blob: f93a160d8d051592d2835934e6e35eb8da39d4f2 [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause
/*
* Copyright(c) 2015, 2016 Intel Corporation.
*/
#include <linux/delay.h>
#include "hfi.h"
#include "common.h"
#include "eprom.h"
/*
* The EPROM is logically divided into three partitions:
* partition 0: the first 128K, visible from PCI ROM BAR
* partition 1: 4K config file (sector size)
* partition 2: the rest
*/
#define P0_SIZE (128 * 1024)
#define P1_SIZE (4 * 1024)
#define P1_START P0_SIZE
#define P2_START (P0_SIZE + P1_SIZE)
/* controller page size, in bytes */
#define EP_PAGE_SIZE 256
#define EP_PAGE_MASK (EP_PAGE_SIZE - 1)
#define EP_PAGE_DWORDS (EP_PAGE_SIZE / sizeof(u32))
/* controller commands */
#define CMD_SHIFT 24
#define CMD_NOP (0)
#define CMD_READ_DATA(addr) ((0x03 << CMD_SHIFT) | addr)
#define CMD_RELEASE_POWERDOWN_NOID ((0xab << CMD_SHIFT))
/* controller interface speeds */
#define EP_SPEED_FULL 0x2 /* full speed */
/*
* How long to wait for the EPROM to become available, in ms.
* The spec 32 Mb EPROM takes around 40s to erase then write.
* Double it for safety.
*/
#define EPROM_TIMEOUT 80000 /* ms */
/*
* Read a 256 byte (64 dword) EPROM page.
* All callers have verified the offset is at a page boundary.
*/
static void read_page(struct hfi1_devdata *dd, u32 offset, u32 *result)
{
int i;
write_csr(dd, ASIC_EEP_ADDR_CMD, CMD_READ_DATA(offset));
for (i = 0; i < EP_PAGE_DWORDS; i++)
result[i] = (u32)read_csr(dd, ASIC_EEP_DATA);
write_csr(dd, ASIC_EEP_ADDR_CMD, CMD_NOP); /* close open page */
}
/*
* Read length bytes starting at offset from the start of the EPROM.
*/
static int read_length(struct hfi1_devdata *dd, u32 start, u32 len, void *dest)
{
u32 buffer[EP_PAGE_DWORDS];
u32 end;
u32 start_offset;
u32 read_start;
u32 bytes;
if (len == 0)
return 0;
end = start + len;
/*
* Make sure the read range is not outside of the controller read
* command address range. Note that '>' is correct below - the end
* of the range is OK if it stops at the limit, but no higher.
*/
if (end > (1 << CMD_SHIFT))
return -EINVAL;
/* read the first partial page */
start_offset = start & EP_PAGE_MASK;
if (start_offset) {
/* partial starting page */
/* align and read the page that contains the start */
read_start = start & ~EP_PAGE_MASK;
read_page(dd, read_start, buffer);
/* the rest of the page is available data */
bytes = EP_PAGE_SIZE - start_offset;
if (len <= bytes) {
/* end is within this page */
memcpy(dest, (u8 *)buffer + start_offset, len);
return 0;
}
memcpy(dest, (u8 *)buffer + start_offset, bytes);
start += bytes;
len -= bytes;
dest += bytes;
}
/* start is now page aligned */
/* read whole pages */
while (len >= EP_PAGE_SIZE) {
read_page(dd, start, buffer);
memcpy(dest, buffer, EP_PAGE_SIZE);
start += EP_PAGE_SIZE;
len -= EP_PAGE_SIZE;
dest += EP_PAGE_SIZE;
}
/* read the last partial page */
if (len) {
read_page(dd, start, buffer);
memcpy(dest, buffer, len);
}
return 0;
}
/*
* Initialize the EPROM handler.
*/
int eprom_init(struct hfi1_devdata *dd)
{
int ret = 0;
/* only the discrete chip has an EPROM */
if (dd->pcidev->device != PCI_DEVICE_ID_INTEL0)
return 0;
/*
* It is OK if both HFIs reset the EPROM as long as they don't
* do it at the same time.
