diff options
Diffstat (limited to 'drivers/fpga/lattice-sysconfig.c')
| -rw-r--r-- | drivers/fpga/lattice-sysconfig.c | 397 | 
1 files changed, 397 insertions, 0 deletions
| diff --git a/drivers/fpga/lattice-sysconfig.c b/drivers/fpga/lattice-sysconfig.c new file mode 100644 index 000000000000..ba51a60f672f --- /dev/null +++ b/drivers/fpga/lattice-sysconfig.c @@ -0,0 +1,397 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Lattice FPGA sysCONFIG interface functions independent of port type. + */ + +#include <linux/delay.h> +#include <linux/fpga/fpga-mgr.h> +#include <linux/gpio/consumer.h> +#include <linux/iopoll.h> + +#include "lattice-sysconfig.h" + +static int sysconfig_cmd_write(struct sysconfig_priv *priv, const void *buf, +			       size_t buf_len) +{ +	return priv->command_transfer(priv, buf, buf_len, NULL, 0); +} + +static int sysconfig_cmd_read(struct sysconfig_priv *priv, const void *tx_buf, +			      size_t tx_len, void *rx_buf, size_t rx_len) +{ +	return priv->command_transfer(priv, tx_buf, tx_len, rx_buf, rx_len); +} + +static int sysconfig_read_busy(struct sysconfig_priv *priv) +{ +	const u8 lsc_check_busy[] = SYSCONFIG_LSC_CHECK_BUSY; +	u8 busy; +	int ret; + +	ret = sysconfig_cmd_read(priv, lsc_check_busy, sizeof(lsc_check_busy), +				 &busy, sizeof(busy)); + +	return ret ? : busy; +} + +static int sysconfig_poll_busy(struct sysconfig_priv *priv) +{ +	int ret, busy; + +	ret = read_poll_timeout(sysconfig_read_busy, busy, busy <= 0, +				SYSCONFIG_POLL_INTERVAL_US, +				SYSCONFIG_POLL_BUSY_TIMEOUT_US, false, priv); + +	return ret ? : busy; +} + +static int sysconfig_read_status(struct sysconfig_priv *priv, u32 *status) +{ +	const u8 lsc_read_status[] = SYSCONFIG_LSC_READ_STATUS; +	__be32 device_status; +	int ret; + +	ret = sysconfig_cmd_read(priv, 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 *priv, u32 *status) +{ +	int ret = sysconfig_poll_busy(priv); + +	if (ret) +		return ret; + +	return sysconfig_read_status(priv, status); +} + +static int sysconfig_poll_gpio(struct gpio_desc *gpio, bool is_active) +{ +	int ret, val; + +	ret = read_poll_timeout(gpiod_get_value, val, +				val < 0 || !!val == is_active, +				SYSCONFIG_POLL_INTERVAL_US, +				SYSCONFIG_POLL_GPIO_TIMEOUT_US, false, gpio); + +	if (val < 0) +		return val; + +	return ret; +} + +static int sysconfig_gpio_refresh(struct sysconfig_priv *priv) +{ +	struct gpio_desc *program = priv->program; +	struct gpio_desc *init = priv->init; +	struct gpio_desc *done = priv->done; +	int ret; + +	/* Enter init mode */ +	gpiod_set_value(program, 1); + +	ret = sysconfig_poll_gpio(init, true); +	if (!ret) +		ret = sysconfig_poll_gpio(done, false); + +	if (ret) +		return ret; + +	/* Enter program mode */ +	gpiod_set_value(program, 0); + +	return sysconfig_poll_gpio(init, false); +} + +static int sysconfig_lsc_refresh(struct sysconfig_priv *priv) +{ +	static const u8 lsc_refresh[] = SYSCONFIG_LSC_REFRESH; +	int ret; + +	ret = sysconfig_cmd_write(priv, lsc_refresh, sizeof(lsc_refresh)); +	if (ret) +		return ret; + +	usleep_range(4000, 8000); + +	return 0; +} + +static int sysconfig_refresh(struct sysconfig_priv *priv) +{ +	struct gpio_desc *program = priv->program; +	struct gpio_desc *init = priv->init; +	struct gpio_desc *done = priv->done; + +	if (program && init && done) +		return sysconfig_gpio_refresh(priv); + +	return sysconfig_lsc_refresh(priv); +} + +static int sysconfig_isc_enable(struct sysconfig_priv *priv) +{ +	u8 isc_enable[] = SYSCONFIG_ISC_ENABLE; +	u32 status; +	int ret; + +	ret = sysconfig_cmd_write(priv, isc_enable, sizeof(isc_enable)); +	if (ret) +		return ret; + +	ret = sysconfig_poll_status(priv, &status); +	if (ret) +		return ret; + +	if (status & SYSCONFIG_STATUS_FAIL) +		return -EFAULT; + +	return 0; +} + +static int sysconfig_isc_erase(struct sysconfig_priv *priv) +{ +	u8 isc_erase[] = SYSCONFIG_ISC_ERASE; +	u32 status; +	int ret; + +	ret = sysconfig_cmd_write(priv, isc_erase, sizeof(isc_erase)); +	if (ret) +		return ret; + +	ret = sysconfig_poll_status(priv, &status); +	if (ret) +		return ret; + +	if (status & SYSCONFIG_STATUS_FAIL) +		return -EFAULT; + +	return 0; +} + +static int sysconfig_isc_init(struct sysconfig_priv *priv) +{ +	int ret = sysconfig_isc_enable(priv); + +	if (ret) +		return ret; + +	return sysconfig_isc_erase(priv); +} + +static int sysconfig_lsc_init_addr(struct sysconfig_priv *priv) +{ +	const u8 lsc_init_addr[] = SYSCONFIG_LSC_INIT_ADDR; + +	