[PATCH v2] soc: mediatek: mtk-svs: Enable the IRQ later

From: Ricardo Ribalda <ribalda@chromium.org>
To: Matthias Brugger <matthias.bgg@gmail.com>,
	Roger Lu <Roger.Lu@mediatek.com>
Cc: linux-arm-kernel@lists.infradead.org,
	linux-mediatek@lists.infradead.org,
	Ricardo Ribalda <ribalda@chromium.org>,
	linux-kernel@vger.kernel.org
Subject: [PATCH v2] soc: mediatek: mtk-svs: Enable the IRQ later
Date: Tue, 20 Dec 2022 22:35:59 +0100	[thread overview]
Message-ID: <20221127-mtk-svs-v2-0-145b07663ea8@chromium.org> (raw)

If the system does not come from reset (like when is booted via
kexec()), the peripheral might triger an IRQ before the data structures
are initialised.

Fixes:

[    0.227710] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000f08
[    0.227913] Call trace:
[    0.227918]  svs_isr+0x8c/0x538

Signed-off-by: Ricardo Ribalda <ribalda@chromium.org>
---
To: Matthias Brugger <matthias.bgg@gmail.com>
To: Roger Lu <Roger.Lu@mediatek.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-mediatek@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
---
Changes in v2:
- Enable the irq before svs_start, to avoid MT8192 not starting.
- Link to v1: https://lore.kernel.org/r/20221127-mtk-svs-v1-0-7a5819595838@chromium.org
---
 drivers/soc/mediatek/mtk-svs.c | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/drivers/soc/mediatek/mtk-svs.c b/drivers/soc/mediatek/mtk-svs.c
index 0469c9dfeb04..75b2f534aa9d 100644
--- a/drivers/soc/mediatek/mtk-svs.c
+++ b/drivers/soc/mediatek/mtk-svs.c
@@ -2385,14 +2385,6 @@ static int svs_probe(struct platform_device *pdev)
 		goto svs_probe_free_resource;
 	}
 
-	ret = devm_request_threaded_irq(svsp->dev, svsp_irq, NULL, svs_isr,
-					IRQF_ONESHOT, svsp->name, svsp);
-	if (ret) {
-		dev_err(svsp->dev, "register irq(%d) failed: %d\n",
-			svsp_irq, ret);
-		goto svs_probe_free_resource;
-	}
-
 	svsp->main_clk = devm_clk_get(svsp->dev, "main");
 	if (IS_ERR(svsp->main_clk)) {
 		dev_err(svsp->dev, "failed to get clock: %ld\n",
@@ -2414,6 +2406,14 @@ static int svs_probe(struct platform_device *pdev)
 		goto svs_probe_clk_disable;
 	}
 
+	ret = devm_request_threaded_irq(svsp->dev, svsp_irq, NULL, svs_isr,
+					IRQF_ONESHOT, svsp->name, svsp);
+	if (ret) {
+		dev_err(svsp->dev, "register irq(%d) failed: %d\n",
+			svsp_irq, ret);
+		goto svs_probe_iounmap;
+	}
+
 	ret = svs_start(svsp);
 	if (ret) {
 		dev_err(svsp->dev, "svs start fail: %d\n", ret);

---
base-commit: 4312098baf37ee17a8350725e6e0d0e8590252d4
change-id: 20221127-mtk-svs-add137fbf187

Best regards,
-- 
Ricardo Ribalda <ribalda@chromium.org>
