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|
// SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later
/* Copyright 2017-2018 IBM Corp. */
#define pr_fmt(fmt) "MBOX-FLASH: " fmt
#define _GNU_SOURCE
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <skiboot.h>
#include <inttypes.h>
#include <timebase.h>
#include <timer.h>
#include <libflash/libflash.h>
#include <libflash/mbox-flash.h>
#include <lpc.h>
#include <lpc-mbox.h>
#include <ccan/container_of/container_of.h>
#ifndef __SKIBOOT__
#ifndef __TEST__
#error "This libflash backend must be compiled with skiboot"
#endif
#endif
/* Same technique as BUILD_BUG_ON from linux */
#define CHECK_HANDLER_SIZE(handlers) ((void)sizeof(char[1 - 2*!!(ARRAY_SIZE(handlers) != (MBOX_COMMAND_COUNT + 1))]))
#define MBOX_DEFAULT_TIMEOUT 3 /* seconds */
#define MSG_CREATE(init_command) { .command = init_command }
struct mbox_flash_data;
typedef void (mbox_handler)(struct mbox_flash_data *, struct bmc_mbox_msg *);
struct lpc_window {
uint32_t lpc_addr; /* Offset into LPC space */
uint32_t cur_pos; /* Current position of the window in the flash */
uint32_t size; /* Size of the window into the flash */
bool open;
};
struct mbox_flash_data {
int version;
uint16_t timeout;
uint32_t shift;
struct lpc_window read;
struct lpc_window write;
struct blocklevel_device bl;
uint32_t total_size;
uint32_t erase_granule;
int rc;
bool reboot;
bool pause;
bool busy;
bool ack;
mbox_handler **handlers;
};
static mbox_handler mbox_flash_do_nop;
static mbox_handler mbox_flash_do_illegal;
/* Version 1, 2, 3 compatible */
static mbox_handler mbox_flash_do_get_mbox_info;
/* Version 2 and 3 compatible */
static mbox_handler mbox_flash_do_get_flash_info;
static mbox_handler mbox_flash_do_get_flash_info_v1;
/* Version 2 and 3 compatible */
static mbox_handler mbox_flash_do_create_read_window;
static mbox_handler mbox_flash_do_create_read_window_v1;
/* Version 2 and 3 compatible */
static mbox_handler mbox_flash_do_create_write_window;
static mbox_handler mbox_flash_do_create_write_window_v1;
/* Version 1, 2, 3 compatible */
static mbox_handler mbox_flash_do_close_window;
/* Plus one, commands start at 1 */
static mbox_handler *handlers_v3[] = {
NULL,
&mbox_flash_do_nop,
&mbox_flash_do_get_mbox_info,
&mbox_flash_do_get_flash_info,
&mbox_flash_do_create_read_window,
&mbox_flash_do_close_window,
&mbox_flash_do_create_write_window,
&mbox_flash_do_nop,
&mbox_flash_do_nop,
&mbox_flash_do_nop,
&mbox_flash_do_nop,
&mbox_flash_do_nop,
&mbox_flash_do_nop
};
/* Plus one, commands start at 1 */
static mbox_handler *handlers_v2[] = {
NULL,
&mbox_flash_do_nop,
&mbox_flash_do_get_mbox_info,
&mbox_flash_do_get_flash_info,
&mbox_flash_do_create_read_window,
&mbox_flash_do_close_window,
&mbox_flash_do_create_write_window,
&mbox_flash_do_nop,
&mbox_flash_do_nop,
&mbox_flash_do_nop,
&mbox_flash_do_nop,
&mbox_flash_do_illegal,
&mbox_flash_do_illegal
};
/*
* Plus one, commands start at 1.
* V2 adds a command so there should never be a response for the last
* command.
* Ensure we print an error message with mbox_flash_do_illegal().
*/
static mbox_handler *handlers_v1[] = {
NULL,
&mbox_flash_do_nop,
&mbox_flash_do_get_mbox_info,
&mbox_flash_do_get_flash_info_v1,
&mbox_flash_do_create_read_window_v1,
&mbox_flash_do_close_window,
&mbox_flash_do_create_write_window_v1,
&mbox_flash_do_nop,
&mbox_flash_do_nop,
&mbox_flash_do_nop,
&mbox_flash_do_illegal,
&mbox_flash_do_illegal,
&mbox_flash_do_illegal
};
static void mbox_flash_callback(struct bmc_mbox_msg *msg, void *priv);
static void mbox_flash_attn(uint8_t attn, void *priv);
static int protocol_init(struct mbox_flash_data *mbox_flash, uint8_t shift);
static int lpc_window_read(struct mbox_flash_data *mbox_flash, uint32_t pos,
void *buf, uint32_t len)
{
uint32_t off = mbox_flash->read.lpc_addr + (pos - mbox_flash->read.cur_pos);
int rc;
prlog(PR_TRACE, "Reading at 0x%08x for 0x%08x offset: 0x%08x\n",
pos, len, off);
while(len) {
uint32_t chunk;
uint32_t dat;
/* XXX: make this read until it's aligned */
if (len > 3 && !(off & 3)) {
rc = lpc_read(OPAL_LPC_FW, off, &dat, 4);
if (!rc) {
/*
* lpc_read swaps to CPU endian but it's not
* really a 32-bit value, so convert back.
