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Message-Id: <20220824150114.17504-2-i.bornyakov@metrotek.ru>
Date: Wed, 24 Aug 2022 18:01:13 +0300
From: Ivan Bornyakov <i.bornyakov@...rotek.ru>
To: mdf@...nel.org, hao.wu@...el.com, yilun.xu@...el.com,
trix@...hat.com, dg@...ix.com, robh+dt@...nel.org,
krzysztof.kozlowski+dt@...aro.org
Cc: Ivan Bornyakov <i.bornyakov@...rotek.ru>,
linux-fpga@...r.kernel.org, devicetree@...r.kernel.org,
linux-kernel@...r.kernel.org, system@...rotek.ru
Subject: [PATCH v7 1/2] fpga: lattice-sysconfig-spi: add Lattice sysCONFIG FPGA manager
Add support to the FPGA manager for programming Lattice ECP5 and MachXO2
FPGAs over slave SPI sysCONFIG interface.
Signed-off-by: Ivan Bornyakov <i.bornyakov@...rotek.ru>
---
drivers/fpga/Kconfig | 7 +
drivers/fpga/Makefile | 1 +
drivers/fpga/lattice-sysconfig-spi.c | 630 +++++++++++++++++++++++++++
3 files changed, 638 insertions(+)
create mode 100644 drivers/fpga/lattice-sysconfig-spi.c
diff --git a/drivers/fpga/Kconfig b/drivers/fpga/Kconfig
index 6c416955da53..991d9d976dca 100644
--- a/drivers/fpga/Kconfig
+++ b/drivers/fpga/Kconfig
@@ -263,4 +263,11 @@ config FPGA_MGR_MICROCHIP_SPI
programming over slave SPI interface with .dat formatted
bitstream image.
+config FPGA_MGR_LATTICE_SPI
+ tristate "Lattice sysCONFIG SPI FPGA manager"
+ depends on SPI
+ help
+ FPGA manager driver support for Lattice FPGAs programming over slave
+ SPI sysCONFIG interface.
+
endif # FPGA
diff --git a/drivers/fpga/Makefile b/drivers/fpga/Makefile
index 42ae8b58abce..115dba916024 100644
--- a/drivers/fpga/Makefile
+++ b/drivers/fpga/Makefile
@@ -20,6 +20,7 @@ obj-$(CONFIG_FPGA_MGR_ZYNQ_FPGA) += zynq-fpga.o
obj-$(CONFIG_FPGA_MGR_ZYNQMP_FPGA) += zynqmp-fpga.o
obj-$(CONFIG_FPGA_MGR_VERSAL_FPGA) += versal-fpga.o
obj-$(CONFIG_FPGA_MGR_MICROCHIP_SPI) += microchip-spi.o
+obj-$(CONFIG_FPGA_MGR_LATTICE_SPI) += lattice-sysconfig-spi.o
obj-$(CONFIG_ALTERA_PR_IP_CORE) += altera-pr-ip-core.o
obj-$(CONFIG_ALTERA_PR_IP_CORE_PLAT) += altera-pr-ip-core-plat.o
diff --git a/drivers/fpga/lattice-sysconfig-spi.c b/drivers/fpga/lattice-sysconfig-spi.c
new file mode 100644
index 000000000000..145b5b27b88d
--- /dev/null
+++ b/drivers/fpga/lattice-sysconfig-spi.c
@@ -0,0 +1,630 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Lattice FPGA programming over slave SPI sysCONFIG interface.
