drivers/bus/fsl-mc/mc-sys.c - linux - Git at Google

 // SPDX-License-Identifier: (GPL-2.0+ OR BSD-3-Clause)
 /*
  * Copyright 2013-2016 Freescale Semiconductor Inc.
  *
  * I/O services to send MC commands to the MC hardware
  *
  */

 #include <linux/delay.h>
 #include <linux/slab.h>
 #include <linux/ioport.h>
 #include <linux/device.h>
 #include <linux/io.h>
 #include <linux/io-64-nonatomic-hi-lo.h>
 #include <linux/fsl/mc.h>

 #include "fsl-mc-private.h"

 /**
  * Timeout in milliseconds to wait for the completion of an MC command
  */
 #define MC_CMD_COMPLETION_TIMEOUT_MS	500

 /*
  * usleep_range() min and max values used to throttle down polling
  * iterations while waiting for MC command completion
  */
 #define MC_CMD_COMPLETION_POLLING_MIN_SLEEP_USECS    10
 #define MC_CMD_COMPLETION_POLLING_MAX_SLEEP_USECS    500

 static enum mc_cmd_status mc_cmd_hdr_read_status(struct fsl_mc_command *cmd)
 {
 	struct mc_cmd_header *hdr = (struct mc_cmd_header *)&cmd->header;

 	return (enum mc_cmd_status)hdr->status;
 }

 static u16 mc_cmd_hdr_read_cmdid(struct fsl_mc_command *cmd)
 {
 	struct mc_cmd_header *hdr = (struct mc_cmd_header *)&cmd->header;
 	u16 cmd_id = le16_to_cpu(hdr->cmd_id);

 	return cmd_id;
 }

 static int mc_status_to_error(enum mc_cmd_status status)
 {
 	static const int mc_status_to_error_map[] = {
 		[MC_CMD_STATUS_OK] = 0,
 		[MC_CMD_STATUS_AUTH_ERR] = -EACCES,
 		[MC_CMD_STATUS_NO_PRIVILEGE] = -EPERM,
 		[MC_CMD_STATUS_DMA_ERR] = -EIO,
 		[MC_CMD_STATUS_CONFIG_ERR] = -ENXIO,
 		[MC_CMD_STATUS_TIMEOUT] = -ETIMEDOUT,
 		[MC_CMD_STATUS_NO_RESOURCE] = -ENAVAIL,
 		[MC_CMD_STATUS_NO_MEMORY] = -ENOMEM,
 		[MC_CMD_STATUS_BUSY] = -EBUSY,
 		[MC_CMD_STATUS_UNSUPPORTED_OP] = -ENOTSUPP,
 		[MC_CMD_STATUS_INVALID_STATE] = -ENODEV,
 	};

 	if ((u32)status >= ARRAY_SIZE(mc_status_to_error_map))
 		return -EINVAL;

 	return mc_status_to_error_map[status];
 }

 static const char *mc_status_to_string(enum mc_cmd_status status)
 {
 	static const char *const status_strings[] = {
 		[MC_CMD_STATUS_OK] = "Command completed successfully",
 		[MC_CMD_STATUS_READY] = "Command ready to be processed",
 		[MC_CMD_STATUS_AUTH_ERR] = "Authentication error",
 		[MC_CMD_STATUS_NO_PRIVILEGE] = "No privilege",
 		[MC_CMD_STATUS_DMA_ERR] = "DMA or I/O error",
 		[MC_CMD_STATUS_CONFIG_ERR] = "Configuration error",
 		[MC_CMD_STATUS_TIMEOUT] = "Operation timed out",
 		[MC_CMD_STATUS_NO_RESOURCE] = "No resources",
 		[MC_CMD_STATUS_NO_MEMORY] = "No memory available",
 		[MC_CMD_STATUS_BUSY] = "Device is busy",
 		[MC_CMD_STATUS_UNSUPPORTED_OP] = "Unsupported operation",
 		[MC_CMD_STATUS_INVALID_STATE] = "Invalid state"
 	};

 	if ((unsigned int)status >= ARRAY_SIZE(status_strings))
 		return "Unknown MC error";

 	return status_strings[status];
 }

 /**
  * mc_write_command - writes a command to a Management Complex (MC) portal
  *
  * @portal: pointer to an MC portal
  * @cmd: pointer to a filled command
  */
 static inline void mc_write_command(struct fsl_mc_command __iomem *portal,
 				    struct fsl_mc_command *cmd)
 {
 	int i;