*/
*(__be32 *)buf = cpu_to_be32(dat);
}
chunk = 4;
} else {
rc = lpc_read(OPAL_LPC_FW, off, &dat, 1);
if (!rc)
*(uint8_t *)buf = dat;
chunk = 1;
}
if (rc) {
prlog(PR_ERR, "lpc_read failure %d to FW 0x%08x\n", rc, off);
return rc;
}
len -= chunk;
off += chunk;
buf += chunk;
}
return 0;
}
static int lpc_window_write(struct mbox_flash_data *mbox_flash, uint32_t pos,
const void *buf, uint32_t len)
{
uint32_t off = mbox_flash->write.lpc_addr + (pos - mbox_flash->write.cur_pos);
int rc;
prlog(PR_TRACE, "Writing at 0x%08x for 0x%08x offset: 0x%08x\n",
pos, len, off);
while(len) {
uint32_t chunk;
if (len > 3 && !(off & 3)) {
/* endian swap: see lpc_window_write */
uint32_t dat = be32_to_cpu(*(__be32 *)buf);
rc = lpc_write(OPAL_LPC_FW, off, dat, 4);
chunk = 4;
} else {
uint8_t dat = *(uint8_t *)buf;
rc = lpc_write(OPAL_LPC_FW, off, dat, 1);
chunk = 1;
}
if (rc) {
prlog(PR_ERR, "lpc_write failure %d to FW 0x%08x\n", rc, off);
return rc;
}
len -= chunk;
off += chunk;
buf += chunk;
}
return 0;
}
static uint64_t mbox_flash_mask(struct mbox_flash_data *mbox_flash)
{
return (1ULL << mbox_flash->shift) - 1;
}
__unused static uint8_t msg_get_u8(struct bmc_mbox_msg *msg, int i)
{
return msg->args[i];
}
static void msg_put_u8(struct bmc_mbox_msg *msg, int i, uint8_t val)
{
msg->args[i] = val;
}
static uint16_t msg_get_u16(struct bmc_mbox_msg *msg, int i)
{
return le16_to_cpu(*(__le16 *)(&msg->args[i]));
}
static void msg_put_u16(struct bmc_mbox_msg *msg, int i, uint16_t val)
{
__le16 tmp = cpu_to_le16(val);
memcpy(&msg->args[i], &tmp, sizeof(val));
}
static uint32_t msg_get_u32(struct bmc_mbox_msg *msg, int i)
{
return le32_to_cpu(*(__le32 *)(&msg->args[i]));
}
static void msg_put_u32(struct bmc_mbox_msg *msg, int i, uint32_t val)
{
__le32 tmp = cpu_to_le32(val);
memcpy(&msg->args[i], &tmp, sizeof(val));
}
static uint32_t blocks_to_bytes(struct mbox_flash_data *mbox_flash, uint16_t blocks)
{
return blocks << mbox_flash->shift;
}
static uint16_t bytes_to_blocks(struct mbox_flash_data *mbox_flash,
uint32_t bytes)
{
return bytes >> mbox_flash->shift;
}
/*
* The BMC may send is an out of band message to say that it doesn't
* own the flash anymore.
* It guarantees we can still access our (open) windows but it does
* not guarantee their contents until it clears the bit without
* sending us a corresponding bit to say that the windows are bad
* first.
* Since this is all things that will happen in the future, we should
* not perform any calls speculatively as its almost impossible to
* rewind.
*/
static bool is_paused(struct mbox_flash_data *mbox_flash)
{
return mbox_flash->pause;
}
/*
* After a read or a write it is wise to check that the window we just
* read/write to/from is still valid otherwise it is possible some of
* the data didn't make it.
* This check is an optimisation as we'll close all our windows on any
* notification from the BMC that the windows are bad. See the above
* comment about is_paused().
* A foolproof (but much closer) method of validating reads/writes
* would be to attempt to close the window, if that fails then we can
* be sure that the read/write was no good.
*/
static bool is_valid(struct mbox_flash_data *mbox_flash, struct lpc_window *win)
{
return !is_paused(mbox_flash) && win->open;
}
/*
* Check if we've received a BMC reboot notification.
* The strategy is to check on entry to mbox-flash and return a
* failure accordingly. Races will be handled by the fact that the BMC
* won't respond so timeouts will occur. As an added precaution
* msg_send() checks right before sending a message (to make the race
* as small as possible to avoid needless timeouts).
