On 5/12/22 01:18, Serge Semin wrote:
Currently there are four port-map-related fields declared in the ahci_host_priv structure and used to setup the HBA ports mapping. First the ports-mapping is read from the PI register and immediately stored in the saved_port_map field. If forced_port_map is initialized with non-zero value then its value will have greater priority over the value read from PI, thus it will override the saved_port_map field. That value will be then masked by a non-zero mask_port_map field and after some sanity checks it will be stored in the ahci_host_priv.port_map field as a final port mapping. As you can see the logic is a bit too complicated for such a simple task. We can freely get rid from at least one of the fields with no change to the implemented semantic. The force_port_map field can be replaced with taking non-zero saved_port_map value into account. So if saved_port_map is pre-initialized by the low level drivers (platform drivers) then it will have greater priority over the value read from PI register and will be used as actual HBA ports mapping later on. Thus the ports map forcing task will be just transferred from the force_port_map to saved_port_map field. This modification will perfectly fit into the feature of having OF-based initialization of the HW-init HBA CSR fields we are about to introduce in the next commit. Signed-off-by: Serge Semin <Sergey.Semin@xxxxxxxxxxxxxxxxxxxx> --- drivers/ata/ahci.c | 2 +- drivers/ata/ahci.h | 1 - drivers/ata/libahci.c | 10 ++++++---- drivers/ata/libahci_platform.c | 2 +- 4 files changed, 8 insertions(+), 7 deletions(-)
Reviewed-by: Hannes Reinecke <hare@xxxxxxx> Cheers, Hannes -- Dr. Hannes Reinecke Kernel Storage Architect hare@xxxxxxx +49 911 74053 688 SUSE Software Solutions Germany GmbH, Maxfeldstr. 5, 90409 Nürnberg HRB 36809 (AG Nürnberg), GF: Felix Imendörffer