[PATCH v3 3/3] powerpc/pseries: wire up rng during setup_arch

From: Jason A. Donenfeld
Date: Sat Jun 11 2022 - 11:10:48 EST


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. This commit also removes some noisy log
messages that don't add much.

Cc: stable@xxxxxxxxxxxxxxx
Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Cc: Christophe Leroy <christophe.leroy@xxxxxxxxxx>
Fixes: a489043f4626 ("powerpc/pseries: Implement arch_get_random_long() based on H_RANDOM")
Signed-off-by: Jason A. Donenfeld <Jason@xxxxxxxxx>
---
arch/powerpc/platforms/pseries/pseries.h | 2 ++
arch/powerpc/platforms/pseries/rng.c | 11 +++--------
arch/powerpc/platforms/pseries/setup.c | 1 +
3 files changed, 6 insertions(+), 8 deletions(-)

diff --git a/arch/powerpc/platforms/pseries/pseries.h b/arch/powerpc/platforms/pseries/pseries.h
index f5c916c839c9..1d75b7742ef0 100644
--- a/arch/powerpc/platforms/pseries/pseries.h
+++ b/arch/powerpc/platforms/pseries/pseries.h
@@ -122,4 +122,6 @@ void pseries_lpar_read_hblkrm_characteristics(void);
static inline void pseries_lpar_read_hblkrm_characteristics(void) { }
#endif

+void pseries_rng_init(void);
+
#endif /* _PSERIES_PSERIES_H */
diff --git a/arch/powerpc/platforms/pseries/rng.c b/arch/powerpc/platforms/pseries/rng.c
index 6268545947b8..6ddfdeaace9e 100644
--- a/arch/powerpc/platforms/pseries/rng.c
+++ b/arch/powerpc/platforms/pseries/rng.c
@@ -10,6 +10,7 @@
#include <asm/archrandom.h>
#include <asm/machdep.h>
#include <asm/plpar_wrappers.h>
+#include "pseries.h"


static int pseries_get_random_long(unsigned long *v)
@@ -24,19 +25,13 @@ static int pseries_get_random_long(unsigned long *v)
return 0;
}

-static __init int rng_init(void)
+void __init pseries_rng_init(void)
{
struct device_node *dn;

dn = of_find_compatible_node(NULL, NULL, "ibm,random");
if (!dn)
- return -ENODEV;
-
- pr_info("Registering arch random hook.\n");
-
+ return;
ppc_md.get_random_seed = pseries_get_random_long;
-
of_node_put(dn);
- return 0;
}
-machine_subsys_initcall(pseries, rng_init);
diff --git a/arch/powerpc/platforms/pseries/setup.c b/arch/powerpc/platforms/pseries/setup.c
index afb074269b42..ee4f1db49515 100644
--- a/arch/powerpc/platforms/pseries/setup.c
+++ b/arch/powerpc/platforms/pseries/setup.c
@@ -839,6 +839,7 @@ static void __init pSeries_setup_arch(void)
}

ppc_md.pcibios_root_bridge_prepare = pseries_root_bridge_prepare;
+ pseries_rng_init();
}

static void pseries_panic(char *str)
--
2.35.1