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, 77 insertions, 0 deletions

diff --git a/include/dt-bindings/clock/mpc512x-clock.h b/include/dt-bindings/clock/mpc512x-clock.h
new file mode 100644
index 000000000..13c316bf2
--- /dev/null
+++ b/include/dt-bindings/clock/mpc512x-clock.h
@@ -0,0 +1,77 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * This header provides constants for MPC512x clock specs in DT bindings.
+ */
+
+#ifndef _DT_BINDINGS_CLOCK_MPC512x_CLOCK_H
+#define _DT_BINDINGS_CLOCK_MPC512x_CLOCK_H
+
+#define MPC512x_CLK_DUMMY		0
+#define MPC512x_CLK_REF			1
+#define MPC512x_CLK_SYS			2
+#define MPC512x_CLK_DIU			3
+#define MPC512x_CLK_VIU			4
+#define MPC512x_CLK_CSB			5
+#define MPC512x_CLK_E300		6
+#define MPC512x_CLK_IPS			7
+#define MPC512x_CLK_FEC			8
+#define MPC512x_CLK_SATA		9
+#define MPC512x_CLK_PATA		10
+#define MPC512x_CLK_NFC			11
+#define MPC512x_CLK_LPC			12
+#define MPC512x_CLK_MBX_BUS		13
+#define MPC512x_CLK_MBX			14
+#define MPC512x_CLK_MBX_3D		15
+#define MPC512x_CLK_AXE			16
+#define MPC512x_CLK_USB1		17
+#define MPC512x_CLK_USB2		18
+#define MPC512x_CLK_I2C			19
+#define MPC512x_CLK_MSCAN0_MCLK		20
+#define MPC512x_CLK_MSCAN1_MCLK		21
+#define MPC512x_CLK_MSCAN2_MCLK		22
+#define MPC512x_CLK_MSCAN3_MCLK		23
+#define MPC512x_CLK_BDLC		24
+#define MPC512x_CLK_SDHC		25
+#define MPC512x_CLK_PCI			26
+#define MPC512x_CLK_PSC_MCLK_IN		27
+#define MPC512x_CLK_SPDIF_TX		28
+#define MPC512x_CLK_SPDIF_RX		29
+#define MPC512x_CLK_SPDIF_MCLK		30
+#define MPC512x_CLK_SPDIF		31
+#define MPC512x_CLK_AC97		32
+#define MPC512x_CLK_PSC0_MCLK		33
+#define MPC512x_CLK_PSC1_MCLK		34
+#define MPC512x_CLK_PSC2_MCLK		35
+#define MPC512x_CLK_PSC3_MCLK		36
+#define MPC512x_CLK_PSC4_MCLK		37
+#define MPC512x_CLK_PSC5_MCLK		38
+#define MPC512x_CLK_PSC6_MCLK		39
+#define MPC512x_CLK_PSC7_MCLK		40
+#define MPC512x_CLK_PSC8_MCLK		41
+#define MPC512x_CLK_PSC9_MCLK		42
+#define MPC512x_CLK_PSC10_MCLK		43
+#define MPC512x_CLK_PSC11_MCLK		44
+#define MPC512x_CLK_PSC_FIFO		45
+#define MPC512x_CLK_PSC0		46
+#define MPC512x_CLK_PSC1		47
+#define MPC512x_CLK_PSC2		48
+#define MPC512x_CLK_PSC3		49
+#define MPC512x_CLK_PSC4		50
+#define MPC512x_CLK_PSC5		51
+#define MPC512x_CLK_PSC6		52
+#define MPC512x_CLK_PSC7		53
+#define MPC512x_CLK_PSC8		54
+#define MPC512x_CLK_PSC9		55
+#define MPC512x_CLK_PSC10		56
+#define MPC512x_CLK_PSC11		57
+#define MPC512x_CLK_SDHC2		58
+#define MPC512x_CLK_FEC2		59
+#define MPC512x_CLK_OUT0_CLK		60
+#define MPC512x_CLK_OUT1_CLK		61
+#define MPC512x_CLK_OUT2_CLK		62
+#define MPC512x_CLK_OUT3_CLK		63
+#define MPC512x_CLK_CAN_CLK_IN		64
+
+#define MPC512x_CLK_LAST_PUBLIC		64
+
+#endif