 	/* copy command parameters into the portal */
 	for (i = 0; i < MC_CMD_NUM_OF_PARAMS; i++)
 		/*
 		 * Data is already in the expected LE byte-order. Do an
 		 * extra LE -> CPU conversion so that the CPU -> LE done in
 		 * the device io write api puts it back in the right order.
 		 */
 		writeq_relaxed(le64_to_cpu(cmd->params[i]), &portal->params[i]);

 	/* submit the command by writing the header */
 	writeq(le64_to_cpu(cmd->header), &portal->header);
 }

 /**
  * mc_read_response - reads the response for the last MC command from a
  * Management Complex (MC) portal
  *
  * @portal: pointer to an MC portal
  * @resp: pointer to command response buffer
  *
  * Returns MC_CMD_STATUS_OK on Success; Error code otherwise.
  */
 static inline enum mc_cmd_status mc_read_response(struct fsl_mc_command __iomem
 						  *portal,
 						  struct fsl_mc_command *resp)
 {
 	int i;
 	enum mc_cmd_status status;

 	/* Copy command response header from MC portal: */
 	resp->header = cpu_to_le64(readq_relaxed(&portal->header));
 	status = mc_cmd_hdr_read_status(resp);
 	if (status != MC_CMD_STATUS_OK)
 		return status;

 	/* Copy command response data from MC portal: */
 	for (i = 0; i < MC_CMD_NUM_OF_PARAMS; i++)
 		/*
 		 * Data is expected to be in LE byte-order. Do an
 		 * extra CPU -> LE to revert the LE -> CPU done in
 		 * the device io read api.
 		 */
 		resp->params[i] =
 			cpu_to_le64(readq_relaxed(&portal->params[i]));

 	return status;
 }

 /**
  * Waits for the completion of an MC command doing preemptible polling.
  * uslepp_range() is called between polling iterations.
  *
  * @mc_io: MC I/O object to be used
  * @cmd: command buffer to receive MC response
  * @mc_status: MC command completion status
  */
 static int mc_polling_wait_preemptible(struct fsl_mc_io *mc_io,
 				       struct fsl_mc_command *cmd,
 				       enum mc_cmd_status *mc_status)
 {
 	enum mc_cmd_status status;
 	unsigned long jiffies_until_timeout =
 		jiffies + msecs_to_jiffies(MC_CMD_COMPLETION_TIMEOUT_MS);

 	/*
 	 * Wait for response from the MC hardware:
 	 */
 	for (;;) {
 		status = mc_read_response(mc_io->portal_virt_addr, cmd);
 		if (status != MC_CMD_STATUS_READY)
 			break;

 		/*
 		 * TODO: When MC command completion interrupts are supported
 		 * call wait function here instead of usleep_range()
 		 */
 		usleep_range(MC_CMD_COMPLETION_POLLING_MIN_SLEEP_USECS,
 			     MC_CMD_COMPLETION_POLLING_MAX_SLEEP_USECS);

 		if (time_after_eq(jiffies, jiffies_until_timeout)) {
 			dev_dbg(mc_io->dev,
 				"MC command timed out (portal: %pa, dprc handle: %#x, command: %#x)\n",
 				 &mc_io->portal_phys_addr,
 				 (unsigned int)mc_cmd_hdr_read_token(cmd),
 				 (unsigned int)mc_cmd_hdr_read_cmdid(cmd));

