// SPDX-License-Identifier: GPL-2.0
/*
* Thunderbolt DMA configuration based mailbox support
*
* Copyright (C) 2017, Intel Corporation
* Authors: Michael Jamet <michael.jamet@intel.com>
* Mika Westerberg <mika.westerberg@linux.intel.com>
*/
#include <linux/delay.h>
#include <linux/slab.h>
#include "dma_port.h"
#include "tb_regs.h"
#define DMA_PORT_CAP 0x3e
#define MAIL_DATA 1
#define MAIL_DATA_DWORDS 16
#define MAIL_IN 17
#define MAIL_IN_CMD_SHIFT 28
#define MAIL_IN_CMD_MASK GENMASK(31, 28)
#define MAIL_IN_CMD_FLASH_WRITE 0x0
#define MAIL_IN_CMD_FLASH_UPDATE_AUTH 0x1
#define MAIL_IN_CMD_FLASH_READ 0x2
#define MAIL_IN_CMD_POWER_CYCLE 0x4
#define MAIL_IN_DWORDS_SHIFT 24
#define MAIL_IN_DWORDS_MASK GENMASK(27, 24)
#define MAIL_IN_ADDRESS_SHIFT 2
#define MAIL_IN_ADDRESS_MASK GENMASK(23, 2)
#define MAIL_IN_CSS BIT(1)
#define MAIL_IN_OP_REQUEST BIT(0)
#define MAIL_OUT 18
#define MAIL_OUT_STATUS_RESPONSE BIT(29)
#define MAIL_OUT_STATUS_CMD_SHIFT 4
#define MAIL_OUT_STATUS_CMD_MASK GENMASK(7, 4)
#define MAIL_OUT_STATUS_MASK GENMASK(3, 0)
#define MAIL_OUT_STATUS_COMPLETED 0
#define MAIL_OUT_STATUS_ERR_AUTH 1
#define MAIL_OUT_STATUS_ERR_ACCESS 2
#define DMA_PORT_TIMEOUT 5000 /* ms */
#define DMA_PORT_RETRIES 3
/**
* struct tb_dma_port - DMA control port
* @sw: Switch the DMA port belongs to
* @port: Switch port number where DMA capability is found
* @base: Start offset of the mailbox registers
* @buf: Temporary buffer to store a single block
*/
struct tb_dma_port {
struct tb_switch *sw;
u8 port;
u32 base;
u8 *buf;
};
/*
* When the switch is in safe mode it supports very little functionality
* so we don't validate that much here.
*/
static bool dma_port_match(const struct tb_cfg_request *req,
const struct ctl_pkg *pkg)
{
u64 route = tb_cfg_get_route(pkg->buffer) & ~BIT_ULL(63);
if (pkg->frame.eof == TB_CFG_PKG_ERROR)
return true;
if (pkg->frame.eof != req->response_type)
return false;
if (route != tb_cfg_get_route(req->request))
return false;
if (pkg->frame.size != req->response_size)
return false;
return true;
}
static bool dma_port_copy(struct tb_cfg_request *req, const struct ctl_pkg *pkg)
{
memcpy(req->response, pkg->buffer, req->response_size);
return true;
}
static int dma_port_read(struct tb_ctl *ctl, void *buffer, u64 route,
u32 port, u32 offset, u32 length, int timeout_msec)
{
struct cfg_read_pkg request = {
.header = tb_cfg_make_header(route),
.addr = {
.seq = 1,
.port = port,
.space = TB_CFG_PORT,
.offset = offset,
.length = length,
},
};
struct tb_cfg_request *req;
struct cfg_write_pkg reply;
struct tb_cfg_result res;
req = tb_cfg_request_alloc();
if (!req)
return -ENOMEM;
req->match = dma_port_match;
req->copy = dma_port_copy;
req->request = &request;
req->request_size = sizeof(request);
req->request_type = TB_CFG_PKG_READ;
req->response = &reply;
req->response_size = 12 + 4 * length;
req->response_type = TB_CFG_PKG_READ;
res = tb_cfg_request_sync(ctl, req, timeout_msec);
tb_cfg_request_put(req);
if (res.err)
return res.err;
memcpy(buffer, &reply.data, 4 * length);
return 0;
}
static int dma_port_write(struct tb_ctl *ctl, const void *buffer, u64 route,
u32 port, u32 offset, u32 length, int timeout_msec)
{
struct cfg_write_pkg request = {
.header = tb_cfg_make_header(route),
.addr = {
.seq = 1,
.port = port,
.space = TB_CFG_PORT,
.offset = offset,
.length = length,
},
};
struct tb_cfg_request *req;
struct cfg_read_pkg reply;
struct tb_cfg_result res;
memcpy(&request.data, buffer, length * 4);
req = tb_cfg_request_alloc();
if (!req)
return -ENOMEM;
req->match = dma_port_match;
req->copy = dma_port_copy;
req->request = &request;
req->request_size = 12 + 4 * length;
req->request_type = TB_CFG_PKG_WRITE;
req->response = &reply;
req->response_size = sizeof(reply);
req->response_type = TB_CFG_PKG_WRITE;
res = tb_cfg_request_sync(ctl, req, timeout_msec);
tb_cfg_request_put(req);
return res.err;
}
static int dma_find_port(struct tb_switch *sw)
{
static const int ports[] = { 3, 5, 7 };
int i;
/*
* The DMA (NHI) port is either 3, 5 or 7 depending on the
* controller. Try all of them.
