[PATCH 2/2] arm: mach-snapdrgon: misc: Simplify msm_generate_mac_addr()

Stephan Gerhold stephan at gerhold.net
Mon Aug 2 16:52:31 CEST 2021


The logic in msm_generate_mac_addr() was originally taken from the LK
bootloader where the serial number is a string and must be parsed first.
However, in U-Boot msm_board_serial() returns an u32 and
msm_generate_mac_addr() has quite complicated code that will first
print it as a hex string and then immediately parse it again.

What this function actually does at the end is to put the serial number
encoded as big endian (the order used for the hex string) into the u8 *mac.
Use put_unaligned_be32() to do that with bit shifts instead of going
through the string format.

This should be slightly more efficient and cleaner but does not result
in any functional difference.

Cc: Ramon Fried <rfried.dev at gmail.com>
Signed-off-by: Stephan Gerhold <stephan at gerhold.net>
---

 arch/arm/mach-snapdragon/misc.c | 13 +++----------
 1 file changed, 3 insertions(+), 10 deletions(-)

diff --git a/arch/arm/mach-snapdragon/misc.c b/arch/arm/mach-snapdragon/misc.c
index 5c062e9636..02edfda5d6 100644
--- a/arch/arm/mach-snapdragon/misc.c
+++ b/arch/arm/mach-snapdragon/misc.c
@@ -9,6 +9,7 @@
 #include <common.h>
 #include <mmc.h>
 #include <asm/arch/misc.h>
+#include <asm/unaligned.h>
 
 /* UNSTUFF_BITS macro taken from Linux Kernel: drivers/mmc/core/sd.c */
 #define UNSTUFF_BITS(resp, start, size) \
@@ -41,16 +42,8 @@ u32 msm_board_serial(void)
 
 void msm_generate_mac_addr(u8 *mac)
 {
-	int i;
-	char sn[9];
-
-	snprintf(sn, 9, "%08x", msm_board_serial());
-
 	/* fill in the mac with serialno, use locally adminstrated pool */
 	mac[0] = 0x02;
-	mac[1] = 00;
-	for (i = 3; i >= 0; i--) {
-		mac[i + 2] = simple_strtoul(&sn[2 * i], NULL, 16);
-		sn[2 * i] = 0;
-	}
+	mac[1] = 0x00;
+	put_unaligned_be32(msm_board_serial(), &mac[2]);
 }
-- 
2.32.0



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