a1.c b/drivers/spi/spi-amlogic-spifc-a1.c
new file mode 100644
index 000000000000..3c4224c38399
--- /dev/null
+++ b/drivers/spi/spi-amlogic-spifc-a1.c
@@ -0,0 +1,456 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Driver for Amlogic A1 SPI flash controller (SPIFC)
+ *
+ * Copyright (c) 2023, SberDevices. All Rights Reserved.
+ *
+ * Author: Martin Kurbanov <mmkurbanov@...rdevices.ru>
+ */
+
+#include <linux/bitfield.h>
+#include <linux/clk.h>
+#include <linux/device.h>
+#include <linux/io.h>
+#include <linux/iopoll.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/spi/spi.h>
+#include <linux/spi/spi-mem.h>
+#include <linux/types.h>
+
+#define SPIFC_A1_AHB_CTRL_REG 0x0
+#define SPIFC_A1_AHB_BUS_EN BIT(31)
+
+#define SPIFC_A1_USER_CTRL0_REG 0x200
+#define SPIFC_A1_USER_REQUEST_ENABLE BIT(31)
+#define SPIFC_A1_USER_REQUEST_FINISH BIT(30)
+#define SPIFC_A1_USER_DATA_UPDATED BIT(0)
+
+#define SPIFC_A1_USER_CTRL1_REG 0x204
+#define SPIFC_A1_USER_CMD_ENABLE BIT(30)
+#define SPIFC_A1_USER_CMD_MODE GENMASK(29, 28)
+#define SPIFC_A1_USER_CMD_CODE GENMASK(27, 20)
+#define SPIFC_A1_USER_ADDR_ENABLE BIT(19)
+#define SPIFC_A1_USER_ADDR_MODE GENMASK(18, 17)
+#define SPIFC_A1_USER_ADDR_BYTES GENMASK(16, 15)
+#define SPIFC_A1_USER_DOUT_ENABLE BIT(14)
+#define SPIFC_A1_USER_DOUT_MODE GENMASK(11, 10)
+#define SPIFC_A1_USER_DOUT_BYTES GENMASK(9, 0)
+
+#define SPIFC_A1_USER_CTRL2_REG 0x208
+#define SPIFC_A1_USER_DUMMY_ENABLE BIT(31)
+#define SPIFC_A1_USER_DUMMY_MODE GENMASK(30, 29)
+#define SPIFC_A1_USER_DUMMY_CLK_SYCLES GENMASK(28, 23)
+
+#define SPIFC_A1_USER_CTRL3_REG 0x20c
+#define SPIFC_A1_USER_DIN_ENABLE BIT(31)
+#define SPIFC_A1_USER_DIN_MODE GENMASK(28, 27)
+#define SPIFC_A1_USER_DIN_BYTES GENMASK(25, 16)
+
+#define SPIFC_A1_USER_ADDR_REG 0x210
+
+#define SPIFC_A1_AHB_REQ_CTRL_REG 0x214
+#define SPIFC_A1_AHB_REQ_ENABLE BIT(31)
+
+#define SPIFC_A1_ACTIMING0_REG (0x0088 << 2)
+#define SPIFC_A1_TSLCH GENMASK(31, 30)
+#define SPIFC_A1_TCLSH GENMASK(29, 28)
+#define SPIFC_A1_TSHWL GENMASK(20, 16)
+#define SPIFC_A1_TSHSL2 GENMASK(15, 12)
+#define SPIFC_A1_TSHSL1 GENMASK(11, 8)
+#define SPIFC_A1_TWHSL GENMASK(7, 0)
+
+#define SPIFC_A1_DBUF_CTRL_REG 0x240
+#define SPIFC_A1_DBUF_DIR BIT(31)
+#define SPIFC_A1_DBUF_AUTO_UPDATE_ADDR BIT(30)
+#define SPIFC_A1_DBUF_ADDR GENMASK(7, 0)
+
+#define SPIFC_A1_DBUF_DATA_REG 0x244
+
+#define SPIFC_A1_USER_DBUF_ADDR_REG 0x248
+
+#define SPIFC_A1_BUFFER_SIZE 512
+
+#define SPIFC_A1_MAX_HZ 200000000
+#define SPIFC_A1_MIN_HZ 1000000
+
+#define SPIFC_A1_USER_CMD(op) ( \
+ SPIFC_A1_USER_CMD_ENABLE | \
+ FIELD_PREP(SPIFC_A1_USER_CMD_CODE, (op)->cmd.opcode) | \
