diff options
| author | Yeoreum Yun <yeoreum.yun@arm.com> | 2026-03-04 12:09:53 +0000 |
|---|---|---|
| committer | Sudeep Holla <sudeep.holla@kernel.org> | 2026-03-06 16:26:08 +0000 |
| commit | a4e8473b775160f3ce978f621cf8dea2c7250433 (patch) | |
| tree | e1cff49fa621068595bd9be772b45722a0e28772 /drivers | |
| parent | 6de23f81a5e08be8fbf5e8d7e9febc72a5b5f27f (diff) | |
firmware: arm_ffa: Remove vm_id argument in ffa_rxtx_unmap()
According to the FF-A specification (DEN0077, v1.1, ยง13.7), when
FFA_RXTX_UNMAP is invoked from any instance other than non-secure
physical, the w1 register must be zero (MBZ). If a non-zero value is
supplied in this context, the SPMC must return FFA_INVALID_PARAMETER.
The Arm FF-A driver operates exclusively as a guest or non-secure
physical instance where the partition ID is always zero and is not
invoked from a hypervisor context where w1 carries a VM ID. In this
execution model, the partition ID observed by the driver is always zero,
and passing a VM ID is unnecessary and potentially invalid.
Remove the vm_id parameter from ffa_rxtx_unmap() and ensure that the
SMC call is issued with w1 implicitly zeroed, as required by the
specification. This prevents invalid parameter errors and aligns the
implementation with the defined FF-A ABI behavior.
Fixes: 3bbfe9871005 ("firmware: arm_ffa: Add initial Arm FFA driver support")
Signed-off-by: Yeoreum Yun <yeoreum.yun@arm.com>
Message-Id: <20260304120953.847671-1-yeoreum.yun@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@kernel.org>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/firmware/arm_ffa/driver.c | 8 |
1 files changed, 4 insertions, 4 deletions
diff --git a/drivers/firmware/arm_ffa/driver.c b/drivers/firmware/arm_ffa/driver.c index 12a625387d6e..f2f94d4d533e 100644 --- a/drivers/firmware/arm_ffa/driver.c +++ b/drivers/firmware/arm_ffa/driver.c @@ -205,12 +205,12 @@ static int ffa_rxtx_map(phys_addr_t tx_buf, phys_addr_t rx_buf, u32 pg_cnt) return 0; } -static int ffa_rxtx_unmap(u16 vm_id) +static int ffa_rxtx_unmap(void) { ffa_value_t ret; invoke_ffa_fn((ffa_value_t){ - .a0 = FFA_RXTX_UNMAP, .a1 = PACK_TARGET_INFO(vm_id, 0), + .a0 = FFA_RXTX_UNMAP, }, &ret); if (ret.a0 == FFA_ERROR) @@ -2097,7 +2097,7 @@ static int __init ffa_init(void) pr_err("failed to setup partitions\n"); ffa_notifications_cleanup(); - ffa_rxtx_unmap(drv_info->vm_id); + ffa_rxtx_unmap(); free_pages: if (drv_info->tx_buffer) free_pages_exact(drv_info->tx_buffer, rxtx_bufsz); @@ -2112,7 +2112,7 @@ static void __exit ffa_exit(void) { ffa_notifications_cleanup(); ffa_partitions_cleanup(); - ffa_rxtx_unmap(drv_info->vm_id); + ffa_rxtx_unmap(); free_pages_exact(drv_info->tx_buffer, drv_info->rxtx_bufsz); free_pages_exact(drv_info->rx_buffer, drv_info->rxtx_bufsz); kfree(drv_info); |