*/
ret = acquire_chip_resource(dd, CR_EPROM, EPROM_TIMEOUT);
if (ret) {
dd_dev_err(dd,
"%s: unable to acquire EPROM resource, no EPROM support\n",
__func__);
goto done_asic;
}
/* reset EPROM to be sure it is in a good state */
/* set reset */
write_csr(dd, ASIC_EEP_CTL_STAT, ASIC_EEP_CTL_STAT_EP_RESET_SMASK);
/* clear reset, set speed */
write_csr(dd, ASIC_EEP_CTL_STAT,
EP_SPEED_FULL << ASIC_EEP_CTL_STAT_RATE_SPI_SHIFT);
/* wake the device with command "release powerdown NoID" */
write_csr(dd, ASIC_EEP_ADDR_CMD, CMD_RELEASE_POWERDOWN_NOID);
dd->eprom_available = true;
release_chip_resource(dd, CR_EPROM);
done_asic:
return ret;
}
/* magic character sequence that begins an image */
#define IMAGE_START_MAGIC "APO="
/* magic character sequence that might trail an image */
#define IMAGE_TRAIL_MAGIC "egamiAPO"
/* EPROM file types */
#define HFI1_EFT_PLATFORM_CONFIG 2
/* segment size - 128 KiB */
#define SEG_SIZE (128 * 1024)
struct hfi1_eprom_footer {
u32 oprom_size; /* size of the oprom, in bytes */
u16 num_table_entries;
u16 version; /* version of this footer */
u32 magic; /* must be last */
};
struct hfi1_eprom_table_entry {
u32 type; /* file type */
u32 offset; /* file offset from start of EPROM */
u32 size; /* file size, in bytes */
};
/*
* Calculate the max number of table entries that will fit within a directory
* buffer of size 'dir_size'.
*/
#define MAX_TABLE_ENTRIES(dir_size) \
(((dir_size) - sizeof(struct hfi1_eprom_footer)) / \
sizeof(struct hfi1_eprom_table_entry))
#define DIRECTORY_SIZE(n) (sizeof(struct hfi1_eprom_footer) + \
(sizeof(struct hfi1_eprom_table_entry) * (n)))
#define MAGIC4(a, b, c, d) ((d) << 24 | (c) << 16 | (b) << 8 | (a))
#define FOOTER_MAGIC MAGIC4('e', 'p', 'r', 'm')
#define FOOTER_VERSION 1
/*
* Read all of partition 1. The actual file is at the front. Adjust
* the returned size if a trailing image magic is found.
*/
static int read_partition_platform_config(struct hfi1_devdata *dd, void **data,
u32 *size)
{
void *buffer;
void *p;
u32 length;
int ret;
buffer = kmalloc(P1_SIZE, GFP_KERNEL);
if (!buffer)
return -ENOMEM;
ret = read_length(dd, P1_START, P1_SIZE, buffer);
if (ret) {
kfree(buffer);
return ret;
}
/* config partition is valid only if it starts with IMAGE_START_MAGIC */
if (memcmp(buffer, IMAGE_START_MAGIC, strlen(IMAGE_START_MAGIC))) {
kfree(buffer);
return -ENOENT;
}
/* scan for image magic that may trail the actual data */
p = strnstr(buffer, IMAGE_TRAIL_MAGIC, P1_SIZE);
if (p)
length = p - buffer;
else
length = P1_SIZE;
*data = buffer;
*size = length;
return 0;
}
/*
* The segment magic has been checked. There is a footer and table of
* contents present.
*
* directory is a u32 aligned buffer of size EP_PAGE_SIZE.
*/
static int read_segment_platform_config(struct hfi1_devdata *dd,
void *directory, void **data, u32 *size)
{
struct hfi1_eprom_footer *footer;
struct hfi1_eprom_table_entry *table;
struct hfi1_eprom_table_entry *entry;
void *buffer = NULL;
void *table_buffer = NULL;
int ret, i;
u32 directory_size;
u32 seg_base, seg_offset;
u32 bytes_available, ncopied, to_copy;
/* the footer is at the end of the directory */
footer = (struct hfi1_eprom_footer *)
(directory + EP_PAGE_SIZE - sizeof(*footer));
/* make sure the structure version is supported */
if (footer->version != FOOTER_VERSION)
return -EINVAL;
/* oprom size cannot be larger than a segment */
if (footer->oprom_size >= SEG_SIZE)
return -EINVAL;
/* the file table must fit in a segment with the oprom */
if (footer->num_table_entries >
MAX_TABLE_ENTRIES(SEG_SIZE - footer->oprom_size))
return -EINVAL;
/* find the file table start, which precedes the footer */
directory_size = DIRECTORY_SIZE(footer->num_table_entries);
if (directory_size <= EP_PAGE_SIZE) {
/* the file table fits into the directory buffer handed in */
table = (struct hfi1_eprom_table_entry *)
(directory + EP_PAGE_SIZE - directory_size);
} else {
/* need to allocate and read more */
table_buffer = kmalloc(directory_size, GFP_KERNEL);
if (!table_buffer)
return -ENOMEM;
ret = read_length(dd, SEG_SIZE - directory_size,
directory_size, table_buffer);
if (ret)
goto done;
table = table_buffer;
}
/* look for the platform configuration file in the table */
for (entry = NULL, i = 0; i < footer->num_table_entries; i++) {
if (table[i].type == HFI1_EFT_PLATFORM_CONFIG) {
entry = &table[i];
break;
}
}
if (!entry) {
ret = -ENOENT;
goto done;
}
/*
* Sanity check on the configuration file size - it should never
* be larger than 4 KiB.
