From 27d4dc7116eed98775902627ba61b70e9045e321 Mon Sep 17 00:00:00 2001 From: Vaibhav Jain Date: Wed, 29 Apr 2015 15:47:23 +0530 Subject: cxl: Implement an ioctl to fetch afu card-id, offset-id and mode Given a file descriptor on an afu device, libcxl currently uses the major/minor number obtained from fstat on the fd to construct path to the afu's sysfs directory. However it is possible that rather than using one of the device in /dev/cxl, a kernel driver creates its own device which export generic cxl interface to the userspace. This causes problems with libcxl as it tries to use a wrong major/minor number to construct the sysfs path and fail. So this patch introduces a new ioctl called CXL_IOCTL_GET_AFU_ID on the afu file descriptor to fetch the cxl_afu_id struct that holds the card/offset-id and mode information. These info is then used by libcxl to construct the correct path to the afu sysfs directory. Testing: - Build against pseries be/le configs - Testing with corresponding libcxl changes to verify that it constructs right sysfs path to the afu. Signed-off-by: Vaibhav Jain Acked-by: Ian Munsie Signed-off-by: Michael Ellerman --- include/uapi/misc/cxl.h | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+) (limited to 'include/uapi/misc') diff --git a/include/uapi/misc/cxl.h b/include/uapi/misc/cxl.h index cd6d789b73ec..99a8ca15fe64 100644 --- a/include/uapi/misc/cxl.h +++ b/include/uapi/misc/cxl.h @@ -32,10 +32,32 @@ struct cxl_ioctl_start_work { #define CXL_START_WORK_ALL (CXL_START_WORK_AMR |\ CXL_START_WORK_NUM_IRQS) + +/* Possible modes that an afu can be in */ +#define CXL_MODE_DEDICATED 0x1 +#define CXL_MODE_DIRECTED 0x2 + +/* possible flags for the cxl_afu_id flags field */ +#define CXL_AFUID_FLAG_SLAVE 0x1 /* In directed-mode afu is in slave mode */ + +struct cxl_afu_id { + __u64 flags; /* One of CXL_AFUID_FLAG_X */ + __u32 card_id; + __u32 afu_offset; + __u32 afu_mode; /* one of the CXL_MODE_X */ + __u32 reserved1; + __u64 reserved2; + __u64 reserved3; + __u64 reserved4; + __u64 reserved5; + __u64 reserved6; +}; + /* ioctl numbers */ #define CXL_MAGIC 0xCA #define CXL_IOCTL_START_WORK _IOW(CXL_MAGIC, 0x00, struct cxl_ioctl_start_work) #define CXL_IOCTL_GET_PROCESS_ELEMENT _IOR(CXL_MAGIC, 0x01, __u32) +#define CXL_IOCTL_GET_AFU_ID _IOR(CXL_MAGIC, 0x02, struct cxl_afu_id) #define CXL_READ_MIN_SIZE 0x1000 /* 4K */ -- cgit v1.2.3