+ */
+
+#include <linux/delay.h>
+#include <linux/fpga/fpga-mgr.h>
+#include <linux/of_device.h>
+#include <linux/spi/spi.h>
+
+#define SYSCONFIG_ISC_ENABLE {0xC6, 0x00, 0x00, 0x00}
+#define SYSCONFIG_ISC_DISABLE {0x26, 0x00, 0x00, 0x00}
+#define SYSCONFIG_ISC_ERASE {0x0E, 0x00, 0x00, 0x00}
+#define SYSCONFIG_ISC_PROGRAM_DONE {0x5E, 0x00, 0x00, 0x00}
+#define SYSCONFIG_LSC_READ_STATUS {0x3C, 0x00, 0x00, 0x00}
+#define SYSCONFIG_LSC_CHECK_BUSY {0xF0, 0x00, 0x00, 0x00}
+#define SYSCONFIG_LSC_REFRESH {0x79, 0x00, 0x00, 0x00}
+#define SYSCONFIG_LSC_INIT_ADDR {0x46, 0x00, 0x00, 0x00}
+#define SYSCONFIG_LSC_BITSTREAM_BURST {0x7a, 0x00, 0x00, 0x00}
+#define SYSCONFIG_LSC_PROG_INCR_NV {0x70, 0x00, 0x00, 0x01}
+
+#define SYSCONFIG_STATUS_DONE BIT(8)
+#define SYSCONFIG_STATUS_BUSY BIT(12)
+#define SYSCONFIG_STATUS_FAIL BIT(13)
+#define SYSCONFIG_STATUS_ERR (BIT(23) | BIT(24) | BIT(25))
+
+#define SYSCONFIG_POLL_RETRIES 100000
+
+#define ECP5_SPI_MAX_SPEED_HZ 60000000
+#define ECP5_ISC_ERASE_OPERAND 0x01
+
+#define MACHXO2_SPI_MAX_SPEED_HZ 66000000
+#define MACHXO2_PAGE_SIZE 16
+#define MACHXO2_ISC_ENABLE_OPERAND 0x08
+#define MACHXO2_ISC_ERASE_OPERAND 0x04
+
+struct sysconfig_priv {
+ struct gpio_desc *program;
+ struct gpio_desc *init;
+ struct gpio_desc *done;
+ struct spi_device *spi;
+ u8 isc_enable_operand;
+ u8 isc_erase_operand;
+};
+
+static int sysconfig_poll_busy(struct sysconfig_priv *data)
+{
+ const u8 lsc_check_busy[] = SYSCONFIG_LSC_CHECK_BUSY;
+ int ret, retries = SYSCONFIG_POLL_RETRIES;
+ u8 busy;
+
+ while (retries--) {
+ ret = spi_write_then_read(data->spi,
+ lsc_check_busy, sizeof(lsc_check_busy),
+ &busy, sizeof(busy));
+ if (ret)
+ return ret;
+
+ if (!busy)
+ return 0;
+
+ usleep_range(50, 100);
+ }
+
+ return -EBUSY;
+}
+
+static int sysconfig_read_status(struct sysconfig_priv *data, u32 *status)
+{
+ const u8 lsc_read_status[] = SYSCONFIG_LSC_READ_STATUS;
+ __be32 device_status;
+ int ret;
+
+ ret = spi_write_then_read(data->spi,
+ lsc_read_status, sizeof(lsc_read_status),
+ &device_status, sizeof(device_status));
+ if (ret)
+ return ret;
+
+ *status = be32_to_cpu(device_status);
+
+ return 0;
+}
+
+static int sysconfig_poll_status(struct sysconfig_priv *data, u32 *status)
+{
+ int ret;
+
+ ret = sysconfig_poll_busy(data);
+ if (ret)
+ return ret;
+
+ return sysconfig_read_status(data, status);
+}
+
+static int sysconfig_poll_gpio(struct gpio_desc *gpio, bool is_active)
+{
+ int value, retries = SYSCONFIG_POLL_RETRIES;
+
+ while (retries--) {
+ value = gpiod_get_value(gpio);
+ if (value < 0)
+ return value;
+
+ if ((!is_active && !value) || (is_active && value))
+ return 0;
+
+ ndelay(10);
+ }
+
+ return -ETIMEDOUT;
+}
+
+static int sysconfig_refresh(struct sysconfig_priv *data)
+{
+ static const u8 lsc_refresh[] = SYSCONFIG_LSC_REFRESH;
+ int ret;
+
+ ret = spi_write(data->spi, lsc_refresh, sizeof(lsc_refresh));
+ if (ret)
+ return ret;
+
+ usleep_range(4000, 8000);
+
+ return 0;
+}
+
+static int sysconfig_isc_enable(struct sysconfig_priv *data)
+{
+ u8 isc_enable[] = SYSCONFIG_ISC_ENABLE;
+ u32 status;
+ int ret;
+
+ isc_enable[1] = data->isc_enable_operand;
+
+ ret = spi_write(data->spi, isc_enable, sizeof(isc_enable));
+ if (ret)
+ return ret;
+
+ ret = sysconfig_poll_status(data, &status);
+ if (ret || (status & SYSCONFIG_STATUS_FAIL))
+ return ret ? : -EFAULT;
+