 			return -ETIMEDOUT;
 		}
 	}

 	*mc_status = status;
 	return 0;
 }

 /**
  * Waits for the completion of an MC command doing atomic polling.
  * udelay() is called between polling iterations.
  *
  * @mc_io: MC I/O object to be used
  * @cmd: command buffer to receive MC response
  * @mc_status: MC command completion status
  */
 static int mc_polling_wait_atomic(struct fsl_mc_io *mc_io,
 				  struct fsl_mc_command *cmd,
 				  enum mc_cmd_status *mc_status)
 {
 	enum mc_cmd_status status;
 	unsigned long timeout_usecs = MC_CMD_COMPLETION_TIMEOUT_MS * 1000;

 	BUILD_BUG_ON((MC_CMD_COMPLETION_TIMEOUT_MS * 1000) %
 		     MC_CMD_COMPLETION_POLLING_MAX_SLEEP_USECS != 0);

 	for (;;) {
 		status = mc_read_response(mc_io->portal_virt_addr, cmd);
 		if (status != MC_CMD_STATUS_READY)
 			break;

 		udelay(MC_CMD_COMPLETION_POLLING_MAX_SLEEP_USECS);
 		timeout_usecs -= MC_CMD_COMPLETION_POLLING_MAX_SLEEP_USECS;
 		if (timeout_usecs == 0) {
 			dev_dbg(mc_io->dev,
 				"MC command timed out (portal: %pa, dprc handle: %#x, command: %#x)\n",
 				 &mc_io->portal_phys_addr,
 				 (unsigned int)mc_cmd_hdr_read_token(cmd),
 				 (unsigned int)mc_cmd_hdr_read_cmdid(cmd));

 			return -ETIMEDOUT;
 		}
 	}

 	*mc_status = status;
 	return 0;
 }

 /**
  * Sends a command to the MC device using the given MC I/O object
  *
  * @mc_io: MC I/O object to be used
  * @cmd: command to be sent
  *
  * Returns '0' on Success; Error code otherwise.
  */
 int mc_send_command(struct fsl_mc_io *mc_io, struct fsl_mc_command *cmd)
 {
 	int error;
 	enum mc_cmd_status status;
 	unsigned long irq_flags = 0;

 	if (in_irq() && !(mc_io->flags & FSL_MC_IO_ATOMIC_CONTEXT_PORTAL))
 		return -EINVAL;

 	if (mc_io->flags & FSL_MC_IO_ATOMIC_CONTEXT_PORTAL)
 		spin_lock_irqsave(&mc_io->spinlock, irq_flags);
 	else
 		mutex_lock(&mc_io->mutex);

 	/*
 	 * Send command to the MC hardware:
 	 */
 	mc_write_command(mc_io->portal_virt_addr, cmd);

 	/*
 	 * Wait for response from the MC hardware:
 	 */
 	if (!(mc_io->flags & FSL_MC_IO_ATOMIC_CONTEXT_PORTAL))
 		error = mc_polling_wait_preemptible(mc_io, cmd, &status);
 	else
 		error = mc_polling_wait_atomic(mc_io, cmd, &status);

 	if (error < 0)
 		goto common_exit;

 	if (status != MC_CMD_STATUS_OK) {
 		dev_dbg(mc_io->dev,
 			"MC command failed: portal: %pa, dprc handle: %#x, command: %#x, status: %s (%#x)\n",
 			 &mc_io->portal_phys_addr,
 			 (unsigned int)mc_cmd_hdr_read_token(cmd),
 			 (unsigned int)mc_cmd_hdr_read_cmdid(cmd),
 			 mc_status_to_string(status),
 			 (unsigned int)status);

 		error = mc_status_to_error(status);
 		goto common_exit;
 	}

 	error = 0;
 common_exit:
 	if (mc_io->flags & FSL_MC_IO_ATOMIC_CONTEXT_PORTAL)
 		spin_unlock_irqrestore(&mc_io->spinlock, irq_flags);
 	else
 		mutex_unlock(&mc_io->mutex);

 	return error;
 }
 EXPORT_SYMBOL_GPL(mc_send_command);
	// SPDX-License-Identifier: (GPL-2.0+ OR BSD-3-Clause)
	/*
	* Copyright 2013-2016 Freescale Semiconductor Inc.
	*
	* I/O services to send MC commands to the MC hardware
	*
	*/