*/
static bool is_reboot(struct mbox_flash_data *mbox_flash)
{
return mbox_flash->reboot;
}
static int msg_send(struct mbox_flash_data *mbox_flash, struct bmc_mbox_msg *msg,
unsigned int timeout_sec)
{
if (is_reboot(mbox_flash))
return FLASH_ERR_AGAIN;
mbox_flash->busy = true;
mbox_flash->rc = 0;
return bmc_mbox_enqueue(msg, timeout_sec);
}
static int wait_for_bmc(struct mbox_flash_data *mbox_flash, unsigned int timeout_sec)
{
unsigned long last = 1, start = tb_to_secs(mftb());
prlog(PR_TRACE, "Waiting for BMC\n");
while (mbox_flash->busy && timeout_sec > last) {
long now = tb_to_secs(mftb());
if (now - start > last) {
if (last < timeout_sec / 2)
prlog(PR_TRACE, "Been waiting for the BMC for %lu secs\n", last);
else
prlog(PR_ERR, "BMC NOT RESPONDING %lu second wait\n", last);
last++;
}
/*
* Both functions are important.
* Well time_wait_ms() relaxes the spin... so... its nice
*/
check_timers(false);
if (mbox_flash->busy)
time_wait_ms(MBOX_DEFAULT_POLL_MS);
asm volatile ("" ::: "memory");
}
if (mbox_flash->busy) {
prlog(PR_ERR, "Timeout waiting for BMC\n");
mbox_flash->busy = false;
return MBOX_R_TIMEOUT;
}
return mbox_flash->rc;
}
static int mbox_flash_ack(struct mbox_flash_data *mbox_flash, uint8_t reg)
{
struct bmc_mbox_msg msg = MSG_CREATE(MBOX_C_BMC_EVENT_ACK);
int rc;
msg_put_u8(&msg, 0, reg);
/* Clear this first so msg_send() doesn't freak out */
mbox_flash->reboot = false;
/*
* Use a lower timeout - there is strong evidence to suggest the
* BMC won't respond, don't waste time spinning here just have the
* high levels retry when the BMC might be back
*/
rc = msg_send(mbox_flash, &msg, 3);
/* Still need to deal with it, we've only acked it now. */
mbox_flash->reboot = true;
if (rc) {
prlog(PR_ERR, "Failed to enqueue/send BMC MBOX message\n");
return rc;
}
/*
* Use a lower timeout - there is strong evidence to suggest the
* BMC won't respond, don't waste time spinning here just have the
* high levels retry when the BMC might be back
*/
rc = wait_for_bmc(mbox_flash, 3);
if (rc)
prlog(PR_ERR, "Error waiting for BMC\n");
return rc;
}
static int do_acks(struct mbox_flash_data *mbox_flash)
{
int rc;
if (!mbox_flash->ack)
return 0; /* Nothing to do */
rc = mbox_flash_ack(mbox_flash, bmc_mbox_get_attn_reg() & MBOX_ATTN_ACK_MASK);
if (!rc)
mbox_flash->ack = false;
return rc;
}
static void mbox_flash_do_nop(struct mbox_flash_data *mbox_flash __unused,
struct bmc_mbox_msg *msg __unused)
{
}
static void mbox_flash_do_illegal(struct mbox_flash_data *mbox_flash __unused,
struct bmc_mbox_msg *msg __unused)
{
prlog(PR_CRIT, "Got response to unknown message type\n");
}
/* Version 1, 2 and 3 compatible */
static void mbox_flash_do_get_mbox_info(struct mbox_flash_data *mbox_flash,
struct bmc_mbox_msg *msg)
{
mbox_flash->version = msg_get_u8(msg, 0);
switch (mbox_flash->version) {
case 1:
/* Not all version 1 daemons set argument 5 correctly */
mbox_flash->shift = 12; /* Protocol hardcodes to 4K anyway */
mbox_flash->read.size = blocks_to_bytes(mbox_flash, msg_get_u16(msg, 1));
mbox_flash->write.size = blocks_to_bytes(mbox_flash, msg_get_u16(msg, 3));
break;
case 3:
case 2:
mbox_flash->shift = msg_get_u8(msg, 5);
mbox_flash->timeout = msg_get_u16(msg, 6);
if (mbox_flash->timeout == 0)
mbox_flash->timeout = MBOX_DEFAULT_TIMEOUT;
break;
}
/* Callers will handle the case where the version is not known
*
* Here we deliberately ignore the 'default' sizes.
* All windows opened will not provide a hint and we're
* happy to let the BMC figure everything out.
* Future optimisations may use the default size.