+ return 0;
+}
+
+static int sysconfig_isc_erase(struct sysconfig_priv *data)
+{
+ u8 isc_erase[] = SYSCONFIG_ISC_ERASE;
+ u32 status;
+ int ret;
+
+ isc_erase[1] = data->isc_erase_operand;
+
+ ret = spi_write(data->spi, isc_erase, sizeof(isc_erase));
+ if (ret)
+ return ret;
+
+ ret = sysconfig_poll_status(data, &status);
+ if (ret || (status & SYSCONFIG_STATUS_FAIL))
+ return ret ? : -EFAULT;
+
+ return 0;
+}
+
+static int sysconfig_isc_init(struct sysconfig_priv *data)
+{
+ int ret;
+
+ ret = sysconfig_isc_enable(data);
+ if (ret)
+ return ret;
+
+ return sysconfig_isc_erase(data);
+}
+
+static int sysconfig_lsc_init_addr(struct sysconfig_priv *data)
+{
+ const u8 lsc_init_addr[] = SYSCONFIG_LSC_INIT_ADDR;
+
+ return spi_write(data->spi, lsc_init_addr, sizeof(lsc_init_addr));
+}
+
+static int sysconfig_lsc_bitstream_burst(struct sysconfig_priv *data)
+{
+ const u8 lsc_bitstream_burst[] = SYSCONFIG_LSC_BITSTREAM_BURST;
+ struct spi_transfer xfer = {
+ .tx_buf = lsc_bitstream_burst,
+ .len = sizeof(lsc_bitstream_burst),
+ .cs_change = 1,
+ };
+ struct spi_message msg;
+
+ spi_message_init_with_transfers(&msg, &xfer, 1);
+
+ return spi_sync_locked(data->spi, &msg);
+}
+
+static int sysconfig_isc_prog_done(struct sysconfig_priv *data)
+{
+ const u8 isc_prog_done[] = SYSCONFIG_ISC_PROGRAM_DONE;
+ u32 status;
+ int ret;
+
+ ret = spi_write(data->spi, isc_prog_done, sizeof(isc_prog_done));
+ if (ret)
+ return ret;
+
+ ret = sysconfig_poll_status(data, &status);
+ if (ret)
+ return ret;
+
+ if (status & SYSCONFIG_STATUS_DONE)
+ return 0;
+
+ return -EFAULT;
+}
+
+static int sysconfig_isc_disable(struct sysconfig_priv *data)
+{
+ const u8 isc_disable[] = SYSCONFIG_ISC_DISABLE;
+
+ return spi_write(data->spi, isc_disable, sizeof(isc_disable));
+}
+
+static enum fpga_mgr_states ecp5_ops_state(struct fpga_manager *mgr)
+{
+ struct sysconfig_priv *priv = mgr->priv;
+
+ return (gpiod_get_value(priv->done) > 0) ? FPGA_MGR_STATE_OPERATING :
+ FPGA_MGR_STATE_UNKNOWN;
+}
+
+static int ecp5_ops_write_init(struct fpga_manager *mgr,
+ struct fpga_image_info *info,
+ const char *buf, size_t count)
+{
+ struct sysconfig_priv *priv = mgr->priv;
+ struct spi_device *spi = priv->spi;
+ struct device *dev = &mgr->dev;
+ struct gpio_desc *program;
+ struct gpio_desc *init;
+ struct gpio_desc *done;
+ int ret;
+
+ if (info->flags & FPGA_MGR_PARTIAL_RECONFIG) {
+ dev_err(dev, "Partial reconfiguration is not supported\n");
+ return -EOPNOTSUPP;
+ }
+
+ program = priv->program;
+ init = priv->init;
+ done = priv->done;
+
+ /* Enter init mode */
+ gpiod_set_value(program, 1);
+
+ ret = sysconfig_poll_gpio(init, true);
+ if (!ret)
+ ret = sysconfig_poll_gpio(done, false);
+
+ if (ret) {
+ dev_err(dev, "Failed to go to init mode\n");
+ return ret;
+ }
+
+ /* Enter program mode */
+ gpiod_set_value(program, 0);
+
+ ret = sysconfig_poll_gpio(init, false);
+ if (ret) {
+ dev_err(dev, "Failed to go to program mode\n");
+ return ret;
+ }
+
+ /* Enter ISC mode */
+ ret = sysconfig_isc_init(priv);
+ if (ret) {
+ dev_err(dev, "Failed to go to ISC mode\n");
+ return ret;
+ }
+
+ /* Initialize the Address Shift Register */
+ ret = sysconfig_lsc_init_addr(priv);
+ if (ret) {
+ dev_err(dev,
+ "Failed to initialize the Address Shift Register\n");
+ return ret;
+ }
+
+ /*
+ * Lock SPI bus for exclusive usage until FPGA programming is done.