+ FIELD_PREP(SPIFC_A1_USER_CMD_MODE, ilog2((op)->cmd.buswidth)))
+
+#define SPIFC_A1_USER_ADDR(op) ( \
+ SPIFC_A1_USER_ADDR_ENABLE | \
+ FIELD_PREP(SPIFC_A1_USER_ADDR_MODE, ilog2((op)->addr.buswidth)) | \
+ FIELD_PREP(SPIFC_A1_USER_ADDR_BYTES, (op)->addr.nbytes - 1))
+
+#define SPIFC_A1_USER_DUMMY(op) ( \
+ SPIFC_A1_USER_DUMMY_ENABLE | \
+ FIELD_PREP(SPIFC_A1_USER_DUMMY_MODE, ilog2((op)->dummy.buswidth)) | \
+ FIELD_PREP(SPIFC_A1_USER_DUMMY_CLK_SYCLES, (op)->dummy.nbytes << 3))
+
+#define SPIFC_A1_TSLCH_VAL FIELD_PREP(SPIFC_A1_TSLCH, 1)
+#define SPIFC_A1_TCLSH_VAL FIELD_PREP(SPIFC_A1_TCLSH, 1)
+#define SPIFC_A1_TSHWL_VAL FIELD_PREP(SPIFC_A1_TSHWL, 7)
+#define SPIFC_A1_TSHSL2_VAL FIELD_PREP(SPIFC_A1_TSHSL2, 7)
+#define SPIFC_A1_TSHSL1_VAL FIELD_PREP(SPIFC_A1_TSHSL1, 7)
+#define SPIFC_A1_TWHSL_VAL FIELD_PREP(SPIFC_A1_TWHSL, 2)
+#define SPIFC_A1_ACTIMING0_VAL (SPIFC_A1_TSLCH_VAL | SPIFC_A1_TCLSH_VAL | \
+ SPIFC_A1_TSHWL_VAL | SPIFC_A1_TSHSL2_VAL | \
+ SPIFC_A1_TSHSL1_VAL | SPIFC_A1_TWHSL_VAL)
+
+struct amlogic_spifc_a1 {
+ struct spi_controller *ctrl;
+ struct clk *clk;
+ struct device *dev;
+ void __iomem *base;
+};
+
+static int amlogic_spifc_a1_request(struct amlogic_spifc_a1 *spifc, bool read)
+{
+ u32 mask = SPIFC_A1_USER_REQUEST_FINISH |
+ (read ? SPIFC_A1_USER_DATA_UPDATED : 0);
+ u32 val;
+
+ writel(SPIFC_A1_USER_REQUEST_ENABLE,
+ spifc->base + SPIFC_A1_USER_CTRL0_REG);
+
+ return readl_poll_timeout(spifc->base + SPIFC_A1_USER_CTRL0_REG,
+ val, (val & mask) == mask, 0,
+ 200 * USEC_PER_MSEC);
+}
+
+static void amlogic_spifc_a1_drain_buffer(struct amlogic_spifc_a1 *spifc,
+ char *buf, u32 len)
+{
+ u32 data;
+ const u32 count = len / sizeof(data);
+ const u32 pad = len % sizeof(data);
+
+ writel(SPIFC_A1_DBUF_AUTO_UPDATE_ADDR,
+ spifc->base + SPIFC_A1_DBUF_CTRL_REG);
+ ioread32_rep(spifc->base + SPIFC_A1_DBUF_DATA_REG, buf, count);
+
+ if (pad) {
+ data = readl(spifc->base + SPIFC_A1_DBUF_DATA_REG);
+ memcpy(buf + len - pad, &data, pad);
+ }
+}
+
+static void amlogic_spifc_a1_fill_buffer(struct amlogic_spifc_a1 *spifc,
+ const char *buf, u32 len)
+{
+ u32 data;
+ const u32 count = len / sizeof(data);
+ const u32 pad = len % sizeof(data);
+
+ writel(SPIFC_A1_DBUF_DIR | SPIFC_A1_DBUF_AUTO_UPDATE_ADDR,
+ spifc->base + SPIFC_A1_DBUF_CTRL_REG);
+ iowrite32_rep(spifc->base + SPIFC_A1_DBUF_DATA_REG, buf, count);
+
+ if (pad) {
+ memcpy(&data, buf + len - pad, pad);
+ writel(data, spifc->base + SPIFC_A1_DBUF_DATA_REG);
+ }
+}
+
+static void amlogic_spifc_a1_user_init(struct amlogic_spifc_a1 *spifc)
+{
+ writel(0, spifc->base + SPIFC_A1_USER_CTRL0_REG);