*/
}
/* Version 2 and 3 compatible */
static void mbox_flash_do_get_flash_info(struct mbox_flash_data *mbox_flash,
struct bmc_mbox_msg *msg)
{
mbox_flash->total_size = blocks_to_bytes(mbox_flash, msg_get_u16(msg, 0));
mbox_flash->erase_granule = blocks_to_bytes(mbox_flash, msg_get_u16(msg, 2));
}
static void mbox_flash_do_get_flash_info_v1(struct mbox_flash_data *mbox_flash,
struct bmc_mbox_msg *msg)
{
mbox_flash->total_size = msg_get_u32(msg, 0);
mbox_flash->erase_granule = msg_get_u32(msg, 4);
}
/* Version 2 and 3 compatible */
static void mbox_flash_do_create_read_window(struct mbox_flash_data *mbox_flash,
struct bmc_mbox_msg *msg)
{
mbox_flash->read.lpc_addr = blocks_to_bytes(mbox_flash, msg_get_u16(msg, 0));
mbox_flash->read.size = blocks_to_bytes(mbox_flash, msg_get_u16(msg, 2));
mbox_flash->read.cur_pos = blocks_to_bytes(mbox_flash, msg_get_u16(msg, 4));
mbox_flash->read.open = true;
mbox_flash->write.open = false;
}
static void mbox_flash_do_create_read_window_v1(struct mbox_flash_data *mbox_flash,
struct bmc_mbox_msg *msg)
{
mbox_flash->read.lpc_addr = blocks_to_bytes(mbox_flash, msg_get_u16(msg, 0));
mbox_flash->read.open = true;
mbox_flash->write.open = false;
}
/* Version 2 and 3 compatible */
static void mbox_flash_do_create_write_window(struct mbox_flash_data *mbox_flash,
struct bmc_mbox_msg *msg)
{
mbox_flash->write.lpc_addr = blocks_to_bytes(mbox_flash, msg_get_u16(msg, 0));
mbox_flash->write.size = blocks_to_bytes(mbox_flash, msg_get_u16(msg, 2));
mbox_flash->write.cur_pos = blocks_to_bytes(mbox_flash, msg_get_u16(msg, 4));
mbox_flash->write.open = true;
mbox_flash->read.open = false;
}
static void mbox_flash_do_create_write_window_v1(struct mbox_flash_data *mbox_flash,
struct bmc_mbox_msg *msg)
{
mbox_flash->write.lpc_addr = blocks_to_bytes(mbox_flash, msg_get_u16(msg, 0));
mbox_flash->write.open = true;
mbox_flash->read.open = false;
}
/* Version 1 and Version 2 compatible */
static void mbox_flash_do_close_window(struct mbox_flash_data *mbox_flash,
struct bmc_mbox_msg *msg __unused)
{
mbox_flash->read.open = false;
mbox_flash->write.open = false;
}
static int handle_reboot(struct mbox_flash_data *mbox_flash)
{
int rc;
/*
* If the BMC ready bit isn't present then we're basically
* guaranteed to timeout trying to talk to it so just fail
* whatever is trying to happen.
* Importantly, we can't trust that the presence of the bit means
* the daemon is ok - don't assume it is going to respond at all
* from here onwards
*/
if (!(bmc_mbox_get_attn_reg() & MBOX_ATTN_BMC_DAEMON_READY))
return FLASH_ERR_AGAIN;
/* Clear this first so msg_send() doesn't freak out */
mbox_flash->reboot = false;
rc = do_acks(mbox_flash);
if (rc) {
if (rc == MBOX_R_TIMEOUT)
rc = FLASH_ERR_AGAIN;
mbox_flash->reboot = true;
return rc;
}
rc = protocol_init(mbox_flash, 0);
if (rc)
mbox_flash->reboot = true;
return rc;
}
static bool do_delayed_work(struct mbox_flash_data *mbox_flash)
{
return is_paused(mbox_flash) || do_acks(mbox_flash) ||
(is_reboot(mbox_flash) && handle_reboot(mbox_flash));
}
static int mbox_flash_mark_write(struct mbox_flash_data *mbox_flash,
uint64_t pos, uint64_t len, int type)
{
struct bmc_mbox_msg msg = MSG_CREATE(type);
int rc;
if (mbox_flash->version == 1) {
uint32_t start = ALIGN_DOWN(pos, 1 << mbox_flash->shift);
msg_put_u16(&msg, 0, bytes_to_blocks(mbox_flash, pos));
/*
* We need to make sure that we mark dirty until up to atleast
* pos + len.
