|  | // 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); |