Merge tag 'x86_misc_for_v6.14_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull misc x86 updates from Borislav Petkov:

 - The first part of a restructuring of AMD's representation of a
   northbridge which is legacy now, and the creation of the new AMD node
   concept which represents the Zen architecture of having a collection
   of I/O devices within an SoC. Those nodes comprise the so-called data
   fabric on Zen.

   This has at least one practical advantage of not having to add a PCI
   ID each time a new data fabric PCI device releases. Eventually, the
   lot more uniform provider of data fabric functionality amd_node.c
   will be used by all the drivers which need it

 - Smaller cleanups

* tag 'x86_misc_for_v6.14_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/amd_node: Use defines for SMN register offsets
  x86/amd_node: Remove dependency on AMD_NB
  x86/amd_node: Update __amd_smn_rw() error paths
  x86/amd_nb: Move SMN access code to a new amd_node driver
  x86/amd_nb, hwmon: (k10temp): Simplify amd_pci_dev_to_node_id()
  x86/amd_nb: Simplify function 3 search
  x86/amd_nb: Use topology info to get AMD node count
  x86/amd_nb: Simplify root device search
  x86/amd_nb: Simplify function 4 search
  x86: Start moving AMD node functionality out of AMD_NB
  x86/amd_nb: Clean up early_is_amd_nb()
  x86/amd_nb: Restrict init function to AMD-based systems
  x86/mtrr: Rename mtrr_overwrite_state() to guest_force_mtrr_state()

Author: torvalds

MAINTAINERS

@@ -1120,6 +1120,14 @@ L:	linux-i2c@vger.kernel.org
 S:	Supported
 F:	drivers/i2c/busses/i2c-amd-asf-plat.c
 
+AMD NODE DRIVER
+M:	Mario Limonciello <mario.limonciello@amd.com>
+M:	Yazen Ghannam <yazen.ghannam@amd.com>
+L:	linux-kernel@vger.kernel.org
+S:	Supported
+F:	arch/x86/include/asm/amd_node.h
+F:	arch/x86/kernel/amd_node.c
+
 AMD PDS CORE DRIVER
 M:	Shannon Nelson <shannon.nelson@amd.com>
 M:	Brett Creeley <brett.creeley@amd.com>

arch/x86/Kconfig

@@ -3128,6 +3128,10 @@ config TS5500
 endif # X86_32
 
 config AMD_NB
+	def_bool y
+	depends on AMD_NODE
+
+config AMD_NODE
 	def_bool y
 	depends on CPU_SUP_AMD && PCI
 

arch/x86/hyperv/ivm.c

@@ -664,7 +664,7 @@ void __init hv_vtom_init(void)
 	x86_platform.guest.enc_status_change_finish = hv_vtom_set_host_visibility;
 
 	/* Set WB as the default cache mode. */
-	mtrr_overwrite_state(NULL, 0, MTRR_TYPE_WRBACK);
+	guest_force_mtrr_state(NULL, 0, MTRR_TYPE_WRBACK);
 }
 
 #endif /* defined(CONFIG_AMD_MEM_ENCRYPT) || defined(CONFIG_INTEL_TDX_GUEST) */

arch/x86/include/asm/amd_nb.h

@@ -4,6 +4,7 @@
 
 #include <linux/ioport.h>
 #include <linux/pci.h>
+#include <asm/amd_node.h>
 
 struct amd_nb_bus_dev_range {
 	u8 bus;
@@ -20,9 +21,6 @@ extern int amd_numa_init(void);
 extern int amd_get_subcaches(int);
 extern int amd_set_subcaches(int, unsigned long);
 
-int __must_check amd_smn_read(u16 node, u32 address, u32 *value);
-int __must_check amd_smn_write(u16 node, u32 address, u32 value);
-
 struct amd_l3_cache {
 	unsigned indices;
 	u8	 subcaches[4];
@@ -51,23 +49,6 @@ u16 amd_nb_num(void);
 bool amd_nb_has_feature(unsigned int feature);
 struct amd_northbridge *node_to_amd_nb(int node);
 