+ * SPI bus will be released in ecp5_ops_write_complete() or on error.
+ */
+ spi_bus_lock(spi->controller);
+
+ /* Prepare for bitstream burst write */
+ ret = sysconfig_lsc_bitstream_burst(priv);
+ if (ret) {
+ dev_err(dev, "Failed to prepare for bitstream burst write\n");
+ spi_bus_unlock(spi->controller);
+ }
+
+ return ret;
+}
+
+static int ecp5_ops_write(struct fpga_manager *mgr, const char *buf, size_t count)
+{
+ struct sysconfig_priv *priv = mgr->priv;
+ struct spi_device *spi = priv->spi;
+ struct spi_transfer xfer = {
+ .tx_buf = buf,
+ .len = count,
+ .cs_change = 1,
+ };
+ struct spi_message msg;
+ int ret;
+
+ spi_message_init_with_transfers(&msg, &xfer, 1);
+ ret = spi_sync_locked(spi, &msg);
+ if (ret)
+ spi_bus_unlock(spi->controller);
+
+ return ret;
+}
+
+static int ecp5_ops_write_complete(struct fpga_manager *mgr,
+ struct fpga_image_info *info)
+{
+ struct sysconfig_priv *priv = mgr->priv;
+ struct spi_device *spi = priv->spi;
+ struct device *dev = &mgr->dev;
+ int ret;
+
+ /* Bitstream burst write is done, release SPI bus */
+ spi_bus_unlock(spi->controller);
+
+ /* Toggle CS and wait for bitstream write to finish */
+ ret = spi_write(spi, NULL, 0);
+ if (!ret)
+ ret = sysconfig_poll_busy(priv);
+
+ if (ret) {
+ dev_err(dev, "Error while waiting bitstream write to finish\n");
+ return ret;
+ }
+
+ /* Exit ISC mode */
+ ret = sysconfig_isc_disable(priv);
+ if (!ret)
+ ret = sysconfig_poll_gpio(priv->done, true);
+
+ if (ret)
+ dev_err(dev, "Failed to finish ISC\n");
+
+ return ret;
+}
+
+static const struct fpga_manager_ops ecp5_fpga_ops = {
+ .state = ecp5_ops_state,
+ .write_init = ecp5_ops_write_init,
+ .write = ecp5_ops_write,
+ .write_complete = ecp5_ops_write_complete,
+};
+
+static int ecp5_probe(struct sysconfig_priv *priv)
+{
+ struct spi_device *spi = priv->spi;
+ struct device *dev = &spi->dev;
+ struct fpga_manager *mgr;
+ int ret;
+
+ if (spi->max_speed_hz > ECP5_SPI_MAX_SPEED_HZ) {
+ dev_err(dev, "SPI speed %u is too high, maximum speed is %u\n",
+ spi->max_speed_hz, ECP5_SPI_MAX_SPEED_HZ);
+ return -EINVAL;
+ }
+
+ priv->isc_erase_operand = ECP5_ISC_ERASE_OPERAND;
+
+ priv->done = devm_gpiod_get(dev, "done", GPIOD_IN);
+ if (IS_ERR(priv->done)) {
+ ret = PTR_ERR(priv->done);
+ dev_err(dev, "Failed to get DONE GPIO: %d\n", ret);
+ return ret;
+ }
+
+ priv->init = devm_gpiod_get(dev, "init", GPIOD_IN);
+ if (IS_ERR(priv->init)) {
+ ret = PTR_ERR(priv->init);
+ dev_err(dev, "Failed to get INIT GPIO: %d\n", ret);
+ return ret;
+ }
+
+ priv->program = devm_gpiod_get(dev, "program", GPIOD_OUT_LOW);
+ if (IS_ERR(priv->program)) {
+ ret = PTR_ERR(priv->program);
+ dev_err(dev, "Failed to get PROGRAM GPIO: %d\n", ret);
+ return ret;
+ }
+