*/
msg_put_u32(&msg, 2, pos + len - start);
} else {
uint64_t window_pos = pos - mbox_flash->write.cur_pos;
uint16_t start = bytes_to_blocks(mbox_flash, window_pos);
uint16_t end = bytes_to_blocks(mbox_flash,
ALIGN_UP(window_pos + len,
1 << mbox_flash->shift));
msg_put_u16(&msg, 0, start);
msg_put_u16(&msg, 2, end - start); /* Total Length */
}
rc = msg_send(mbox_flash, &msg, mbox_flash->timeout);
if (rc) {
prlog(PR_ERR, "Failed to enqueue/send BMC MBOX message\n");
return rc;
}
rc = wait_for_bmc(mbox_flash, mbox_flash->timeout);
if (rc)
prlog(PR_ERR, "Error waiting for BMC\n");
return rc;
}
static int mbox_flash_dirty(struct mbox_flash_data *mbox_flash, uint64_t pos,
uint64_t len)
{
if (!mbox_flash->write.open) {
prlog(PR_ERR, "Attempting to dirty without an open write window\n");
return FLASH_ERR_DEVICE_GONE;
}
return mbox_flash_mark_write(mbox_flash, pos, len,
MBOX_C_MARK_WRITE_DIRTY);
}
static int mbox_flash_erase(struct mbox_flash_data *mbox_flash, uint64_t pos,
uint64_t len)
{
if (!mbox_flash->write.open) {
prlog(PR_ERR, "Attempting to erase without an open write window\n");
return FLASH_ERR_DEVICE_GONE;
}
return mbox_flash_mark_write(mbox_flash, pos, len,
MBOX_C_MARK_WRITE_ERASED);
}
static int mbox_flash_flush(struct mbox_flash_data *mbox_flash)
{
struct bmc_mbox_msg msg = MSG_CREATE(MBOX_C_WRITE_FLUSH);
int rc;
if (!mbox_flash->write.open) {
prlog(PR_ERR, "Attempting to flush without an open write window\n");
return FLASH_ERR_DEVICE_GONE;
}
rc = msg_send(mbox_flash, &msg, mbox_flash->timeout);
if (rc) {
prlog(PR_ERR, "Failed to enqueue/send BMC MBOX message\n");
return rc;
}
rc = wait_for_bmc(mbox_flash, mbox_flash->timeout);
if (rc)
prlog(PR_ERR, "Error waiting for BMC\n");
return rc;
}
/* Is the current window able perform the complete operation */
static bool mbox_window_valid(struct lpc_window *win, uint64_t pos,
uint64_t len)
{
if (!win->open)
return false;
if (pos < win->cur_pos) /* start */
return false;
if ((pos + len) > (win->cur_pos + win->size)) /* end */
return false;
return true;
}
static int mbox_window_move(struct mbox_flash_data *mbox_flash,
struct lpc_window *win, uint8_t command,
uint64_t pos, uint64_t len, uint64_t *size)
{
struct bmc_mbox_msg msg = MSG_CREATE(command);
int rc;
/* Is the window currently open valid */
if (mbox_window_valid(win, pos, len)) {
*size = len;
return 0;
}
/* V1 needs to remember where it has opened the window, note it
* here.
* If we're running V2 the response to the CREATE_*_WINDOW command
* will overwrite what we've noted here.
*/
win->cur_pos = pos & ~mbox_flash_mask(mbox_flash);
msg_put_u16(&msg, 0, bytes_to_blocks(mbox_flash, pos));
rc = msg_send(mbox_flash, &msg, mbox_flash->timeout);
if (rc) {
prlog(PR_ERR, "Failed to enqueue/send BMC MBOX message\n");
return rc;
}
mbox_flash->read.open = false;
mbox_flash->write.open = false;
rc = wait_for_bmc(mbox_flash, mbox_flash->timeout);
if (rc) {
prlog(PR_ERR, "Error waiting for BMC\n");
return rc;
}
*size = len;
/* Is length past the end of the window? */
if ((pos + len) > (win->cur_pos + win->size))
/* Adjust size to meet current window */
*size = (win->cur_pos + win->size) - pos;
/*
* It doesn't make sense for size to be zero if len isn't zero.
* If this condition happens we're most likely going to spin since
* the caller will likely decerement pos by zero then call this
* again.
* Debateable as to if this should return non zero. At least the
* bug will be obvious from the barf.
*/
if (len != 0 && *size == 0) {
prlog(PR_ERR, "Failed read/write!\n");
prlog(PR_ERR, "Please update your BMC firmware\n");
prlog(PR_ERR, "Move window is indicating size zero!\n");
prlog(PR_ERR, "pos: 0x%" PRIx64 ", len: 0x%" PRIx64 "\n", pos, len);
prlog(PR_ERR, "win pos: 0x%08x win size: 0x%08x\n", win->cur_pos, win->size);
/*
* In practice skiboot gets stuck and this eventually
* brings down the host. Just fail pass the error back
* up and hope someone makes a good decision
*/
return MBOX_R_SYSTEM_ERROR;
}
return rc;
}
static int mbox_flash_write(struct blocklevel_device *bl, uint64_t pos,
const void *buf, uint64_t len)
{
struct mbox_flash_data *mbox_flash;
uint64_t size;
int rc = 0;
/* LPC is only 32bit */
if (pos > UINT_MAX || len > UINT_MAX)
return FLASH_ERR_PARM_ERROR;
mbox_flash = container_of(bl, struct mbox_flash_data, bl);
if (do_delayed_work(mbox_flash))
return FLASH_ERR_AGAIN;
prlog(PR_TRACE, "Flash write at %#" PRIx64 " for %#" PRIx64 "\n", pos, len);
while (len > 0) {
/* Move window and get a new size to read */
rc = mbox_window_move(mbox_flash, &mbox_flash->write,
MBOX_C_CREATE_WRITE_WINDOW, pos, len,
&size);
if (rc)
return rc;
/* Perform the read for this window */
rc = lpc_window_write(mbox_flash, pos, buf, size);
if (rc)
return rc;
rc = mbox_flash_dirty(mbox_flash, pos, size);
if (rc)
return rc;
/*
* Must flush here as changing the window contents
* without flushing entitles the BMC to throw away the
* data. Unlike the read case there isn't a need to explicitly
* validate the window, the flush command will fail if the
* window was compromised.