return sysconfig_cmd_write(priv, lsc_init_addr, sizeof(lsc_init_addr)); +} + +static int sysconfig_burst_write_init(struct sysconfig_priv *priv) +{ +	return priv->bitstream_burst_write_init(priv); +} + +static int sysconfig_burst_write_complete(struct sysconfig_priv *priv) +{ +	return priv->bitstream_burst_write_complete(priv); +} + +static int sysconfig_bitstream_burst_write(struct sysconfig_priv *priv, +					   const char *buf, size_t count) +{ +	int ret = priv->bitstream_burst_write(priv, buf, count); + +	if (ret) +		sysconfig_burst_write_complete(priv); + +	return ret; +} + +static int sysconfig_isc_disable(struct sysconfig_priv *priv) +{ +	const u8 isc_disable[] = SYSCONFIG_ISC_DISABLE; + +	return sysconfig_cmd_write(priv, isc_disable, sizeof(isc_disable)); +} + +static void sysconfig_cleanup(struct sysconfig_priv *priv) +{ +	sysconfig_isc_erase(priv); +	sysconfig_refresh(priv); +} + +static int sysconfig_isc_finish(struct sysconfig_priv *priv) +{ +	struct gpio_desc *done_gpio = priv->done; +	u32 status; +	int ret; + +	if (done_gpio) { +		ret = sysconfig_isc_disable(priv); +		if (ret) +			return ret; + +		return sysconfig_poll_gpio(done_gpio, true); +	} + +	ret = sysconfig_poll_status(priv, &status); +	if (ret) +		return ret; + +	if ((status & SYSCONFIG_STATUS_DONE) && +	    !(status & SYSCONFIG_STATUS_BUSY) && +	    !(status & SYSCONFIG_STATUS_ERR)) +		return sysconfig_isc_disable(priv); + +	return -EFAULT; +} + +static enum fpga_mgr_states sysconfig_ops_state(struct fpga_manager *mgr) +{ +	struct sysconfig_priv *priv = mgr->priv; +	struct gpio_desc *done = priv->done; +	u32 status; +	int ret; + +	if (done && (gpiod_get_value(done) > 0)) +		return FPGA_MGR_STATE_OPERATING; + +	ret = sysconfig_read_status(priv, &status); +	if (!ret && (status & SYSCONFIG_STATUS_DONE)) +		return FPGA_MGR_STATE_OPERATING; + +	return FPGA_MGR_STATE_UNKNOWN; +} + +static int sysconfig_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 program mode */ +	ret = sysconfig_refresh(priv); +	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; +	} + +	/* Prepare for bitstream burst write */ +	ret = sysconfig_burst_write_init(priv); +	if (ret) +		dev_err(dev, "Failed to prepare for bitstream burst write\n"); + +	return ret; +} + +static int sysconfig_ops_write(struct fpga_manager *mgr, const char *buf, +			       size_t count) +{ +	return sysconfig_bitstream_burst_write(mgr->priv, buf, count); +} + +static int sysconfig_ops_write_complete(struct fpga_manager *mgr, +					struct fpga_image_info *info) +{ +	struct sysconfig_priv *priv = mgr->priv; +	struct device *dev = &mgr->dev; +	int ret; + +	ret = sysconfig_burst_write_complete(priv); +	if (!ret) +		ret = sysconfig_poll_busy(priv); + +	if (ret) { +		dev_err(dev, "Error while waiting bitstream write to finish\n"); +		goto fail; +	} + +	ret = sysconfig_isc_finish(priv); + +fail: +	if (ret) +		sysconfig_cleanup(priv); + +	return ret; +} + +static const struct fpga_manager_ops sysconfig_fpga_mgr_ops = { +	.state = sysconfig_ops_state, +	.write_init = sysconfig_ops_write_init, +	.write = sysconfig_ops_write, +	.write_complete = sysconfig_ops_write_complete, +}; + +int sysconfig_probe(struct sysconfig_priv *priv) +{ +	struct gpio_desc *program, *init, *done; +	struct device *dev = priv->dev; +	struct fpga_manager *mgr; + +	if (!dev) +		return -ENODEV; + +	if (!priv->command_transfer || +	    !priv->bitstream_burst_write_init || +	    !priv->bitstream_burst_write || +	    !priv->bitstream_burst_write_complete) { +		dev_err(dev, "Essential callback is missing\n"); +		return -EINVAL; +	} + +	program = devm_gpiod_get_optional(dev, "program", GPIOD_OUT_LOW); +	if (IS_ERR(program)) +		return dev_err_probe(dev, PTR_ERR(program), +				     "Failed to get PROGRAM GPIO\n"); + +	init = devm_gpiod_get_optional(dev, "init", GPIOD_IN); +	if (IS_ERR(init)) +		return dev_err_probe(dev, PTR_ERR(init), +				     "Failed to get INIT GPIO\n"); + +	done = devm_gpiod_get_optional(dev, "done", GPIOD_IN); +	if (IS_ERR(done)) +		return dev_err_probe(dev, PTR_ERR(done), +				     "Failed to get DONE GPIO\n"); + +	priv->program = program; +	priv->init = init; +	priv->done = done; + +	mgr = devm_fpga_mgr_register(dev, "Lattice sysCONFIG FPGA Manager", +				     &sysconfig_fpga_mgr_ops, priv); + +	return PTR_ERR_OR_ZERO(mgr); +} +EXPORT_SYMBOL(sysconfig_probe); + +MODULE_DESCRIPTION("Lattice sysCONFIG FPGA Manager Core"); +MODULE_LICENSE("GPL"); | 
