[PATCH v2 1/3] powerpc/microwatt: wire up rng during setup_arch

Jason A. Donenfeld Jason at zx2c4.com
Sat Jun 11 20:04:45 AEST 2022


The platform's RNG must be available before random_init() in order to be
useful for initial seeding, which in turn means that it needs to be
called from setup_arch(), rather than from an init call. Fortunately,
each platform already has a setup_arch function pointer, which means
it's easy to wire this up for each of the three platforms that have an
RNG. This commit also removes some noisy log messages that don't add
much.

Cc: stable at vger.kernel.org
Cc: Michael Ellerman <mpe at ellerman.id.au>
Cc: Christophe Leroy <christophe.leroy at csgroup.eu>
Fixes: c25769fddaec ("powerpc/microwatt: Add support for hardware random number generator")
Signed-off-by: Jason A. Donenfeld <Jason at zx2c4.com>
---
 arch/powerpc/platforms/microwatt/rng.c   | 9 ++-------
 arch/powerpc/platforms/microwatt/setup.c | 8 ++++++++
 2 files changed, 10 insertions(+), 7 deletions(-)

diff --git a/arch/powerpc/platforms/microwatt/rng.c b/arch/powerpc/platforms/microwatt/rng.c
index 7bc4d1cbfaf0..d13f656910ad 100644
--- a/arch/powerpc/platforms/microwatt/rng.c
+++ b/arch/powerpc/platforms/microwatt/rng.c
@@ -29,7 +29,7 @@ static int microwatt_get_random_darn(unsigned long *v)
 	return 1;
 }
 
-static __init int rng_init(void)
+__init void microwatt_rng_init(void)
 {
 	unsigned long val;
 	int i;
@@ -37,12 +37,7 @@ static __init int rng_init(void)
 	for (i = 0; i < 10; i++) {
 		if (microwatt_get_random_darn(&val)) {
 			ppc_md.get_random_seed = microwatt_get_random_darn;
-			return 0;
+			return;
 		}
 	}
-
-	pr_warn("Unable to use DARN for get_random_seed()\n");
-
-	return -EIO;
 }
-machine_subsys_initcall(, rng_init);
diff --git a/arch/powerpc/platforms/microwatt/setup.c b/arch/powerpc/platforms/microwatt/setup.c
index 0b02603bdb74..23c996dcc870 100644
--- a/arch/powerpc/platforms/microwatt/setup.c
+++ b/arch/powerpc/platforms/microwatt/setup.c
@@ -32,10 +32,18 @@ static int __init microwatt_populate(void)
 }
 machine_arch_initcall(microwatt, microwatt_populate);
 
+__init void microwatt_rng_init(void);
+
+static void __init microwatt_setup_arch(void)
+{
+	microwatt_rng_init();
+}
+
 define_machine(microwatt) {
 	.name			= "microwatt",
 	.probe			= microwatt_probe,
 	.init_IRQ		= microwatt_init_IRQ,
+	.setup_arch		= microwatt_setup_arch,
 	.progress		= udbg_progress,
 	.calibrate_decr		= generic_calibrate_decr,
 };
-- 
2.35.1



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