*/
rc = mbox_flash_flush(mbox_flash);
if (rc)
return rc;
len -= size;
pos += size;
buf += size;
}
return rc;
}
static int mbox_flash_read(struct blocklevel_device *bl, uint64_t pos,
void *buf, uint64_t len)
{
struct mbox_flash_data *mbox_flash;
uint64_t size;
int rc = 0;
/* LPC is only 32bit */
if (pos > UINT_MAX || len > UINT_MAX)
return FLASH_ERR_PARM_ERROR;
mbox_flash = container_of(bl, struct mbox_flash_data, bl);
if (do_delayed_work(mbox_flash))
return FLASH_ERR_AGAIN;
prlog(PR_TRACE, "Flash read at %#" PRIx64 " for %#" PRIx64 "\n", pos, len);
while (len > 0) {
/* Move window and get a new size to read */
rc = mbox_window_move(mbox_flash, &mbox_flash->read,
MBOX_C_CREATE_READ_WINDOW, pos,
len, &size);
if (rc)
return rc;
/* Perform the read for this window */
rc = lpc_window_read(mbox_flash, pos, buf, size);
if (rc)
return rc;
len -= size;
pos += size;
buf += size;
/*
* Ensure my window is still open, if it isn't we can't trust
* what we read
*/
if (!is_valid(mbox_flash, &mbox_flash->read))
return FLASH_ERR_AGAIN;
}
return rc;
}
static bool mbox_flash_reset(struct blocklevel_device *bl)
{
int rc;
struct mbox_flash_data *mbox_flash;
struct bmc_mbox_msg msg = MSG_CREATE(MBOX_C_RESET_STATE);
prlog(PR_NOTICE, "MBOX reset\n");
mbox_flash = container_of(bl, struct mbox_flash_data, bl);
rc = msg_send(mbox_flash, &msg, mbox_flash->timeout);
if (rc) {
prlog(PR_ERR, "Failed to enqueue/send BMC MBOX RESET msg\n");
return false;
}
if (wait_for_bmc(mbox_flash, mbox_flash->timeout)) {
prlog(PR_ERR, "Error waiting for BMC\n");
return false;
}
return true;
}
static int mbox_flash_get_info(struct blocklevel_device *bl, const char **name,
uint64_t *total_size, uint32_t *erase_granule)
{
struct bmc_mbox_msg msg = MSG_CREATE(MBOX_C_GET_FLASH_INFO);
struct mbox_flash_data *mbox_flash;
int rc;
mbox_flash = container_of(bl, struct mbox_flash_data, bl);
if (do_delayed_work(mbox_flash))
return FLASH_ERR_AGAIN;
/*
* We want to avoid runtime mallocs in skiboot. The expected
* behavour to uses of libflash is that one can free() the memory
* returned.
* NULL will do for now.
*/
if (name)
*name = NULL;
mbox_flash->busy = true;
rc = msg_send(mbox_flash, &msg, mbox_flash->timeout);
if (rc) {
prlog(PR_ERR, "Failed to enqueue/send BMC MBOX message\n");
return rc;
}
if (wait_for_bmc(mbox_flash, mbox_flash->timeout)) {
prlog(PR_ERR, "Error waiting for BMC\n");
return rc;
}
mbox_flash->bl.erase_mask = mbox_flash->erase_granule - 1;
if (total_size)
*total_size = mbox_flash->total_size;
if (erase_granule)
*erase_granule = mbox_flash->erase_granule;
return rc;
}
static int mbox_flash_erase_v2(struct blocklevel_device *bl, uint64_t pos,
uint64_t len)
{
struct mbox_flash_data *mbox_flash;
/* LPC is only 32bit */
if (pos > UINT_MAX || len > UINT_MAX)
return FLASH_ERR_PARM_ERROR;
mbox_flash = container_of(bl, struct mbox_flash_data, bl);
prlog(PR_TRACE, "Flash erase at 0x%08x for 0x%08x\n", (u32) pos, (u32) len);
while (len > 0) {
uint64_t size;
int rc;
/* Move window and get a new size to erase */
rc = mbox_window_move(mbox_flash, &mbox_flash->write,
MBOX_C_CREATE_WRITE_WINDOW, pos, len, &size);
if (rc)
return rc;
rc = mbox_flash_erase(mbox_flash, pos, size);
if (rc)
return rc;
/*
* Flush directly, don't mark that region dirty otherwise it
* isn't clear if a write happened there or not
*/
rc = mbox_flash_flush(mbox_flash);
if (rc)
return rc;
len -= size;
pos += size;
}
return 0;
}
static int mbox_flash_erase_v1(struct blocklevel_device *bl __unused,
uint64_t pos __unused, uint64_t len __unused)
{
/*
* We can probably get away with doing nothing.