+ mgr = devm_fpga_mgr_register(dev, "Lattice ECP5 SPI FPGA Manager",
+ &ecp5_fpga_ops, priv);
+
+ return PTR_ERR_OR_ZERO(mgr);
+}
+
+static enum fpga_mgr_states machxo2_ops_state(struct fpga_manager *mgr)
+{
+ struct sysconfig_priv *priv = mgr->priv;
+ u32 status;
+ int ret;
+
+ ret = sysconfig_read_status(priv, &status);
+ if (ret || !(status & SYSCONFIG_STATUS_DONE))
+ return FPGA_MGR_STATE_UNKNOWN;
+
+ return FPGA_MGR_STATE_OPERATING;
+}
+
+static int machxo2_ops_write_init(struct fpga_manager *mgr,
+ struct fpga_image_info *info,
+ const char *buf, size_t count)
+{
+ struct sysconfig_priv *priv = mgr->priv;
+ struct device *dev = &mgr->dev;
+ int ret;
+
+ if (info->flags & FPGA_MGR_PARTIAL_RECONFIG) {
+ dev_err(dev, "Partial reconfiguration is not supported\n");
+ return -EOPNOTSUPP;
+ }
+
+ /* Enter ISC mode */
+ ret = sysconfig_isc_init(priv);
+ if (ret) {
+ dev_err(dev, "Failed to go to ISC mode\n");
+ return ret;
+ }
+
+ /* Initialize the Address Shift Register */
+ ret = sysconfig_lsc_init_addr(priv);
+ if (ret)
+ dev_err(dev,
+ "Failed to initialize the Address Shift Register\n");
+
+ return ret;
+}
+
+static int machxo2_ops_write(struct fpga_manager *mgr, const char *buf, size_t count)
+{
+ const u8 lsc_progincr[] = SYSCONFIG_LSC_PROG_INCR_NV;
+ struct sysconfig_priv *priv = mgr->priv;
+ struct device *dev = &mgr->dev;
+ struct spi_transfer xfers[2] = {
+ {
+ .tx_buf = lsc_progincr,
+ .len = sizeof(lsc_progincr),
+ }, {
+ .len = MACHXO2_PAGE_SIZE,
+ },
+ };
+ size_t i;
+ int ret;
+
+ if (count % MACHXO2_PAGE_SIZE) {
+ dev_err(dev, "Malformed payload.\n");
+ return -EINVAL;
+ }
+
+ for (i = 0; i < count; i += MACHXO2_PAGE_SIZE) {
+ xfers[1].tx_buf = buf + i;
+
+ ret = spi_sync_transfer(priv->spi, xfers, 2);
+ if (!ret)
+ ret = sysconfig_poll_busy(priv);
+
+ if (ret) {
+ dev_err(dev, "Failed to write frame %zu of %zu\n",
+ i / MACHXO2_PAGE_SIZE, count / MACHXO2_PAGE_SIZE);
+ return ret;
+ }
+ }
+
+ return 0;
+}
+
+static void machxo2_cleanup(struct sysconfig_priv *data)
+{
+ sysconfig_isc_erase(data);
+ sysconfig_refresh(data);
+}
+
+static int machxo2_ops_write_complete(struct fpga_manager *mgr,
+ struct fpga_image_info *info)
+{
+ int ret, retries = SYSCONFIG_POLL_RETRIES;
+ struct sysconfig_priv *priv = mgr->priv;
+ struct device *dev = &mgr->dev;
+ u32 status;
+
+ ret = sysconfig_isc_prog_done(priv);
+ if (ret) {
+ dev_err(dev, "Failed to enable Self-Download Mode\n");
+ goto fail;
+ }
+
+ ret = sysconfig_isc_disable(priv);
+ if (ret) {
+ dev_err(dev, "Failed to disable Configuration Interface\n");
+ goto fail;
+ }
+
+ while (retries--) {
+ ret = sysconfig_refresh(priv);
+ if (!ret)
+ ret = sysconfig_read_status(priv, &status);
+
+ if (ret) {
