An endpoint can discover the minimum size, maximum size and alignment boundary for the Rx/Tx buffers by passing the function ID of the FFA_RXTX_MAP ABI as input in the FFA_FEATURES interface. The maximum size is an optional field and a value of 0 means that the partition manager or the hypervisor does not enforce a maximum size.
Use the discovery mechanism and remove the hardcoded 4kB buffer size. If the discovery fails, it still defaults to 4kB.
Signed-off-by: Sudeep Holla sudeep.holla@arm.com --- drivers/firmware/arm_ffa/driver.c | 44 +++++++++++++++++++++++++-------------- 1 file changed, 28 insertions(+), 16 deletions(-)
diff --git a/drivers/firmware/arm_ffa/driver.c b/drivers/firmware/arm_ffa/driver.c index 90102ed7bd18..1e3764852118 100644 --- a/drivers/firmware/arm_ffa/driver.c +++ b/drivers/firmware/arm_ffa/driver.c @@ -54,11 +54,8 @@ #define PACK_TARGET_INFO(s, r) \ (FIELD_PREP(SENDER_ID_MASK, (s)) | FIELD_PREP(RECEIVER_ID_MASK, (r)))
-/* - * Keeping RX TX buffer size as 4K for now - * 64K may be preferred to keep it min a page in 64K PAGE_SIZE config - */ -#define RXTX_BUFFER_SIZE SZ_4K +#define RXTX_MAP_MIN_BUFSZ_MASK GENMASK(1, 0) +#define RXTX_MAP_MIN_BUFSZ(x) ((x) & RXTX_MAP_MIN_BUFSZ_MASK)
#define FFA_MAX_NOTIFICATIONS 64
@@ -99,6 +96,7 @@ struct ffa_drv_info { struct mutex tx_lock; /* lock to protect Tx buffer */ void *rx_buffer; void *tx_buffer; + size_t rxtx_bufsz; bool mem_ops_native; bool msg_direct_req2_supp; bool bitmap_created; @@ -454,7 +452,7 @@ static int ffa_msg_send2(u16 src_id, u16 dst_id, void *buf, size_t sz) ffa_value_t ret; int retval = 0;
- if (sz > (RXTX_BUFFER_SIZE - sizeof(*msg))) + if (sz > (drv_info->rxtx_bufsz - sizeof(*msg))) return -ERANGE;
mutex_lock(&drv_info->tx_lock); @@ -689,9 +687,10 @@ static int ffa_memory_ops(u32 func_id, struct ffa_mem_ops_args *args) { int ret; void *buffer; + size_t rxtx_bufsz = drv_info->rxtx_bufsz;
if (!args->use_txbuf) { - buffer = alloc_pages_exact(RXTX_BUFFER_SIZE, GFP_KERNEL); + buffer = alloc_pages_exact(rxtx_bufsz, GFP_KERNEL); if (!buffer) return -ENOMEM; } else { @@ -699,12 +698,12 @@ static int ffa_memory_ops(u32 func_id, struct ffa_mem_ops_args *args) mutex_lock(&drv_info->tx_lock); }
- ret = ffa_setup_and_transmit(func_id, buffer, RXTX_BUFFER_SIZE, args); + ret = ffa_setup_and_transmit(func_id, buffer, rxtx_bufsz, args);
if (args->use_txbuf) mutex_unlock(&drv_info->tx_lock); else - free_pages_exact(buffer, RXTX_BUFFER_SIZE); + free_pages_exact(buffer, rxtx_bufsz);
return ret < 0 ? ret : 0; } @@ -1718,6 +1717,8 @@ static void ffa_notifications_setup(void) static int __init ffa_init(void) { int ret; + u32 buf_sz; + size_t rxtx_bufsz = SZ_4K;
ret = ffa_transport_init(&invoke_ffa_fn); if (ret) @@ -1737,13 +1738,24 @@ static int __init ffa_init(void) goto free_drv_info; }
- drv_info->rx_buffer = alloc_pages_exact(RXTX_BUFFER_SIZE, GFP_KERNEL); + ret = ffa_features(FFA_FN_NATIVE(RXTX_MAP), 0, &buf_sz, NULL); + if (!ret) { + if (RXTX_MAP_MIN_BUFSZ(buf_sz) == 1) + rxtx_bufsz = SZ_64K; + else if (RXTX_MAP_MIN_BUFSZ(buf_sz) == 2) + rxtx_bufsz = SZ_16K; + else + rxtx_bufsz = SZ_4K; + } + + drv_info->rxtx_bufsz = rxtx_bufsz; + drv_info->rx_buffer = alloc_pages_exact(rxtx_bufsz, GFP_KERNEL); if (!drv_info->rx_buffer) { ret = -ENOMEM; goto free_pages; }
- drv_info->tx_buffer = alloc_pages_exact(RXTX_BUFFER_SIZE, GFP_KERNEL); + drv_info->tx_buffer = alloc_pages_exact(rxtx_bufsz, GFP_KERNEL); if (!drv_info->tx_buffer) { ret = -ENOMEM; goto free_pages; @@ -1751,7 +1763,7 @@ static int __init ffa_init(void)
ret = ffa_rxtx_map(virt_to_phys(drv_info->tx_buffer), virt_to_phys(drv_info->rx_buffer), - RXTX_BUFFER_SIZE / FFA_PAGE_SIZE); + rxtx_bufsz / FFA_PAGE_SIZE); if (ret) { pr_err("failed to register FFA RxTx buffers\n"); goto free_pages; @@ -1781,8 +1793,8 @@ static int __init ffa_init(void) ffa_notifications_cleanup(); free_pages: if (drv_info->tx_buffer) - free_pages_exact(drv_info->tx_buffer, RXTX_BUFFER_SIZE); - free_pages_exact(drv_info->rx_buffer, RXTX_BUFFER_SIZE); + free_pages_exact(drv_info->tx_buffer, rxtx_bufsz); + free_pages_exact(drv_info->rx_buffer, rxtx_bufsz); free_drv_info: kfree(drv_info); return ret; @@ -1794,8 +1806,8 @@ static void __exit ffa_exit(void) ffa_notifications_cleanup(); ffa_partitions_cleanup(); ffa_rxtx_unmap(drv_info->vm_id); - free_pages_exact(drv_info->tx_buffer, RXTX_BUFFER_SIZE); - free_pages_exact(drv_info->rx_buffer, RXTX_BUFFER_SIZE); + 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); } module_exit(ffa_exit);