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authorGravatar Sudeep Holla <sudeep.holla@arm.com> 2023-05-03 14:12:52 +0100
committerGravatar Sudeep Holla <sudeep.holla@arm.com> 2023-05-08 20:40:46 +0100
commit111a833dc5cbef3d05b2a796a7e23cb7f6ff2192 (patch)
tree6acc96f8f5e34b7e97f74848ac3bfe793371dd1e /drivers/firmware
parentfirmware: arm_ffa: Fix FFA device names for logical partitions (diff)
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firmware: arm_ffa: Set reserved/MBZ fields to zero in the memory descriptors
The transmit buffers allocated by the driver can be used to transmit data by any messages/commands needing the buffer. However, it is not guaranteed to have been zero-ed before every new transmission and hence it will just contain residual value from the previous transmission. There are several reserved fields in the memory descriptors that must be zero(MBZ). The receiver can reject the transmission if any such MBZ fields are non-zero. While we can set the whole page to zero, it is not optimal as most of the fields get initialised to the value required for the current transmission. So, just set the reserved/MBZ fields to zero in the memory descriptors explicitly to honour the requirement and keep the receiver happy. Fixes: cc2195fe536c ("firmware: arm_ffa: Add support for MEM_* interfaces") Reported-by: Marc Bonnici <marc.bonnici@arm.com> Link: https://lore.kernel.org/r/20230503131252.12585-1-sudeep.holla@arm.com Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Diffstat (limited to 'drivers/firmware')
-rw-r--r--drivers/firmware/arm_ffa/driver.c6
1 files changed, 6 insertions, 0 deletions
diff --git a/drivers/firmware/arm_ffa/driver.c b/drivers/firmware/arm_ffa/driver.c
index 4aced2e5b772..e23409138667 100644
--- a/drivers/firmware/arm_ffa/driver.c
+++ b/drivers/firmware/arm_ffa/driver.c
@@ -421,12 +421,17 @@ ffa_setup_and_transmit(u32 func_id, void *buffer, u32 max_fragsize,
ep_mem_access->receiver = args->attrs[idx].receiver;
ep_mem_access->attrs = args->attrs[idx].attrs;
ep_mem_access->composite_off = COMPOSITE_OFFSET(args->nattrs);
+ ep_mem_access->flag = 0;
+ ep_mem_access->reserved = 0;
}
+ mem_region->reserved_0 = 0;
+ mem_region->reserved_1 = 0;
mem_region->ep_count = args->nattrs;
composite = buffer + COMPOSITE_OFFSET(args->nattrs);
composite->total_pg_cnt = ffa_get_num_pages_sg(args->sg);
composite->addr_range_cnt = num_entries;
+ composite->reserved = 0;
length = COMPOSITE_CONSTITUENTS_OFFSET(args->nattrs, num_entries);
frag_len = COMPOSITE_CONSTITUENTS_OFFSET(args->nattrs, 0);
@@ -461,6 +466,7 @@ ffa_setup_and_transmit(u32 func_id, void *buffer, u32 max_fragsize,
constituents->address = sg_phys(args->sg);
constituents->pg_cnt = args->sg->length / FFA_PAGE_SIZE;
+ constituents->reserved = 0;
constituents++;
frag_len += sizeof(struct ffa_mem_region_addr_range);
} while ((args->sg = sg_next(args->sg)));