linux-kernel - [tip: timers/core] clocksource/drivers/renesas-ostm: Avoid reprobe after successful early probe

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Date: Fri, 10 May 2024 11:10:55 -0000
From: "tip-bot2 for Geert Uytterhoeven" <tip-bot2@...utronix.de>
To: linux-tip-commits@...r.kernel.org
Cc: Geert Uytterhoeven <geert+renesas@...der.be>,
 Daniel Lezcano <daniel.lezcano@...aro.org>, x86@...nel.org,
 linux-kernel@...r.kernel.org
Subject: [tip: timers/core] clocksource/drivers/renesas-ostm: Avoid reprobe
 after successful early probe

The following commit has been merged into the timers/core branch of tip:

Commit-ID:     37385c0772a4fc6b89605b9701fa934fa2beb2cc
Gitweb:        https://git.kernel.org/tip/37385c0772a4fc6b89605b9701fa934fa2beb2cc
Author:        Geert Uytterhoeven <geert+renesas@...der.be>
AuthorDate:    Wed, 20 Mar 2024 11:30:07 +01:00
Committer:     Daniel Lezcano <daniel.lezcano@...aro.org>
CommitterDate: Fri, 10 May 2024 10:41:52 +02:00

clocksource/drivers/renesas-ostm: Avoid reprobe after successful early probe

The Renesas OS Timer (OSTM) driver contains two probe points, of which
only one should complete:
  1. Early probe, using TIMER_OF_DECLARE(), to provide the sole
     clocksource on (arm32) RZ/A1 and RZ/A2 SoCs,
  2. Normal probe, using a platform driver, to provide additional timers
     on (arm64 + riscv) RZ/G2L and similar SoCs.

The latter is needed because using OSTM on RZ/G2L requires manipulation
of its reset signal, which is not yet available at the time of early
probe, causing early probe to fail with -EPROBE_DEFER.  It is only
enabled when building a kernel with support for the RZ/G2L family, so it
does not impact RZ/A1 and RZ/A2.  Hence only one probe method can
complete on all affected systems.

As relying on the order of initialization of subsystems inside the
kernel is fragile, set the DT node's OF_POPULATED flag after a succesful
early probe.  This makes sure the platform driver's probe is never
called after a successful early probe.

Signed-off-by: Geert Uytterhoeven <geert+renesas@...der.be>
Reviwed-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@...renesas.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@...aro.org>
Link: https://lore.kernel.org/r/bd027379713cbaafa21ffe9e848ebb7f475ca0e7.1710930542.git.geert+renesas@glider.be
---
 drivers/clocksource/renesas-ostm.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/clocksource/renesas-ostm.c b/drivers/clocksource/renesas-ostm.c
index 39487d0..3fcbd02 100644
--- a/drivers/clocksource/renesas-ostm.c
+++ b/drivers/clocksource/renesas-ostm.c
@@ -210,6 +210,7 @@ static int __init ostm_init(struct device_node *np)
 		pr_info("%pOF: used for clock events\n", np);
 	}
 
+	of_node_set_flag(np, OF_POPULATED);
 	return 0;
 
 err_cleanup: