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IB/hfi1: Read new EPROM format

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Add the ability to read the new EPROM format.

Reviewed-by: Easwar Hariharan <easwar.hariharan@intel.com>
Signed-off-by: Dean Luick <dean.luick@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
This commit is contained in:
Dean Luick 2016-12-07 19:32:15 -08:00 committed by Doug Ledford
parent 8af8d2970e
commit 62aeddbf28
1 changed files with 203 additions and 8 deletions
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211
drivers/infiniband/hw/hfi1/eprom.c
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@ -207,6 +207,40 @@ done_asic:
/* magic character sequence that trails 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.
@ -241,6 +275,167 @@ static int read_partition_platform_config(struct hfi1_devdata *dd, void **data,
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.
*
@ -253,6 +448,7 @@ static int read_partition_platform_config(struct hfi1_devdata *dd, void **data,
* -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)
{
@ -266,21 +462,20 @@ int eprom_read_platform_config(struct hfi1_devdata *dd, void **data, u32 *size)
if (ret)
return -EBUSY;
/* read the last page of P0 for the EPROM format magic */
ret = read_length(dd, P1_START - EP_PAGE_SIZE, EP_PAGE_SIZE, directory);
/* 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 P0 contains a magic indicator */
if (directory[EP_PAGE_DWORDS - 1] == 0) {
/* 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);
goto done;
}
/* nothing recognized */
ret = -ENOENT;
done:
release_chip_resource(dd, CR_EPROM);
return ret;