* TODO: Rethink this, causes interesting behaviour in pflash.
* Users do expect pflash -{e,E} to do something. This is because
* on real flash this would have set that region to all 0xFF but
* really the erase at the blocklevel interface was only designed
* to be "please make this region writeable".
* It may be wise (despite the large performance penalty) to
* actually write all 0xFF here. I'll leave that as an exercise
* for the future.
*/
return 0;
}
/* Called from interrupt handler, don't send any mbox messages */
static void mbox_flash_attn(uint8_t attn, void *priv)
{
struct mbox_flash_data *mbox_flash = priv;
if (attn & MBOX_ATTN_ACK_MASK)
mbox_flash->ack = true;
if (attn & MBOX_ATTN_BMC_REBOOT) {
mbox_flash->reboot = true;
mbox_flash->read.open = false;
mbox_flash->write.open = false;
attn &= ~MBOX_ATTN_BMC_REBOOT;
}
if (attn & MBOX_ATTN_BMC_WINDOW_RESET) {
mbox_flash->read.open = false;
mbox_flash->write.open = false;
attn &= ~MBOX_ATTN_BMC_WINDOW_RESET;
}
if (attn & MBOX_ATTN_BMC_FLASH_LOST) {
mbox_flash->pause = true;
attn &= ~MBOX_ATTN_BMC_FLASH_LOST;
} else {
mbox_flash->pause = false;
}
}
static void mbox_flash_callback(struct bmc_mbox_msg *msg, void *priv)
{
struct mbox_flash_data *mbox_flash = priv;
prlog(PR_TRACE, "BMC OK command %u\n", msg->command);
if (msg->response != MBOX_R_SUCCESS) {
prlog(PR_ERR, "Bad response code from BMC %d\n", msg->response);
mbox_flash->rc = msg->response;
goto out;
}
if (msg->command > MBOX_COMMAND_COUNT) {
prlog(PR_ERR, "Got response to unknown command %02x\n", msg->command);
mbox_flash->rc = -1;
goto out;
}
if (!mbox_flash->handlers[msg->command]) {
prlog(PR_ERR, "Couldn't find handler for message! command: %u, seq: %u\n",
msg->command, msg->seq);
mbox_flash->rc = MBOX_R_SYSTEM_ERROR;
goto out;
}
mbox_flash->rc = 0;
mbox_flash->handlers[msg->command](mbox_flash, msg);
out:
mbox_flash->busy = false;
}
static int protocol_init(struct mbox_flash_data *mbox_flash, uint8_t shift)
{
struct bmc_mbox_msg msg = MSG_CREATE(MBOX_C_GET_MBOX_INFO);
int rc;
mbox_flash->read.open = false;
mbox_flash->write.open = false;
/* Assume V2+ */
mbox_flash->bl.read = &mbox_flash_read;
mbox_flash->bl.write = &mbox_flash_write;
mbox_flash->bl.erase = &mbox_flash_erase_v2;
mbox_flash->bl.get_info = &mbox_flash_get_info;
/* Assume V3 */
mbox_flash->handlers = handlers_v3;
bmc_mbox_register_callback(&mbox_flash_callback, mbox_flash);
bmc_mbox_register_attn(&mbox_flash_attn, mbox_flash);
/*
* For V1 of the protocol this is fixed.
* V2+: The init code will update this
*/
mbox_flash->shift = 12;
/*
* For V1 we'll use this value.
* V2+: The init code (may) update this
*/
mbox_flash->timeout = MBOX_DEFAULT_TIMEOUT;
/*
* Always attempt init with highest version known.