+ dev_err(dev, "Failed to refresh\n");
+ break;
+ }
+
+ if (status & SYSCONFIG_STATUS_DONE &&
+ !(status & SYSCONFIG_STATUS_BUSY) &&
+ !(status & SYSCONFIG_STATUS_ERR))
+ return 0;
+ }
+
+fail:
+ machxo2_cleanup(priv);
+
+ return -EFAULT;
+}
+
+static const struct fpga_manager_ops machxo2_fpga_ops = {
+ .state = machxo2_ops_state,
+ .write_init = machxo2_ops_write_init,
+ .write = machxo2_ops_write,
+ .write_complete = machxo2_ops_write_complete,
+};
+
+static int machxo2_probe(struct sysconfig_priv *priv)
+{
+ struct spi_device *spi = priv->spi;
+ struct device *dev = &spi->dev;
+ struct fpga_manager *mgr;
+
+ if (spi->max_speed_hz > MACHXO2_SPI_MAX_SPEED_HZ) {
+ dev_err(dev, "SPI speed %u is too high, maximum speed is %u\n",
+ spi->max_speed_hz, MACHXO2_SPI_MAX_SPEED_HZ);
+ return -EINVAL;
+ }
+
+ priv->isc_enable_operand = MACHXO2_ISC_ENABLE_OPERAND;
+ priv->isc_erase_operand = MACHXO2_ISC_ERASE_OPERAND;
+
+ mgr = devm_fpga_mgr_register(dev, "Lattice MachXO2 SPI FPGA Manager",
+ &machxo2_fpga_ops, priv);
+
+ return PTR_ERR_OR_ZERO(mgr);
+}
+
+typedef int (*lattice_fpga_probe_func)(struct sysconfig_priv *);
+
+static int sysconfig_probe(struct spi_device *spi)
+{
+ const struct spi_device_id *dev_id;
+ lattice_fpga_probe_func probe_func;
+ struct device *dev = &spi->dev;
+ struct sysconfig_priv *priv;
+
+ priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ priv->spi = spi;
+
+ probe_func = of_device_get_match_data(&spi->dev);
+ if (!probe_func) {
+ dev_id = spi_get_device_id(spi);
+ if (!dev_id)
+ return -ENODEV;
+
+ probe_func = (lattice_fpga_probe_func)dev_id->driver_data;
+ }
+
+ if (!probe_func)
+ return -EINVAL;
+
+ return probe_func(priv);
+}
+
+static const struct spi_device_id sysconfig_spi_ids[] = {
+ {
+ .name = "ecp5-fpga-mgr",
+ .driver_data = (kernel_ulong_t)ecp5_probe,
+ }, {
+ .name = "machxo2-fpga-mgr",
+ .driver_data = (kernel_ulong_t)machxo2_probe,
+ }, {},
+};
+MODULE_DEVICE_TABLE(spi, sysconfig_spi_ids);
+
+#if IS_ENABLED(CONFIG_OF)
+static const struct of_device_id sysconfig_of_ids[] = {
+ {
+ .compatible = "lattice,ecp5-fpga-mgr",
+ .data = ecp5_probe,
+ }, {
+ .compatible = "lattice,machxo2-fpga-mgr",
+ .data = machxo2_probe
+ }, {},
+};
+MODULE_DEVICE_TABLE(of, sysconfig_of_ids);
+#endif /* IS_ENABLED(CONFIG_OF) */
+
+static struct spi_driver lattice_sysconfig_driver = {
+ .probe = sysconfig_probe,
+ .id_table = sysconfig_spi_ids,
+ .driver = {
+ .name = "lattice_sysconfig_spi_fpga_mgr",
+ .of_match_table = of_match_ptr(sysconfig_of_ids),
+ },
+};
+
+module_spi_driver(lattice_sysconfig_driver);
+
+MODULE_DESCRIPTION("Lattice sysCONFIG Slave SPI FPGA Manager");
+MODULE_LICENSE("GPL");
--
2.37.2
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