+ writel(0, spifc->base + SPIFC_A1_USER_CTRL1_REG);
+ writel(0, spifc->base + SPIFC_A1_USER_CTRL2_REG);
+ writel(0, spifc->base + SPIFC_A1_USER_CTRL3_REG);
+}
+
+static void amlogic_spifc_a1_set_cmd(struct amlogic_spifc_a1 *spifc,
+ u32 cmd_cfg)
+{
+ u32 val;
+
+ val = readl(spifc->base + SPIFC_A1_USER_CTRL1_REG);
+ val &= ~(SPIFC_A1_USER_CMD_MODE | SPIFC_A1_USER_CMD_CODE);
+ val |= cmd_cfg;
+ writel(val, spifc->base + SPIFC_A1_USER_CTRL1_REG);
+}
+
+static void amlogic_spifc_a1_set_addr(struct amlogic_spifc_a1 *spifc, u32 addr,
+ u32 addr_cfg)
+{
+ u32 val;
+
+ writel(addr, spifc->base + SPIFC_A1_USER_ADDR_REG);
+
+ val = readl(spifc->base + SPIFC_A1_USER_CTRL1_REG);
+ val &= ~(SPIFC_A1_USER_ADDR_MODE | SPIFC_A1_USER_ADDR_BYTES);
+ val |= addr_cfg;
+ writel(val, spifc->base + SPIFC_A1_USER_CTRL1_REG);
+}
+
+static void amlogic_spifc_a1_set_dummy(struct amlogic_spifc_a1 *spifc,
+ u32 dummy_cfg)
+{
+ u32 val = readl(spifc->base + SPIFC_A1_USER_CTRL2_REG);
+
+ val &= ~(SPIFC_A1_USER_DUMMY_MODE | SPIFC_A1_USER_DUMMY_CLK_SYCLES);
+ val |= dummy_cfg;
+ writel(val, spifc->base + SPIFC_A1_USER_CTRL2_REG);
+}
+
+static int amlogic_spifc_a1_read(struct amlogic_spifc_a1 *spifc, void *buf,
+ u32 size, u32 mode)
+{
+ u32 val = readl(spifc->base + SPIFC_A1_USER_CTRL3_REG);
+ int ret;
+
+ val &= ~(SPIFC_A1_USER_DIN_MODE | SPIFC_A1_USER_DIN_BYTES);
+ val |= SPIFC_A1_USER_DIN_ENABLE;
+ val |= FIELD_PREP(SPIFC_A1_USER_DIN_MODE, mode);
+ val |= FIELD_PREP(SPIFC_A1_USER_DIN_BYTES, size);
+ writel(val, spifc->base + SPIFC_A1_USER_CTRL3_REG);
+
+ ret = amlogic_spifc_a1_request(spifc, true);
+ if (!ret)
+ amlogic_spifc_a1_drain_buffer(spifc, buf, size);
+
+ return ret;
+}
+
+static int amlogic_spifc_a1_write(struct amlogic_spifc_a1 *spifc,
+ const void *buf, u32 size, u32 mode)
+{
+ u32 val;
+
+ amlogic_spifc_a1_fill_buffer(spifc, buf, size);
+
+ val = readl(spifc->base + SPIFC_A1_USER_CTRL1_REG);
+ val &= ~(SPIFC_A1_USER_DOUT_MODE | SPIFC_A1_USER_DOUT_BYTES);
+ val |= FIELD_PREP(SPIFC_A1_USER_DOUT_MODE, mode);
+ val |= FIELD_PREP(SPIFC_A1_USER_DOUT_BYTES, size);
+ val |= SPIFC_A1_USER_DOUT_ENABLE;
+ writel(val, spifc->base + SPIFC_A1_USER_CTRL1_REG);
+
+ return amlogic_spifc_a1_request(spifc, false);
+}
+
+static int amlogic_spifc_a1_exec_op(struct spi_mem *mem,
+ const struct spi_mem_op *op)
+{
+ struct amlogic_spifc_a1 *spifc =
+ spi_controller_get_devdata(mem->spi->controller);
+ size_t off, nbytes = op->data.nbytes;
+ u32 cmd_cfg, addr_cfg, dummy_cfg, dmode;
+ int ret;
+
+ amlogic_spifc_a1_user_init(spifc);
+
+ cmd_cfg = SPIFC_A1_USER_CMD(op);
+ amlogic_spifc_a1_set_cmd(spifc, cmd_cfg);