	#include <linux/delay.h>
	#include <linux/slab.h>
	#include <linux/ioport.h>
	#include <linux/device.h>
	#include <linux/io.h>
	#include <linux/io-64-nonatomic-hi-lo.h>
	#include <linux/fsl/mc.h>

	#include "fsl-mc-private.h"

	/**
	* Timeout in milliseconds to wait for the completion of an MC command
	*/
	#define MC_CMD_COMPLETION_TIMEOUT_MS 500

	/*
	* usleep_range() min and max values used to throttle down polling
	* iterations while waiting for MC command completion
	*/
	#define MC_CMD_COMPLETION_POLLING_MIN_SLEEP_USECS 10
	#define MC_CMD_COMPLETION_POLLING_MAX_SLEEP_USECS 500

	static enum mc_cmd_status mc_cmd_hdr_read_status(struct fsl_mc_command *cmd)
	{
	struct mc_cmd_header hdr = (struct mc_cmd_header )&cmd->header;

	return (enum mc_cmd_status)hdr->status;
	}

	static u16 mc_cmd_hdr_read_cmdid(struct fsl_mc_command *cmd)
	{
	struct mc_cmd_header hdr = (struct mc_cmd_header )&cmd->header;
	u16 cmd_id = le16_to_cpu(hdr->cmd_id);

	return cmd_id;
	}

	static int mc_status_to_error(enum mc_cmd_status status)
	{
	static const int mc_status_to_error_map[] = {
	[MC_CMD_STATUS_OK] = 0,
	[MC_CMD_STATUS_AUTH_ERR] = -EACCES,
	[MC_CMD_STATUS_NO_PRIVILEGE] = -EPERM,
	[MC_CMD_STATUS_DMA_ERR] = -EIO,
	[MC_CMD_STATUS_CONFIG_ERR] = -ENXIO,
	[MC_CMD_STATUS_TIMEOUT] = -ETIMEDOUT,
	[MC_CMD_STATUS_NO_RESOURCE] = -ENAVAIL,
	[MC_CMD_STATUS_NO_MEMORY] = -ENOMEM,
	[MC_CMD_STATUS_BUSY] = -EBUSY,
	[MC_CMD_STATUS_UNSUPPORTED_OP] = -ENOTSUPP,
	[MC_CMD_STATUS_INVALID_STATE] = -ENODEV,
	};

	if ((u32)status >= ARRAY_SIZE(mc_status_to_error_map))
	return -EINVAL;

	return mc_status_to_error_map[status];
	}

	static const char *mc_status_to_string(enum mc_cmd_status status)
	{
	static const char *const status_strings[] = {
	[MC_CMD_STATUS_OK] = "Command completed successfully",
	[MC_CMD_STATUS_READY] = "Command ready to be processed",
	[MC_CMD_STATUS_AUTH_ERR] = "Authentication error",
	[MC_CMD_STATUS_NO_PRIVILEGE] = "No privilege",
	[MC_CMD_STATUS_DMA_ERR] = "DMA or I/O error",
	[MC_CMD_STATUS_CONFIG_ERR] = "Configuration error",
	[MC_CMD_STATUS_TIMEOUT] = "Operation timed out",
	[MC_CMD_STATUS_NO_RESOURCE] = "No resources",
	[MC_CMD_STATUS_NO_MEMORY] = "No memory available",
	[MC_CMD_STATUS_BUSY] = "Device is busy",
	[MC_CMD_STATUS_UNSUPPORTED_OP] = "Unsupported operation",
	[MC_CMD_STATUS_INVALID_STATE] = "Invalid state"
	};

