cdx: add the cdx bus driver

Introduce AMD CDX bus, which provides a mechanism for scanning
and probing CDX devices. These devices are memory mapped on
system bus for Application Processors(APUs).

CDX devices can be changed dynamically in the Fabric and CDX
bus interacts with CDX controller to rescan the bus and
rediscover the devices.

Signed-off-by: Nipun Gupta <[email protected]>
Reviewed-by: Pieter Jansen van Vuuren <[email protected]>
Tested-by: Nikhil Agarwal <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

1 files changed, 12 insertions, 0 deletions

diff --git a/scripts/mod/file2alias.c b/scripts/mod/file2alias.c
index 91c2e7ba5e52..28da34ba4359 100644
--- a/scripts/mod/file2alias.c
+++ b/scripts/mod/file2alias.c
@@ -1452,6 +1452,17 @@ static int do_dfl_entry(const char *filename, void *symval, char *alias)
 	return 1;
 }
 
+/* Looks like: cdx:vNdN */
+static int do_cdx_entry(const char *filename, void *symval,
+			char *alias)
+{
+	DEF_FIELD(symval, cdx_device_id, vendor);
+	DEF_FIELD(symval, cdx_device_id, device);
+
+	sprintf(alias, "cdx:v%08Xd%08Xd", vendor, device);
+	return 1;
+}
+
 /* Does namelen bytes of name exactly match the symbol? */
 static bool sym_is(const char *name, unsigned namelen, const char *symbol)
 {
@@ -1531,6 +1542,7 @@ static const struct devtable devtable[] = {
 	{"ssam", SIZE_ssam_device_id, do_ssam_entry},
 	{"dfl", SIZE_dfl_device_id, do_dfl_entry},
 	{"ishtp", SIZE_ishtp_device_id, do_ishtp_entry},
+	{"cdx", SIZE_cdx_device_id, do_cdx_entry},
 };
 
 /* Create MODULE_ALIAS() statements.