// 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;
}
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;
}
/**
* mc_polling_wait_preemptible() - 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;
}
/**
* mc_polling_wait_atomic() - 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;
}
/**
* mc_send_command() - 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)
raw_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)
raw_spin_unlock_irqrestore(&mc_io->spinlock, irq_flags);
else
mutex_unlock(&mc_io->mutex);
return error;
}
EXPORT_SYMBOL_GPL(mc_send_command);
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