@@ -1438,6 +1438,51 @@ static int get_device_uid(struct device *d){
}
static off_t get_rcrb_base(int device_uid){
+ FILE *cedt_file = fopen("/sys/firmware/acpi/tables/CEDT", "rb");
+ if (cedt_file == NULL)
+ return -1;
+
+ struct CEDT_Header header;
+ fread(&header, sizeof(header), 1, cedt_file);
+
+ struct CHBS_Structure chbs;
+ chbs.base = 0;
+ size_t total_bytes_read = 0;
+ while (total_bytes_read < header.length)
+ {
+ struct CEDT_Structure cedt;
+ size_t bytes_read = fread(&cedt, sizeof(cedt), 1, cedt_file);
+ if (bytes_read != 1)
+ {
+ fclose(cedt_file);
+ return -1;
+ }
+ total_bytes_read += sizeof(cedt);
+ if (cedt.type == CHBS_TYPE)
+ {
+ bytes_read = fread(&chbs, sizeof(chbs), 1, cedt_file);
+ if(bytes_read != 1){
+ fclose(cedt_file);
+ return -1;
+ }
+ total_bytes_read += sizeof(chbs);
+ if ((int)chbs.uid == device_uid){
+ if(chbs.cxl_version == 0){
+ fclose(cedt_file);
+ return chbs.base;
+ }else{
+ fclose(cedt_file);
+ return -1;
+ }
+ }
+ }
+ else
+ {
+ fseek(cedt_file, cedt.record_length - sizeof(cedt), SEEK_SET);
+ total_bytes_read += cedt.record_length;
+ }
+ }
+ fclose(cedt_file);
return -1;
}
This patch adds a function to obtain the RCRB base address corresponding to the uid. In the case of a CXL1.1 device, the RCRB base address is included in the CHBS in the CEDT (cxl3.0 specification 9.17.1). In this function, the ACPI's CEDT is explored, and the RCRB base address is obtained from the CHBS corresponding to the uid. Signed-off-by: KobayashiDaisuke <kobayashi.da-06@fujitsu.com> --- ls-caps.c | 45 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 45 insertions(+)