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, 82 insertions, 0 deletions

diff --git a/include/dt-bindings/clock/bm1880-clock.h b/include/dt-bindings/clock/bm1880-clock.h
new file mode 100644
index 000000000..b46732361
--- /dev/null
+++ b/include/dt-bindings/clock/bm1880-clock.h
@@ -0,0 +1,82 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Device Tree binding constants for Bitmain BM1880 SoC
+ *
+ * Copyright (c) 2019 Linaro Ltd.
+ */
+
+#ifndef __DT_BINDINGS_CLOCK_BM1880_H
+#define __DT_BINDINGS_CLOCK_BM1880_H
+
+#define BM1880_CLK_OSC			0
+#define BM1880_CLK_MPLL			1
+#define BM1880_CLK_SPLL			2
+#define BM1880_CLK_FPLL			3
+#define BM1880_CLK_DDRPLL		4
+#define BM1880_CLK_A53			5
+#define BM1880_CLK_50M_A53		6
+#define BM1880_CLK_AHB_ROM		7
+#define BM1880_CLK_AXI_SRAM		8
+#define BM1880_CLK_DDR_AXI		9
+#define BM1880_CLK_EFUSE		10
+#define BM1880_CLK_APB_EFUSE		11
+#define BM1880_CLK_AXI5_EMMC		12
+#define BM1880_CLK_EMMC			13
+#define BM1880_CLK_100K_EMMC		14
+#define BM1880_CLK_AXI5_SD		15
+#define BM1880_CLK_SD			16
+#define BM1880_CLK_100K_SD		17
+#define BM1880_CLK_500M_ETH0		18
+#define BM1880_CLK_AXI4_ETH0		19
+#define BM1880_CLK_500M_ETH1		20
+#define BM1880_CLK_AXI4_ETH1		21
+#define BM1880_CLK_AXI1_GDMA		22
+#define BM1880_CLK_APB_GPIO		23
+#define BM1880_CLK_APB_GPIO_INTR	24
+#define BM1880_CLK_GPIO_DB		25
+#define BM1880_CLK_AXI1_MINER		26
+#define BM1880_CLK_AHB_SF		27
+#define BM1880_CLK_SDMA_AXI		28
+#define BM1880_CLK_SDMA_AUD		29
+#define BM1880_CLK_APB_I2C		30
+#define BM1880_CLK_APB_WDT		31
+#define BM1880_CLK_APB_JPEG		32
+#define BM1880_CLK_JPEG_AXI		33
+#define BM1880_CLK_AXI5_NF		34
+#define BM1880_CLK_APB_NF		35
+#define BM1880_CLK_NF			36
+#define BM1880_CLK_APB_PWM		37
+#define BM1880_CLK_DIV_0_RV		38
+#define BM1880_CLK_DIV_1_RV		39
+#define BM1880_CLK_MUX_RV		40
+#define BM1880_CLK_RV			41
+#define BM1880_CLK_APB_SPI		42
+#define BM1880_CLK_TPU_AXI		43
+#define BM1880_CLK_DIV_UART_500M	44
+#define BM1880_CLK_UART_500M		45
+#define BM1880_CLK_APB_UART		46
+#define BM1880_CLK_APB_I2S		47
+#define BM1880_CLK_AXI4_USB		48
+#define BM1880_CLK_APB_USB		49
+#define BM1880_CLK_125M_USB		50
+#define BM1880_CLK_33K_USB		51
+#define BM1880_CLK_DIV_12M_USB		52
+#define BM1880_CLK_12M_USB		53
+#define BM1880_CLK_APB_VIDEO		54
+#define BM1880_CLK_VIDEO_AXI		55
+#define BM1880_CLK_VPP_AXI		56
+#define BM1880_CLK_APB_VPP		57
+#define BM1880_CLK_DIV_0_AXI1		58
+#define BM1880_CLK_DIV_1_AXI1		59
+#define BM1880_CLK_AXI1			60
+#define BM1880_CLK_AXI2			61
+#define BM1880_CLK_AXI3			62
+#define BM1880_CLK_AXI4			63
+#define BM1880_CLK_AXI5			64
+#define BM1880_CLK_DIV_0_AXI6		65
+#define BM1880_CLK_DIV_1_AXI6		66
+#define BM1880_CLK_MUX_AXI6		67
+#define BM1880_CLK_AXI6			68
+#define BM1880_NR_CLKS			69
+
+#endif /* __DT_BINDINGS_CLOCK_BM1880_H */