From 107ffbc521b07f22c2e8d1c5fce39766c265c02c Mon Sep 17 00:00:00 2001 From: Dean Luick Date: Fri, 30 Sep 2016 04:41:40 -0700 Subject: [PATCH] IB/hfi1: Add ability to read platform config from the EPROM Add a function to read the platform configuration file from the EPROM. Reviewed-by: Easwar Hariharan Signed-off-by: Dean Luick Signed-off-by: Dennis Dalessandro Signed-off-by: Doug Ledford --- drivers/infiniband/hw/hfi1/eprom.c | 82 ++++++++++++++++++++++++++++++++++++++ drivers/infiniband/hw/hfi1/eprom.h | 2 + 2 files changed, 84 insertions(+) diff --git a/drivers/infiniband/hw/hfi1/eprom.c b/drivers/infiniband/hw/hfi1/eprom.c index 30ecd94..e70c223 100644 --- a/drivers/infiniband/hw/hfi1/eprom.c +++ b/drivers/infiniband/hw/hfi1/eprom.c @@ -203,3 +203,85 @@ int eprom_init(struct hfi1_devdata *dd) done_asic: return ret; } + +/* magic character sequence that trails an image */ +#define IMAGE_TRAIL_MAGIC "egamiAPO" + +/* + * 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; + } + + /* 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; +} + +/* + * 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 + */ +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 P0 for the EPROM format magic */ + ret = read_length(dd, P1_START - 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) { + /* 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; +} diff --git a/drivers/infiniband/hw/hfi1/eprom.h b/drivers/infiniband/hw/hfi1/eprom.h index b7ac9ce..e774184 100644 --- a/drivers/infiniband/hw/hfi1/eprom.h +++ b/drivers/infiniband/hw/hfi1/eprom.h @@ -48,3 +48,5 @@ struct hfi1_devdata; int eprom_init(struct hfi1_devdata *dd); +int eprom_read_platform_config(struct hfi1_devdata *dd, void **buf_ret, + u32 *size_ret); -- 2.7.4