-static inline u16 amd_pci_dev_to_node_id(struct pci_dev *pdev)
-{
-	struct pci_dev *misc;
-	int i;
-
-	for (i = 0; i != amd_nb_num(); i++) {
-		misc = node_to_amd_nb(i)->misc;
-
-		if (pci_domain_nr(misc->bus) == pci_domain_nr(pdev->bus) &&
-		    PCI_SLOT(misc->devfn) == PCI_SLOT(pdev->devfn))
-			return i;
-	}
-
-	WARN(1, "Unable to find AMD Northbridge id for %s\n", pci_name(pdev));
-	return 0;
-}
-
 static inline bool amd_gart_present(void)
 {
 	if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD)

arch/x86/include/asm/amd_node.h

@@ -0,0 +1,36 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * AMD Node helper functions and common defines
+ *
+ * Copyright (c) 2024, Advanced Micro Devices, Inc.
+ * All Rights Reserved.
+ *
+ * Author: Yazen Ghannam <Yazen.Ghannam@amd.com>
+ *
+ * Note:
+ * Items in this file may only be used in a single place.
+ * However, it's prudent to keep all AMD Node functionality
+ * in a unified place rather than spreading throughout the
+ * kernel.
+ */
+
+#ifndef _ASM_X86_AMD_NODE_H_
+#define _ASM_X86_AMD_NODE_H_
+
+#include <linux/pci.h>
+
+#define MAX_AMD_NUM_NODES	8
+#define AMD_NODE0_PCI_SLOT	0x18
+
+struct pci_dev *amd_node_get_func(u16 node, u8 func);
+struct pci_dev *amd_node_get_root(u16 node);
+
+static inline u16 amd_num_nodes(void)
+{
+	return topology_amd_nodes_per_pkg() * topology_max_packages();
+}
+
+int __must_check amd_smn_read(u16 node, u32 address, u32 *value);
+int __must_check amd_smn_write(u16 node, u32 address, u32 value);
+
+#endif /*_ASM_X86_AMD_NODE_H_*/

arch/x86/include/asm/mtrr.h

@@ -58,8 +58,8 @@ struct mtrr_state_type {
  */
 # ifdef CONFIG_MTRR
 void mtrr_bp_init(void);
-void mtrr_overwrite_state(struct mtrr_var_range *var, unsigned int num_var,
-			  mtrr_type def_type);
+void guest_force_mtrr_state(struct mtrr_var_range *var, unsigned int num_var,
+			    mtrr_type def_type);
 extern u8 mtrr_type_lookup(u64 addr, u64 end, u8 *uniform);
 extern void mtrr_save_fixed_ranges(void *);
 extern void mtrr_save_state(void);
@@ -75,9 +75,9 @@ void mtrr_disable(void);
 void mtrr_enable(void);
 void mtrr_generic_set_state(void);
 #  else
-static inline void mtrr_overwrite_state(struct mtrr_var_range *var,
-					unsigned int num_var,
-					mtrr_type def_type)
+static inline void guest_force_mtrr_state(struct mtrr_var_range *var,
+					  unsigned int num_var,
+					  mtrr_type def_type)
 {
 }
 

arch/x86/kernel/Makefile

@@ -119,6 +119,7 @@ obj-$(CONFIG_EARLY_PRINTK)	+= early_printk.o
 obj-$(CONFIG_HPET_TIMER) 	+= hpet.o
 
 obj-$(CONFIG_AMD_NB)		+= amd_nb.o
+obj-$(CONFIG_AMD_NODE)		+= amd_node.o
 obj-$(CONFIG_DEBUG_NMI_SELFTEST) += nmi_selftest.o
 
 obj-$(CONFIG_KVM_GUEST)		+= kvm.o kvmclock.o