From 27600805e62f800bacf990354632eae4e487d34c Mon Sep 17 00:00:00 2001 From: Yazen Ghannam Date: Thu, 3 Sep 2026 10:43:25 -0500 Subject: x86/amd_node: Fix PCI device reference counting in amd_smn_init() 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 Assisted-by: LLM Signed-off-by: Yazen Ghannam Signed-off-by: Borislav Petkov (AMD) Reviewed-by: Mario Limonciello (AMD) Cc: Link: https://patch.msgid.link/20260903154325.74343-1-yazen.ghannam@amd.com --- arch/powerpc/sysdev/grackle.c | 43 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 43 insertions(+) create mode 100644 arch/powerpc/sysdev/grackle.c (limited to 'arch/powerpc/sysdev/grackle.c') diff --git a/arch/powerpc/sysdev/grackle.c b/arch/powerpc/sysdev/grackle.c new file mode 100644 index 000000000..7dce8278b --- /dev/null +++ b/arch/powerpc/sysdev/grackle.c @@ -0,0 +1,43 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Functions for setting up and using a MPC106 northbridge + * Extracted from arch/powerpc/platforms/powermac/pci.c. + * + * Copyright (C) 2003 Benjamin Herrenschmuidt (benh@kernel.crashing.org) + * Copyright (C) 1997 Paul Mackerras (paulus@samba.org) + */ +#include +#include +#include +#include + +#include +#include +#include + +#define GRACKLE_CFA(b, d, o) (0x80 | ((b) << 8) | ((d) << 16) \ + | (((o) & ~3) << 24)) + +#define GRACKLE_PICR1_LOOPSNOOP 0x00000010 + +static inline void grackle_set_loop_snoop(struct pci_controller *bp, int enable) +{ + unsigned int val; + + out_be32(bp->cfg_addr, GRACKLE_CFA(0, 0, 0xa8)); + val = in_le32(bp->cfg_data); + val = enable? (val | GRACKLE_PICR1_LOOPSNOOP) : + (val & ~GRACKLE_PICR1_LOOPSNOOP); + out_be32(bp->cfg_addr, GRACKLE_CFA(0, 0, 0xa8)); + out_le32(bp->cfg_data, val); + (void)in_le32(bp->cfg_data); +} + +void __init setup_grackle(struct pci_controller *hose) +{ + setup_indirect_pci(hose, 0xfec00000, 0xfee00000, 0); + if (of_machine_is_compatible("PowerMac1,1")) + pci_add_flags(PCI_REASSIGN_ALL_BUS); + if (of_machine_is_compatible("AAPL,PowerBook1998")) + grackle_set_loop_snoop(hose, 1); +} -- cgit v1.3.1