x86/amd_node: Fix PCI device reference counting in amd_smn_init()grafted

The local "root" pointer is a temporary variable used during the device
search. Therefore, refcount related to the search iterators should be cleaned
up after the search is complete.

Use the __free() cleanup macro to ensure the refcount is decremented when the
temporary pointer goes out of scope.

Additionally, increment the refcount when caching a root pointer. This ensures
the in-use refcount is separate from the temporary search refcounting.

Finally, drop the redundant "root = NULL" before the second search loop. The
pci_get_class() iterator always decrements the refcount of its "from"
argument, so the first loop can only fall through with "root" already NULL.

Fixes: 0a4b61d9c2e4 ("x86/amd_node: Fix AMD root device caching")
Closes: https://sashiko.dev/#/patchset/20260806160159.230453-1-jason.andryuk%40amd.com
Reported-by: Sashiko <sashiko-bot@kernel.org>
Assisted-by: LLM
Signed-off-by: Yazen Ghannam <yazen.ghannam@amd.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Mario Limonciello (AMD) <superm1@kernel.org>
Cc: <stable@kernel.org>
Link: https://patch.msgid.link/20260903154325.74343-1-yazen.ghannam@amd.com

1 files changed, 62 insertions, 0 deletions

diff --git a/include/dt-bindings/clock/bcm2835.h b/include/dt-bindings/clock/bcm2835.h
new file mode 100644
index 000000000..b60c03430
--- /dev/null
+++ b/include/dt-bindings/clock/bcm2835.h
@@ -0,0 +1,62 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2015 Broadcom Corporation
+ */
+
+#define BCM2835_PLLA			0
+#define BCM2835_PLLB			1
+#define BCM2835_PLLC			2
+#define BCM2835_PLLD			3
+#define BCM2835_PLLH			4
+
+#define BCM2835_PLLA_CORE		5
+#define BCM2835_PLLA_PER		6
+#define BCM2835_PLLB_ARM		7
+#define BCM2835_PLLC_CORE0		8
+#define BCM2835_PLLC_CORE1		9
+#define BCM2835_PLLC_CORE2		10
+#define BCM2835_PLLC_PER		11
+#define BCM2835_PLLD_CORE		12
+#define BCM2835_PLLD_PER		13
+#define BCM2835_PLLH_RCAL		14
+#define BCM2835_PLLH_AUX		15
+#define BCM2835_PLLH_PIX		16
+
+#define BCM2835_CLOCK_TIMER		17
+#define BCM2835_CLOCK_OTP		18
+#define BCM2835_CLOCK_UART		19
+#define BCM2835_CLOCK_VPU		20
+#define BCM2835_CLOCK_V3D		21
+#define BCM2835_CLOCK_ISP		22
+#define BCM2835_CLOCK_H264		23
+#define BCM2835_CLOCK_VEC		24
+#define BCM2835_CLOCK_HSM		25
+#define BCM2835_CLOCK_SDRAM		26
+#define BCM2835_CLOCK_TSENS		27
+#define BCM2835_CLOCK_EMMC		28
+#define BCM2835_CLOCK_PERI_IMAGE	29
+#define BCM2835_CLOCK_PWM		30
+#define BCM2835_CLOCK_PCM		31
+
+#define BCM2835_PLLA_DSI0		32
+#define BCM2835_PLLA_CCP2		33
+#define BCM2835_PLLD_DSI0		34
+#define BCM2835_PLLD_DSI1		35
+
+#define BCM2835_CLOCK_AVEO		36
+#define BCM2835_CLOCK_DFT		37
+#define BCM2835_CLOCK_GP0		38
+#define BCM2835_CLOCK_GP1		39
+#define BCM2835_CLOCK_GP2		40
+#define BCM2835_CLOCK_SLIM		41
+#define BCM2835_CLOCK_SMI		42
+#define BCM2835_CLOCK_TEC		43
+#define BCM2835_CLOCK_DPI		44
+#define BCM2835_CLOCK_CAM0		45
+#define BCM2835_CLOCK_CAM1		46
+#define BCM2835_CLOCK_DSI0E		47
+#define BCM2835_CLOCK_DSI1E		48
+#define BCM2835_CLOCK_DSI0P		49
+#define BCM2835_CLOCK_DSI1P		50
+
+#define BCM2711_CLOCK_EMMC2		51