* The GET_MBOX_INFO response will confirm that the other side can
* talk the highest version, we'll update this variable then if
* our highest version is not supported
*/
mbox_flash->version = 3;
negotiate_version:
msg_put_u8(&msg, 0, mbox_flash->version);
msg_put_u8(&msg, 1, shift);
rc = msg_send(mbox_flash, &msg, mbox_flash->timeout);
if (rc) {
prlog(PR_ERR, "Failed to enqueue/send BMC MBOX message\n");
return rc;
}
rc = wait_for_bmc(mbox_flash, mbox_flash->timeout);
if (rc) {
prlog(PR_ERR, "Error waiting for BMC\n");
if (mbox_flash->version > 1) {
mbox_flash->version--;
prlog(PR_INFO, "Retrying MBOX negotiation with BMC"
" with MBOXv%d\n", mbox_flash->version);
goto negotiate_version;
}
return rc;
}
prlog(PR_INFO, "Detected mbox protocol version %d\n", mbox_flash->version);
switch (mbox_flash->version) {
case 1:
mbox_flash->bl.erase = &mbox_flash_erase_v1;
mbox_flash->handlers = handlers_v1;
break;
case 2:
mbox_flash->handlers = handlers_v2;
break;
case 3:
/* Nothing to do we assumed it would be V3 */
break;
default:
/*
* The BMC is can only lower the requested version not do
* anything else. FWIW there is no verion 0.
*/
prlog(PR_CRIT, "Bad version: %u\n", mbox_flash->version);
rc = FLASH_ERR_PARM_ERROR;
}
return rc;
}
int mbox_flash_lock(struct blocklevel_device *bl, uint64_t pos, uint64_t len)
{
struct mbox_flash_data *mbox_flash;
struct bmc_mbox_msg msg = MSG_CREATE(MBOX_C_MARK_LOCKED);
int rc;
/* mbox-flash only talks 32bit for now */
if (pos > UINT_MAX || len > UINT_MAX)
return FLASH_ERR_PARM_ERROR;
/*
* If the region isn't at least 4k aligned and in size then bail
* out, the protocol won't allow for smaller block sizes.
*/
if (pos & ((1 << 12) - 1) || len & ((1 << 12) - 1))
return FLASH_ERR_PARM_ERROR;
mbox_flash = container_of(bl, struct mbox_flash_data, bl);
if ((pos & mbox_flash_mask(mbox_flash)) || (len & mbox_flash_mask(mbox_flash))) {
uint8_t shift = 0;
/*
* The current block size won't work for locking the requested
* region must reinit.
*/
while (!((1 << shift) & pos) && !((1 << shift) & len))
shift++;
prlog(PR_INFO, "Locking flash requires re-init from shift of %d to shift of %d\n",
mbox_flash->shift, shift);
rc = protocol_init(mbox_flash, shift);
if (rc)
return rc;
/*
* The daemon didn't agree with the requested shift - the
* flash won't be able to be locked
*/
if (mbox_flash->shift > shift)
return FLASH_ERR_PARM_ERROR;
}
msg_put_u16(&msg, 0, bytes_to_blocks(mbox_flash, pos));
msg_put_u16(&msg, 2, bytes_to_blocks(mbox_flash, len));
rc = msg_send(mbox_flash, &msg, mbox_flash->timeout);
if (rc) {
prlog(PR_ERR, "Failed to enqueue/send BMC MBOX message\n");
return rc;
}
rc = wait_for_bmc(mbox_flash, mbox_flash->timeout);
if (rc)
prlog(PR_ERR, "Error waiting for BMC\n");
return rc;
}
int mbox_flash_init(struct blocklevel_device **bl)
{
struct mbox_flash_data *mbox_flash;
int rc;
CHECK_HANDLER_SIZE(handlers_v3);
CHECK_HANDLER_SIZE(handlers_v2);
CHECK_HANDLER_SIZE(handlers_v1);
if (!bl)
return FLASH_ERR_PARM_ERROR;
/* XXX: We only support one blocklevel flash device over mbox. If we
* ever support more than one, move this out. The chances of that are
* slim though due to circumstances.
*/
mbox_init();
*bl = NULL;
mbox_flash = zalloc(sizeof(struct mbox_flash_data));
if (!mbox_flash)
return FLASH_ERR_MALLOC_FAILED;
/* Assume V2+ */
mbox_flash->bl.read = &mbox_flash_read;
mbox_flash->bl.write = &mbox_flash_write;
mbox_flash->bl.erase = &mbox_flash_erase_v2;
mbox_flash->bl.get_info = &mbox_flash_get_info;
mbox_flash->bl.exit = &mbox_flash_exit;
if (bmc_mbox_get_attn_reg() & MBOX_ATTN_BMC_REBOOT)
rc = handle_reboot(mbox_flash);
else
rc = protocol_init(mbox_flash, 0);
if (rc) {
free(mbox_flash);
return rc;
}
mbox_flash->bl.keep_alive = 0;
*bl = &(mbox_flash->bl);
return 0;
}
bool mbox_flash_exit(struct blocklevel_device *bl)
{
bool status = true;
struct mbox_flash_data *mbox_flash;
if (bl) {
status = mbox_flash_reset(bl);
mbox_flash = container_of(bl, struct mbox_flash_data, bl);
free(mbox_flash);
}
return status;
}
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