[PATCH 5/9] firmware: arm_ffa: Use FFA_FEATURES to detect if native versions are supported

Sudeep Holla
2022-08-30T10:12:28Z

Currently, the ffa_dev->mode_32bit is use to detect if the native 64-bit
or 32-bit versions of FF-A ABI needs to be used. However for the FF-A
memory ABIs, it is not dependent on the ffa_device(i.e. the partition)
itself, but the partition manager(SPM).

So, the FFA_FEATURES can be use to detect if the native 64bit ABIs are
supported or not and appropriate calls can be made based on that.

Use FFA_FEATURES to detect if native versions of MEM_LEND or MEM_SHARE
are implemented and make of the same to use native memory ABIs later on.

Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
---
drivers/firmware/arm_ffa/driver.c | 22 ++++++++++++++++------
1 file changed, 16 insertions(+), 6 deletions(-)

diff --git a/drivers/firmware/arm_ffa/driver.c b/drivers/firmware/arm_ffa/driver.c
index de94073f4109..5f02b670e964 100644
--- a/drivers/firmware/arm_ffa/driver.c
+++ b/drivers/firmware/arm_ffa/driver.c
@@ -163,6 +163,7 @@ struct ffa_drv_info {
struct mutex tx_lock; /* lock to protect Tx buffer */
void *rx_buffer;
void *tx_buffer;
+ bool mem_ops_native;
};

static struct ffa_drv_info *drv_info;
@@ -594,6 +595,13 @@ static int ffa_features(u32 func_feat_id, u32 input_props, u32 *if_props)
return 0;
}

+static void ffa_set_up_mem_ops_native_flag(void)
+{
+ if (!ffa_features(FFA_FN_NATIVE(MEM_LEND), 0, NULL) ||
+ !ffa_features(FFA_FN_NATIVE(MEM_SHARE), 0, NULL))
+ drv_info->mem_ops_native = true;
+}
+
static u32 ffa_api_version_get(void)
{
return drv_info->version;
@@ -635,10 +643,10 @@ static int ffa_sync_send_receive(struct ffa_device *dev,
static int
ffa_memory_share(struct ffa_device *dev, struct ffa_mem_ops_args *args)
{
- if (dev->mode_32bit)
- return ffa_memory_ops(FFA_MEM_SHARE, args);
+ if (drv_info->mem_ops_native)
+ return ffa_memory_ops(FFA_FN_NATIVE(MEM_SHARE), args);

- return ffa_memory_ops(FFA_FN_NATIVE(MEM_SHARE), args);
+ return ffa_memory_ops(FFA_MEM_SHARE, args);
}

static int
@@ -651,10 +659,10 @@ ffa_memory_lend(struct ffa_device *dev, struct ffa_mem_ops_args *args)
* however on systems without a hypervisor the responsibility
* falls to the calling kernel driver to prevent access.
*/
- if (dev->mode_32bit)
- return ffa_memory_ops(FFA_MEM_LEND, args);
+ if (drv_info->mem_ops_native)
+ return ffa_memory_ops(FFA_FN_NATIVE(MEM_LEND), args);

- return ffa_memory_ops(FFA_FN_NATIVE(MEM_LEND), args);
+ return ffa_memory_ops(FFA_MEM_LEND, args);
}

static const struct ffa_dev_ops ffa_ops = {
@@ -765,6 +773,8 @@ static int __init ffa_init(void)

ffa_setup_partitions();

+ ffa_set_up_mem_ops_native_flag();
+
return 0;
free_pages:
if (drv_info->tx_buffer)
--
2.37.2