+
+ if (op->addr.nbytes) {
+ addr_cfg = SPIFC_A1_USER_ADDR(op);
+ amlogic_spifc_a1_set_addr(spifc, op->addr.val, addr_cfg);
+ }
+
+ if (op->dummy.nbytes) {
+ dummy_cfg = SPIFC_A1_USER_DUMMY(op);
+ amlogic_spifc_a1_set_dummy(spifc, dummy_cfg);
+ }
+
+ if (!op->data.nbytes)
+ return amlogic_spifc_a1_request(spifc, false);
+
+ dmode = ilog2(op->data.buswidth);
+ off = 0;
+
+ do {
+ size_t block_size = min_t(size_t, nbytes, SPIFC_A1_BUFFER_SIZE);
+
+ amlogic_spifc_a1_set_cmd(spifc, cmd_cfg);
+
+ if (op->addr.nbytes)
+ amlogic_spifc_a1_set_addr(spifc, op->addr.val + off,
+ addr_cfg);
+
+ if (op->dummy.nbytes)
+ amlogic_spifc_a1_set_dummy(spifc, dummy_cfg);
+
+ writel(0, spifc->base + SPIFC_A1_USER_DBUF_ADDR_REG);
+
+ if (op->data.dir == SPI_MEM_DATA_IN)
+ ret = amlogic_spifc_a1_read(spifc,
+ op->data.buf.in + off,
+ block_size, dmode);
+ else
+ ret = amlogic_spifc_a1_write(spifc,
+ op->data.buf.out + off,
+ block_size, dmode);
+
+ nbytes -= block_size;
+ off += block_size;
+ } while (nbytes != 0 && !ret);
+
+ return ret;
+}
+
+static void amlogic_spifc_a1_hw_init(struct amlogic_spifc_a1 *spifc)
+{
+ u32 regv;
+
+ regv = readl(spifc->base + SPIFC_A1_AHB_REQ_CTRL_REG);
+ regv &= ~(SPIFC_A1_AHB_REQ_ENABLE);
+ writel(regv, spifc->base + SPIFC_A1_AHB_REQ_CTRL_REG);
+
+ regv = readl(spifc->base + SPIFC_A1_AHB_CTRL_REG);
+ regv &= ~(SPIFC_A1_AHB_BUS_EN);
+ writel(regv, spifc->base + SPIFC_A1_AHB_CTRL_REG);
+
+ writel(SPIFC_A1_ACTIMING0_VAL, spifc->base + SPIFC_A1_ACTIMING0_REG);
+
+ writel(0, spifc->base + SPIFC_A1_USER_DBUF_ADDR_REG);
+}
+
+static const struct spi_controller_mem_ops amlogic_spifc_a1_mem_ops = {
+ .exec_op = amlogic_spifc_a1_exec_op,
+};
+
+static int amlogic_spifc_a1_probe(struct platform_device *pdev)
+{
+ struct spi_controller *ctrl;
+ struct amlogic_spifc_a1 *spifc;
+ int ret;
+
+ ctrl = devm_spi_alloc_master(&pdev->dev, sizeof(*spifc));
+ if (!ctrl)
+ return -ENOMEM;
+
+ spifc = spi_controller_get_devdata(ctrl);
+ platform_set_drvdata(pdev, spifc);
+
+ spifc->dev = &pdev->dev;
+ spifc->ctrl = ctrl;
+
+ spifc->base = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(spifc->base))
+ return PTR_ERR(spifc->base);
+
+ spifc->clk = devm_clk_get_enabled(spifc->dev, NULL);
+ if (IS_ERR(spifc->clk))
+ return dev_err_probe(spifc->dev, PTR_ERR(spifc->clk),
+ "unable to get clock\n");
+
+ amlogic_spifc_a1_hw_init(spifc);
+
+ pm_runtime_set_autosuspend_delay(spifc->dev, 500);
+ pm_runtime_use_autosuspend(spifc->dev);
+ devm_pm_runtime_enable(spifc->dev);
+
+ ctrl->num_chipselect = 1;
+ ctrl->dev.of_node = pdev->dev.of_node;