*/
for (i = 0; i < ARRAY_SIZE(ports); i++) {
u32 type;
int ret;
ret = dma_port_read(sw->tb->ctl, &type, tb_route(sw), ports[i],
2, 1, DMA_PORT_TIMEOUT);
if (!ret && (type & 0xffffff) == TB_TYPE_NHI)
return ports[i];
}
return -ENODEV;
}
/**
* dma_port_alloc() - Finds DMA control port from a switch pointed by route
* @sw: Switch from where find the DMA port
*
* Function checks if the switch NHI port supports DMA configuration
* based mailbox capability and if it does, allocates and initializes
* DMA port structure. Returns %NULL if the capabity was not found.
*
* The DMA control port is functional also when the switch is in safe
* mode.
*/
struct tb_dma_port *dma_port_alloc(struct tb_switch *sw)
{
struct tb_dma_port *dma;
int port;
port = dma_find_port(sw);
if (port < 0)
return NULL;
dma = kzalloc(sizeof(*dma), GFP_KERNEL);
if (!dma)
return NULL;
dma->buf = kmalloc_array(MAIL_DATA_DWORDS, sizeof(u32), GFP_KERNEL);
if (!dma->buf) {
kfree(dma);
return NULL;
}
dma->sw = sw;
dma->port = port;
dma->base = DMA_PORT_CAP;
return dma;
}
/**
* dma_port_free() - Release DMA control port structure
* @dma: DMA control port
*/
void dma_port_free(struct tb_dma_port *dma)
{
if (dma) {
kfree(dma->buf);
kfree(dma);
}
}
static int dma_port_wait_for_completion(struct tb_dma_port *dma,
unsigned int timeout)
{
unsigned long end = jiffies + msecs_to_jiffies(timeout);
struct tb_switch *sw = dma->sw;
do {
int ret;
u32 in;
ret = dma_port_read(sw->tb->ctl, &in, tb_route(sw), dma->port,
dma->base + MAIL_IN, 1, 50);
if (ret) {
if (ret != -ETIMEDOUT)
return ret;
} else if (!(in & MAIL_IN_OP_REQUEST)) {
return 0;
}
usleep_range(50, 100);
} while (time_before(jiffies, end));
return -ETIMEDOUT;
}
static int status_to_errno(u32 status)
{
switch (status & MAIL_OUT_STATUS_MASK) {
case MAIL_OUT_STATUS_COMPLETED:
return 0;
case MAIL_OUT_STATUS_ERR_AUTH:
return -EINVAL;
case MAIL_OUT_STATUS_ERR_ACCESS:
return -EACCES;
}
return -EIO;
}
static int dma_port_request(struct tb_dma_port *dma, u32 in,
unsigned int timeout)
{
struct tb_switch *sw = dma->sw;
u32 out;
int ret;
ret = dma_port_write(sw->tb->ctl, &in, tb_route(sw), dma->port,
dma->base + MAIL_IN, 1, DMA_PORT_TIMEOUT);
if (ret)
return ret;
ret = dma_port_wait_for_completion(dma, timeout);
if (ret)
return ret;
ret = dma_port_read(sw->tb->ctl, &out, tb_route(sw), dma->port,
dma->base + MAIL_OUT, 1, DMA_PORT_TIMEOUT);
if (ret)
return ret;
return status_to_errno(out);
}
static int dma_port_flash_read_block(void *data, unsigned int dwaddress,
void *buf, size_t dwords)
{
struct tb_dma_port *dma = data;
struct tb_switch *sw = dma->sw;
int ret;
u32 in;
in = MAIL_IN_CMD_FLASH_READ << MAIL_IN_CMD_SHIFT;
if (dwords < MAIL_DATA_DWORDS)
in |= (dwords << MAIL_IN_DWORDS_SHIFT) & MAIL_IN_DWORDS_MASK;
in |= (dwaddress << MAIL_IN_ADDRESS_SHIFT) & MAIL_IN_ADDRESS_MASK;
in |= MAIL_IN_OP_REQUEST;
ret = dma_port_request(dma, in, DMA_PORT_TIMEOUT);
if (ret)
return ret;
return dma_port_read(sw->tb->ctl, buf, tb_route(sw), dma->port,
dma->base + MAIL_DATA, dwords, DMA_PORT_TIMEOUT);
}
static int dma_port_flash_write_block(void *data, unsigned int dwaddress,
const void *buf, size_t dwords)
{
struct tb_dma_port *dma = data;
struct tb_switch *sw = dma->sw;
int ret;
u32 in;
/* Write the block to MAIL_DATA registers */
ret = dma_port_write(sw->tb->ctl, buf, tb_route(sw), dma->port,
dma->base + MAIL_DATA, dwords, DMA_PORT_TIMEOUT);
if (ret)
return ret;
