[PATCH 08/13] Xen: EFI: Parse DT parameters for Xen specific UEFI

[shannon.zhao-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org]

From: Shannon Zhao <shannon.zhao-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>

Add a new function to parse DT parameters for Xen specific UEFI just
like the way for normal UEFI. Then it could reuse the existing codes.

Signed-off-by: Shannon Zhao <shannon.zhao-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>
---
 drivers/firmware/efi/efi.c | 67 ++++++++++++++++++++++++++++++++++++++++++----
 1 file changed, 62 insertions(+), 5 deletions(-)

diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c
index d6144e3..629bd06 100644
--- a/drivers/firmware/efi/efi.c
+++ b/drivers/firmware/efi/efi.c
@@ -24,6 +24,7 @@
 #include <linux/of_fdt.h>
 #include <linux/io.h>
 #include <linux/platform_device.h>
+#include <xen/xen.h>
 
 struct efi __read_mostly efi = {
 	.mps        = EFI_INVALID_TABLE_ADDR,
@@ -488,12 +489,60 @@ static __initdata struct {
 	UEFI_PARAM("MemMap Desc. Version", "linux,uefi-mmap-desc-ver", desc_ver)
 };
 
+static __initdata struct {
+	const char name[32];
+	const char propname[32];
+	int offset;
+	int size;
+} xen_dt_params[] = {
+	UEFI_PARAM("System Table", "xen,uefi-system-table", system_table),
+	UEFI_PARAM("MemMap Address", "xen,uefi-mmap-start", mmap),
+	UEFI_PARAM("MemMap Size", "xen,uefi-mmap-size", mmap_size),
+	UEFI_PARAM("MemMap Desc. Size", "xen,uefi-mmap-desc-size", desc_size),
+	UEFI_PARAM("MemMap Desc. Version", "xen,uefi-mmap-desc-ver", desc_ver)
+};
+
 struct param_info {
 	int verbose;
 	int found;
 	void *params;
 };
 
+static int __init fdt_find_xen_uefi_params(unsigned long node,
+					   const char *uname, int depth,
+					   void *data)
+{
+	struct param_info *info = data;
+	const void *prop;
+	void *dest;
+	u64 val;
+	int i, len;
+
+	if (xen_initial_domain() && (depth != 2 || strcmp(uname, "uefi") != 0))
+		return 0;
+
+	for (i = 0; i < ARRAY_SIZE(xen_dt_params); i++) {
+		prop = of_get_flat_dt_prop(node, xen_dt_params[i].propname,
+					   &len);
+		if (!prop)
+			return 0;
+		dest = info->params + xen_dt_params[i].offset;
+		info->found++;
+
+		val = of_read_number(prop, len / sizeof(u32));
+
+		if (dt_params[i].size == sizeof(u32))
+			*(u32 *)dest = val;
+		else
+			*(u64 *)dest = val;
+
+		if (info->verbose)
+			pr_info("  %s: 0x%0*llx\n", xen_dt_params[i].name,
+				xen_dt_params[i].size * 2, val);
+	}
+
+	return 1;
+}
 static int __init fdt_find_uefi_params(unsigned long node, const char *uname,
 				       int depth, void *data)
 {
@@ -538,12 +587,20 @@ int __init efi_get_fdt_params(struct efi_fdt_params *params, int verbose)
 	info.found = 0;
 	info.params = params;
 
-	ret = of_scan_flat_dt(fdt_find_uefi_params, &info);
-	if (!info.found)
+	if (xen_initial_domain())
+		ret = of_scan_flat_dt(fdt_find_xen_uefi_params, &info);
+	else
+		ret = of_scan_flat_dt(fdt_find_uefi_params, &info);
+	if (!info.found) {
 		pr_info("UEFI not found.\n");
-	else if (!ret)
-		pr_err("Can't find '%s' in device tree!\n",
-		       dt_params[info.found].name);
+	} else if (!ret) {
+		if (xen_initial_domain())
+			pr_err("Can't find '%s' in device tree!\n",
+			       xen_dt_params[info.found].name);
+		else
+			pr_err("Can't find '%s' in device tree!\n",
+			       xen_dt_params[info.found].name);
+	}
 
 	return ret;
 }
-- 
2.1.0