Thread (16 messages) 16 messages, 6 authors, 2024-03-08
STALE855d LANDED: 1 (1M)
Revisions (4)
  1. v1 [diff vs current]
  2. v2 [diff vs current]
  3. v3 [diff vs current]
  4. v4 current

[PATCH v4 4/7] x86/of: Unconditionally call unflatten_and_copy_device_tree()

From: Stephen Boyd <sboyd@kernel.org>
Date: 2024-02-17 01:06:01
Also in: linux-devicetree, linux-kselftest, linux-patches, linux-um, lkml
Subsystem: the rest, x86 architecture (32-bit and 64-bit) · Maintainers: Linus Torvalds, Thomas Gleixner, Ingo Molnar, Borislav Petkov, Dave Hansen

Call this function unconditionally so that we can populate an empty DTB
on platforms that don't boot with a firmware provided or builtin DTB.
There's no harm in calling unflatten_device_tree() unconditionally here.
If there isn't a non-NULL 'initial_boot_params' pointer then
unflatten_device_tree() returns early.

Cc: Rob Herring <robh+dt@kernel.org>
Cc: Frank Rowand <redacted>
Cc: Thomas Gleixner <redacted>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: <x86@kernel.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Tested-by: Saurabh Sengar <ssengar@linux.microsoft.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
---
 arch/x86/kernel/devicetree.c | 24 +++++++++++++-----------
 1 file changed, 13 insertions(+), 11 deletions(-)
diff --git a/arch/x86/kernel/devicetree.c b/arch/x86/kernel/devicetree.c
index afd09924094e..650752d112a6 100644
--- a/arch/x86/kernel/devicetree.c
+++ b/arch/x86/kernel/devicetree.c
@@ -283,22 +283,24 @@ void __init x86_flattree_get_config(void)
 	u32 size, map_len;
 	void *dt;
 
-	if (!initial_dtb)
-		return;
+	if (initial_dtb) {
+		map_len = max(PAGE_SIZE - (initial_dtb & ~PAGE_MASK), (u64)128);
 
-	map_len = max(PAGE_SIZE - (initial_dtb & ~PAGE_MASK), (u64)128);
+		dt = early_memremap(initial_dtb, map_len);
+		size = fdt_totalsize(dt);
+		if (map_len < size) {
+			early_memunmap(dt, map_len);
+			dt = early_memremap(initial_dtb, size);
+			map_len = size;
+		}
 
-	dt = early_memremap(initial_dtb, map_len);
-	size = fdt_totalsize(dt);
-	if (map_len < size) {
-		early_memunmap(dt, map_len);
-		dt = early_memremap(initial_dtb, size);
-		map_len = size;
+		early_init_dt_verify(dt);
 	}
 
-	early_init_dt_verify(dt);
 	unflatten_and_copy_device_tree();
-	early_memunmap(dt, map_len);
+
+	if (initial_dtb)
+		early_memunmap(dt, map_len);
 }
 #endif
 
-- 
https://git.kernel.org/pub/scm/linux/kernel/git/clk/linux.git/
https://git.kernel.org/pub/scm/linux/kernel/git/sboyd/spmi.git


_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
Keyboard shortcuts
hback out one level
jnext message in thread
kprevious message in thread
ldrill in
Escclose help / fold thread tree
?toggle this help