+ ctrl->bits_per_word_mask = SPI_BPW_MASK(8);
+ ctrl->auto_runtime_pm = true;
+ ctrl->mem_ops = &amlogic_spifc_a1_mem_ops;
+ ctrl->min_speed_hz = SPIFC_A1_MIN_HZ;
+ ctrl->max_speed_hz = SPIFC_A1_MAX_HZ;
+ ctrl->mode_bits = (SPI_RX_DUAL | SPI_TX_DUAL |
+ SPI_RX_QUAD | SPI_TX_QUAD);
+
+ ret = devm_spi_register_controller(spifc->dev, ctrl);
+ if (ret)
+ return dev_err_probe(spifc->dev, ret,
+ "failed to register spi controller\n");
+
+ return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int amlogic_spifc_a1_suspend(struct device *dev)
+{
+ struct amlogic_spifc_a1 *spifc = dev_get_drvdata(dev);
+ int ret;
+
+ ret = spi_controller_suspend(spifc->ctrl);
+ if (ret)
+ return ret;
+
+ if (!pm_runtime_suspended(dev))
+ clk_disable_unprepare(spifc->clk);
+
+ return 0;
+}
+
+static int amlogic_spifc_a1_resume(struct device *dev)
+{
+ struct amlogic_spifc_a1 *spifc = dev_get_drvdata(dev);
+ int ret = 0;
+
+ if (!pm_runtime_suspended(dev)) {
+ ret = clk_prepare_enable(spifc->clk);
+ if (ret)
+ return ret;
+ }
+
+ amlogic_spifc_a1_hw_init(spifc);
+
+ ret = spi_controller_resume(spifc->ctrl);
+ if (ret)
+ clk_disable_unprepare(spifc->clk);
+
+ return ret;
+}
+#endif /* CONFIG_PM_SLEEP */
+
+#ifdef CONFIG_PM
+static int amlogic_spifc_a1_runtime_suspend(struct device *dev)
+{
+ struct amlogic_spifc_a1 *spifc = dev_get_drvdata(dev);
+
+ clk_disable_unprepare(spifc->clk);
+
+ return 0;
+}
+
+static int amlogic_spifc_a1_runtime_resume(struct device *dev)
+{
+ struct amlogic_spifc_a1 *spifc = dev_get_drvdata(dev);
+ int ret;
+
+ ret = clk_prepare_enable(spifc->clk);
+ if (!ret)
+ amlogic_spifc_a1_hw_init(spifc);
+
+ return ret;
+}
+#endif /* CONFIG_PM */
+
+static const struct dev_pm_ops amlogic_spifc_a1_pm_ops = {
+ SET_SYSTEM_SLEEP_PM_OPS(amlogic_spifc_a1_suspend,
+ amlogic_spifc_a1_resume)
+ SET_RUNTIME_PM_OPS(amlogic_spifc_a1_runtime_suspend,
+ amlogic_spifc_a1_runtime_resume,
+ NULL)
+};
+
+#ifdef CONFIG_OF
+static const struct of_device_id amlogic_spifc_a1_dt_match[] = {
+ { .compatible = "amlogic,a1-spifc", },
+ { },
+};
+MODULE_DEVICE_TABLE(of, amlogic_spifc_a1_dt_match);
+#endif /* CONFIG_OF */
+
+static struct platform_driver amlogic_spifc_a1_driver = {
+ .probe = amlogic_spifc_a1_probe,
+ .driver = {
+ .name = "amlogic-spifc-a1",
+ .of_match_table = of_match_ptr(amlogic_spifc_a1_dt_match),
+ .pm = &amlogic_spifc_a1_pm_ops,
+ },
+};
+module_platform_driver(amlogic_spifc_a1_driver);
+
+MODULE_AUTHOR("Martin Kurbanov <mmkurbanov@...rdevices.ru>");
+MODULE_DESCRIPTION("Amlogic A1 SPIFC driver");
+MODULE_LICENSE("GPL");
--
2.37.2
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