in = MAIL_IN_CMD_FLASH_WRITE << MAIL_IN_CMD_SHIFT;
/* CSS header write is always done to the same magic address */
if (dwaddress >= DMA_PORT_CSS_ADDRESS)
in |= MAIL_IN_CSS;
in |= ((dwords - 1) << MAIL_IN_DWORDS_SHIFT) & MAIL_IN_DWORDS_MASK;
in |= (dwaddress << MAIL_IN_ADDRESS_SHIFT) & MAIL_IN_ADDRESS_MASK;
in |= MAIL_IN_OP_REQUEST;
return dma_port_request(dma, in, DMA_PORT_TIMEOUT);
}
/**
* dma_port_flash_read() - Read from active flash region
* @dma: DMA control port
* @address: Address relative to the start of active region
* @buf: Buffer where the data is read
* @size: Size of the buffer
*/
int dma_port_flash_read(struct tb_dma_port *dma, unsigned int address,
void *buf, size_t size)
{
return tb_nvm_read_data(address, buf, size, DMA_PORT_RETRIES,
dma_port_flash_read_block, dma);
}
/**
* dma_port_flash_write() - Write to non-active flash region
* @dma: DMA control port
* @address: Address relative to the start of non-active region
* @buf: Data to write
* @size: Size of the buffer
*
* Writes block of data to the non-active flash region of the switch. If
* the address is given as %DMA_PORT_CSS_ADDRESS the block is written
* using CSS command.
*/
int dma_port_flash_write(struct tb_dma_port *dma, unsigned int address,
const void *buf, size_t size)
{
if (address >= DMA_PORT_CSS_ADDRESS && size > DMA_PORT_CSS_MAX_SIZE)
return -E2BIG;
return tb_nvm_write_data(address, buf, size, DMA_PORT_RETRIES,
dma_port_flash_write_block, dma);
}
/**
* dma_port_flash_update_auth() - Starts flash authenticate cycle
* @dma: DMA control port
*
* Starts the flash update authentication cycle. If the image in the
* non-active area was valid, the switch starts upgrade process where
* active and non-active area get swapped in the end. Caller should call
* dma_port_flash_update_auth_status() to get status of this command.
* This is because if the switch in question is root switch the
* thunderbolt host controller gets reset as well.
*/
int dma_port_flash_update_auth(struct tb_dma_port *dma)
{
u32 in;
in = MAIL_IN_CMD_FLASH_UPDATE_AUTH << MAIL_IN_CMD_SHIFT;
in |= MAIL_IN_OP_REQUEST;
return dma_port_request(dma, in, 150);
}
/**
* dma_port_flash_update_auth_status() - Reads status of update auth command
* @dma: DMA control port
* @status: Status code of the operation
*
* The function checks if there is status available from the last update
* auth command. Returns %0 if there is no status and no further
* action is required. If there is status, %1 is returned instead and
* @status holds the failure code.
*
* Negative return means there was an error reading status from the
* switch.
*/
int dma_port_flash_update_auth_status(struct tb_dma_port *dma, u32 *status)
{
struct tb_switch *sw = dma->sw;
u32 out, cmd;
int ret;
ret = dma_port_read(sw->tb->ctl, &out, tb_route(sw), dma->port,
dma->base + MAIL_OUT, 1, DMA_PORT_TIMEOUT);
if (ret)
return ret;
/* Check if the status relates to flash update auth */
cmd = (out & MAIL_OUT_STATUS_CMD_MASK) >> MAIL_OUT_STATUS_CMD_SHIFT;
if (cmd == MAIL_IN_CMD_FLASH_UPDATE_AUTH) {
if (status)
*status = out & MAIL_OUT_STATUS_MASK;
/* Reset is needed in any case */
return 1;
}
return 0;
}
/**
* dma_port_power_cycle() - Power cycles the switch
* @dma: DMA control port
*
* Triggers power cycle to the switch.
*/
int dma_port_power_cycle(struct tb_dma_port *dma)
{
u32 in;
in = MAIL_IN_CMD_POWER_CYCLE << MAIL_IN_CMD_SHIFT;
in |= MAIL_IN_OP_REQUEST;
return dma_port_request(dma, in, 150);
}