*/
if (entry->size > (4 * 1024)) {
dd_dev_err(dd, "Bad configuration file size 0x%x\n",
entry->size);
ret = -EINVAL;
goto done;
}
/* check for bogus offset and size that wrap when added together */
if (entry->offset + entry->size < entry->offset) {
dd_dev_err(dd,
"Bad configuration file start + size 0x%x+0x%x\n",
entry->offset, entry->size);
ret = -EINVAL;
goto done;
}
/* allocate the buffer to return */
buffer = kmalloc(entry->size, GFP_KERNEL);
if (!buffer) {
ret = -ENOMEM;
goto done;
}
/*
* Extract the file by looping over segments until it is fully read.
*/
seg_offset = entry->offset % SEG_SIZE;
seg_base = entry->offset - seg_offset;
ncopied = 0;
while (ncopied < entry->size) {
/* calculate data bytes available in this segment */
/* start with the bytes from the current offset to the end */
bytes_available = SEG_SIZE - seg_offset;
/* subtract off footer and table from segment 0 */
if (seg_base == 0) {
/*
* Sanity check: should not have a starting point
* at or within the directory.
*/
if (bytes_available <= directory_size) {
dd_dev_err(dd,
"Bad configuration file - offset 0x%x within footer+table\n",
entry->offset);
ret = -EINVAL;
goto done;
}
bytes_available -= directory_size;
}
/* calculate bytes wanted */
to_copy = entry->size - ncopied;
/* max out at the available bytes in this segment */
if (to_copy > bytes_available)
to_copy = bytes_available;
/*
* Read from the EPROM.
*
* The sanity check for entry->offset is done in read_length().
* The EPROM offset is validated against what the hardware
* addressing supports. In addition, if the offset is larger
* than the actual EPROM, it silently wraps. It will work
* fine, though the reader may not get what they expected
* from the EPROM.
*/
ret = read_length(dd, seg_base + seg_offset, to_copy,
buffer + ncopied);
if (ret)
goto done;
ncopied += to_copy;
/* set up for next segment */
seg_offset = footer->oprom_size;
seg_base += SEG_SIZE;
}
/* success */
ret = 0;
*data = buffer;
*size = entry->size;
done:
kfree(table_buffer);
if (ret)
kfree(buffer);
return ret;
}
/*
* Read the platform configuration file from the EPROM.
*
* On success, an allocated buffer containing the data and its size are
* returned. It is up to the caller to free this buffer.
*
* Return value:
* 0 - success
* -ENXIO - no EPROM is available
* -EBUSY - not able to acquire access to the EPROM
* -ENOENT - no recognizable file written
* -ENOMEM - buffer could not be allocated
* -EINVAL - invalid EPROM contentents found
*/
int eprom_read_platform_config(struct hfi1_devdata *dd, void **data, u32 *size)
{
u32 directory[EP_PAGE_DWORDS]; /* aligned buffer */
int ret;
if (!dd->eprom_available)
return -ENXIO;
ret = acquire_chip_resource(dd, CR_EPROM, EPROM_TIMEOUT);
if (ret)
return -EBUSY;
/* read the last page of the segment for the EPROM format magic */
ret = read_length(dd, SEG_SIZE - EP_PAGE_SIZE, EP_PAGE_SIZE, directory);
if (ret)
goto done;
/* last dword of the segment contains a magic value */
if (directory[EP_PAGE_DWORDS - 1] == FOOTER_MAGIC) {
/* segment format */
ret = read_segment_platform_config(dd, directory, data, size);
} else {
/* partition format */
ret = read_partition_platform_config(dd, data, size);
}
done:
release_chip_resource(dd, CR_EPROM);
return ret;
}