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, 66 insertions, 0 deletions

diff --git a/include/dt-bindings/clock/at91.h b/include/dt-bindings/clock/at91.h
new file mode 100644
index 000000000..f2a7b7d39
--- /dev/null
+++ b/include/dt-bindings/clock/at91.h
@@ -0,0 +1,66 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * This header provides constants for AT91 pmc status.
+ *
+ * The constants defined in this header are being used in dts.
+ */
+
+#ifndef _DT_BINDINGS_CLK_AT91_H
+#define _DT_BINDINGS_CLK_AT91_H
+
+#define PMC_TYPE_CORE		0
+#define PMC_TYPE_SYSTEM		1
+#define PMC_TYPE_PERIPHERAL	2
+#define PMC_TYPE_GCK		3
+#define PMC_TYPE_PROGRAMMABLE	4
+
+#define PMC_SLOW		0
+#define PMC_MCK			1
+#define PMC_UTMI		2
+#define PMC_MAIN		3
+#define PMC_MCK2		4
+#define PMC_I2S0_MUX		5
+#define PMC_I2S1_MUX		6
+#define PMC_PLLACK		7
+#define PMC_PLLBCK		8
+#define PMC_AUDIOPLLCK		9
+#define PMC_AUDIOPINCK		10
+
+/* SAMA7G5 */
+#define PMC_CPUPLL		(PMC_MAIN + 1)
+#define PMC_SYSPLL		(PMC_MAIN + 2)
+#define PMC_DDRPLL		(PMC_MAIN + 3)
+#define PMC_IMGPLL		(PMC_MAIN + 4)
+#define PMC_BAUDPLL		(PMC_MAIN + 5)
+#define PMC_AUDIOPMCPLL		(PMC_MAIN + 6)
+#define PMC_AUDIOIOPLL		(PMC_MAIN + 7)
+#define PMC_ETHPLL		(PMC_MAIN + 8)
+#define PMC_CPU			(PMC_MAIN + 9)
+#define PMC_MCK1		(PMC_MAIN + 10)
+
+/* SAM9X7 */
+#define PMC_PLLADIV2		(PMC_MAIN + 11)
+#define PMC_LVDSPLL		(PMC_MAIN + 12)
+
+/* SAMA7D65 */
+#define PMC_MCK3		(PMC_MAIN + 13)
+#define PMC_MCK5		(PMC_MAIN + 14)
+
+#ifndef AT91_PMC_MOSCS
+#define AT91_PMC_MOSCS		0		/* MOSCS Flag */
+#define AT91_PMC_LOCKA		1		/* PLLA Lock */
+#define AT91_PMC_LOCKB		2		/* PLLB Lock */
+#define AT91_PMC_MCKRDY		3		/* Master Clock */
+#define AT91_PMC_LOCKU		6		/* UPLL Lock */
+#define AT91_PMC_PCKRDY(id)	(8 + (id))	/* Programmable Clock */
+#define AT91_PMC_MOSCSELS	16		/* Main Oscillator Selection */
+#define AT91_PMC_MOSCRCS	17		/* Main On-Chip RC */
+#define AT91_PMC_CFDEV		18		/* Clock Failure Detector Event */
+#define AT91_PMC_GCKRDY		24		/* Generated Clocks */
+#endif
+
+/* Slow clock. */
+#define SCKC_MD_SLCK		0
+#define SCKC_TD_SLCK		1
+
+#endif