	if ((unsigned int)status >= ARRAY_SIZE(status_strings))
	return "Unknown MC error";

	return status_strings[status];
	}

	/**
	* mc_write_command - writes a command to a Management Complex (MC) portal
	*
	* @portal: pointer to an MC portal
	* @cmd: pointer to a filled command
	*/
	static inline void mc_write_command(struct fsl_mc_command __iomem *portal,
	struct fsl_mc_command *cmd)
	{
	int i;

	/* copy command parameters into the portal */
	for (i = 0; i < MC_CMD_NUM_OF_PARAMS; i++)
	/*
	* Data is already in the expected LE byte-order. Do an
	* extra LE -> CPU conversion so that the CPU -> LE done in
	* the device io write api puts it back in the right order.
	*/
	writeq_relaxed(le64_to_cpu(cmd->params[i]), &portal->params[i]);

	/* submit the command by writing the header */
	writeq(le64_to_cpu(cmd->header), &portal->header);
	}

	/**
	* mc_read_response - reads the response for the last MC command from a
	* Management Complex (MC) portal
	*
	* @portal: pointer to an MC portal
	* @resp: pointer to command response buffer
	*
	* Returns MC_CMD_STATUS_OK on Success; Error code otherwise.
	*/
	static inline enum mc_cmd_status mc_read_response(struct fsl_mc_command __iomem
	*portal,
	struct fsl_mc_command *resp)
	{
	int i;
	enum mc_cmd_status status;

	/* Copy command response header from MC portal: */
	resp->header = cpu_to_le64(readq_relaxed(&portal->header));
	status = mc_cmd_hdr_read_status(resp);
	if (status != MC_CMD_STATUS_OK)
	return status;

	/* Copy command response data from MC portal: */
	for (i = 0; i < MC_CMD_NUM_OF_PARAMS; i++)
	/*
	* Data is expected to be in LE byte-order. Do an
	* extra CPU -> LE to revert the LE -> CPU done in
	* the device io read api.
	*/
	resp->params[i] =
	cpu_to_le64(readq_relaxed(&portal->params[i]));

	return status;
	}

	/**
	* Waits for the completion of an MC command doing preemptible polling.
	* uslepp_range() is called between polling iterations.
	*
	* @mc_io: MC I/O object to be used
	* @cmd: command buffer to receive MC response
	* @mc_status: MC command completion status
	*/
	static int mc_polling_wait_preemptible(struct fsl_mc_io *mc_io,
	struct fsl_mc_command *cmd,
	enum mc_cmd_status *mc_status)
	{
	enum mc_cmd_status status;
	unsigned long jiffies_until_timeout =
	jiffies + msecs_to_jiffies(MC_CMD_COMPLETION_TIMEOUT_MS);

	/*
	* Wait for response from the MC hardware:
	*/
	for (;;) {
	status = mc_read_response(mc_io->portal_virt_addr, cmd);
	if (status != MC_CMD_STATUS_READY)
	break;

	/*
	* TODO: When MC command completion interrupts are supported
	* call wait function here instead of usleep_range()
	*/
	usleep_range(MC_CMD_COMPLETION_POLLING_MIN_SLEEP_USECS,
	MC_CMD_COMPLETION_POLLING_MAX_SLEEP_USECS);

	if (time_after_eq(jiffies, jiffies_until_timeout)) {
	dev_dbg(mc_io->dev,
	"MC command timed out (portal: %pa, dprc handle: %#x, command: %#x)\n",
	&mc_io->portal_phys_addr,
	(unsigned int)mc_cmd_hdr_read_token(cmd),
	(unsigned int)mc_cmd_hdr_read_cmdid(cmd));

	return -ETIMEDOUT;
	}
	}

	*mc_status = status;
	return 0;
	}

	/**
	* Waits for the completion of an MC command doing atomic polling.
	* udelay() is called between polling iterations.
	*
	* @mc_io: MC I/O object to be used
	* @cmd: command buffer to receive MC response
	* @mc_status: MC command completion status
	*/
	static int mc_polling_wait_atomic(struct fsl_mc_io *mc_io,
	struct fsl_mc_command *cmd,
	enum mc_cmd_status *mc_status)
	{
	enum mc_cmd_status status;
	unsigned long timeout_usecs = MC_CMD_COMPLETION_TIMEOUT_MS * 1000;

	BUILD_BUG_ON((MC_CMD_COMPLETION_TIMEOUT_MS * 1000) %
	MC_CMD_COMPLETION_POLLING_MAX_SLEEP_USECS != 0);

	for (;;) {
	status = mc_read_response(mc_io->portal_virt_addr, cmd);
	if (status != MC_CMD_STATUS_READY)
	break;

	udelay(MC_CMD_COMPLETION_POLLING_MAX_SLEEP_USECS);
	timeout_usecs -= MC_CMD_COMPLETION_POLLING_MAX_SLEEP_USECS;
	if (timeout_usecs == 0) {
	dev_dbg(mc_io->dev,
	"MC command timed out (portal: %pa, dprc handle: %#x, command: %#x)\n",
	&mc_io->portal_phys_addr,
	(unsigned int)mc_cmd_hdr_read_token(cmd),
	(unsigned int)mc_cmd_hdr_read_cmdid(cmd));

	return -ETIMEDOUT;
	}
	}

	*mc_status = status;
	return 0;
	}

	/**
	* Sends a command to the MC device using the given MC I/O object
	*
	* @mc_io: MC I/O object to be used
	* @cmd: command to be sent
	*
	* Returns '0' on Success; Error code otherwise.
	*/
	int mc_send_command(struct fsl_mc_io mc_io, struct fsl_mc_command cmd)
	{
	int error;
	enum mc_cmd_status status;
	unsigned long irq_flags = 0;

	if (in_irq() && !(mc_io->flags & FSL_MC_IO_ATOMIC_CONTEXT_PORTAL))
	return -EINVAL;

	if (mc_io->flags & FSL_MC_IO_ATOMIC_CONTEXT_PORTAL)
	spin_lock_irqsave(&mc_io->spinlock, irq_flags);
	else
	mutex_lock(&mc_io->mutex);

	/*
	* Send command to the MC hardware:
	*/
	mc_write_command(mc_io->portal_virt_addr, cmd);

	/*
	* Wait for response from the MC hardware:
	*/
	if (!(mc_io->flags & FSL_MC_IO_ATOMIC_CONTEXT_PORTAL))
	error = mc_polling_wait_preemptible(mc_io, cmd, &status);
	else
	error = mc_polling_wait_atomic(mc_io, cmd, &status);

	if (error < 0)
	goto common_exit;

	if (status != MC_CMD_STATUS_OK) {
	dev_dbg(mc_io->dev,
	"MC command failed: portal: %pa, dprc handle: %#x, command: %#x, status: %s (%#x)\n",
	&mc_io->portal_phys_addr,
	(unsigned int)mc_cmd_hdr_read_token(cmd),
	(unsigned int)mc_cmd_hdr_read_cmdid(cmd),
	mc_status_to_string(status),
	(unsigned int)status);

	error = mc_status_to_error(status);
	goto common_exit;
	}

	error = 0;
	common_exit:
	if (mc_io->flags & FSL_MC_IO_ATOMIC_CONTEXT_PORTAL)
	spin_unlock_irqrestore(&mc_io->spinlock, irq_flags);
	else
	mutex_unlock(&mc_io->mutex);

	return error;
	}
	EXPORT_SYMBOL_GPL(mc_send_command);