// SPDX-License-Identifier: GPL-2.0+
/*
* Hygon Processor Support for Linux
*
* Copyright (C) 2018 Chengdu Haiguang IC Design Co., Ltd.
*
* Author: Pu Wen <puwen@hygon.cn>
*/
#include <linux/io.h>
#include <asm/cpu.h>
#include <asm/smp.h>
#include <asm/cacheinfo.h>
#include <asm/spec-ctrl.h>
#include <asm/delay.h>
#ifdef [31mCONFIG_X86_64[0m
# include <asm/set_memory.h>
#endif
#include "cpu.h"
#define APICID_SOCKET_ID_BIT 6
/*
* nodes_per_socket: Stores the number of nodes per socket.
* Refer to CPUID Fn8000_001E_ECX Node Identifiers[10:8]
*/
static u32 nodes_per_socket = 1;
#ifdef [31mCONFIG_NUMA[0m
/*
* To workaround broken NUMA config. Read the comment in
* srat_detect_node().
*/
static int nearby_node(int apicid)
{
int i, node;
for (i = apicid - 1; i >= 0; i--) {
node = __apicid_to_node[i];
if (node != NUMA_NO_NODE && node_online(node))
return node;
}
for (i = apicid + 1; i < MAX_LOCAL_APIC; i++) {
node = __apicid_to_node[i];
if (node != NUMA_NO_NODE && node_online(node))
return node;
}
return first_node(node_online_map); /* Shouldn't happen */
}
#endif
static void hygon_get_topology_early(struct cpuinfo_x86 *c)
{
if (cpu_has(c, X86_FEATURE_TOPOEXT))
smp_num_siblings = ((cpuid_ebx(0x8000001e) >> 8) & 0xff) + 1;
}
/*
* Fixup core topology information for
* (1) Hygon multi-node processors
* Assumption: Number of cores in each internal node is the same.
* (2) Hygon processors supporting compute units
*/
static void hygon_get_topology(struct cpuinfo_x86 *c)
{
u8 node_id;
int cpu = smp_processor_id();
/* get information required for multi-node processors */
if (boot_cpu_has(X86_FEATURE_TOPOEXT)) {
int err;
u32 eax, ebx, ecx, edx;
cpuid(0x8000001e, &eax, &ebx, &ecx, &edx);
node_id = ecx & 0xff;
c->cpu_core_id = ebx & 0xff;
if (smp_num_siblings > 1)
c->x86_max_cores /= smp_num_siblings;
/*
* In case leaf B is available, use it to derive
* topology information.
*/
err = detect_extended_topology(c);
if (!err)
c->x86_coreid_bits = get_count_order(c->x86_max_cores);
/* Socket ID is ApicId[6] for these processors. */
c->phys_proc_id = c->apicid >> APICID_SOCKET_ID_BIT;
cacheinfo_hygon_init_llc_id(c, cpu, node_id);
} else if (cpu_has(c, X86_FEATURE_NODEID_MSR)) {
u64 value;
rdmsrl(MSR_FAM10H_NODE_ID, value);
node_id = value & 7;
per_cpu(cpu_llc_id, cpu) = node_id;
} else
return;
if (nodes_per_socket > 1)
set_cpu_cap(c, X86_FEATURE_AMD_DCM);
}
/*
* On Hygon setup the lower bits of the APIC id distinguish the cores.
* Assumes number of cores is a power of two.
*/
static void hygon_detect_cmp(struct cpuinfo_x86 *c)
{
unsigned int bits;
int cpu = smp_processor_id();
bits = c->x86_coreid_bits;
/* Low order bits define the core id (index of core in socket) */
c->cpu_core_id = c->initial_apicid & ((1 << bits)-1);
/* Convert the initial APIC ID into the socket ID */
c->phys_proc_id = c->initial_apicid >> bits;
/* use socket ID also for last level cache */
per_cpu(cpu_llc_id, cpu) = c->phys_proc_id;
}
static void srat_detect_node(struct cpuinfo_x86 *c)
{
#ifdef [31mCONFIG_NUMA[0m
int cpu = smp_processor_id();
int node;
unsigned int apicid = c->apicid;
node = numa_cpu_node(cpu);
if (node == NUMA_NO_NODE)
node = per_cpu(cpu_llc_id, cpu);
/*
* On multi-fabric platform (e.g. Numascale NumaChip) a
* platform-specific handler needs to be called to fixup some
* IDs of the CPU.
*/
if (x86_cpuinit.fixup_cpu_id)
x86_cpuinit.fixup_cpu_id(c, node);
if (!node_online(node)) {
/*
* Two possibilities here:
*
* - The CPU is missing memory and no node was created. In
* that case try picking one from a nearby CPU.
*
* - The APIC IDs differ from the HyperTransport node IDs.
* Assume they are all increased by a constant offset, but
* in the same order as the HT nodeids. If that doesn't
* result in a usable node fall back to the path for the
* previous case.
*
* This workaround operates directly on the mapping between
* APIC ID and NUMA node, assuming certain relationship
* between APIC ID, HT node ID and NUMA topology. As going
* through CPU mapping may alter the outcome, directly
* access __apicid_to_node[].
*/
int ht_nodeid = c->initial_apicid;
if (__apicid_to_node[ht_nodeid] != NUMA_NO_NODE)
node = __apicid_to_node[ht_nodeid];
/* Pick a nearby node */
if (!node_online(node))
node = nearby_node(apicid);
}
numa_set_node(cpu, node);
#endif
}
static void early_init_hygon_mc(struct cpuinfo_x86 *c)
{
#ifdef [31mCONFIG_SMP[0m
unsigned int bits, ecx;
/* Multi core CPU? */
if (c->extended_cpuid_level < 0x80000008)
return;
ecx = cpuid_ecx(0x80000008);
c->x86_max_cores = (ecx & 0xff) + 1;
/* CPU telling us the core id bits shift? */
bits = (ecx >> 12) & 0xF;
/* Otherwise recompute */
if (bits == 0) {
while ((1 << bits) < c->x86_max_cores)
bits++;
}
c->x86_coreid_bits = bits;
#endif
}
static void bsp_init_hygon(struct cpuinfo_x86 *c)
{
#ifdef [31mCONFIG_X86_64[0m
unsigned long long tseg;
/*
* Split up direct mapping around the TSEG SMM area.
* Don't do it for gbpages because there seems very little
* benefit in doing so.
*/
if (!rdmsrl_safe(MSR_K8_TSEG_ADDR, &tseg)) {
unsigned long pfn = tseg >> PAGE_SHIFT;
pr_debug("tseg: %010llx\n", tseg);
if (pfn_range_is_mapped(pfn, pfn + 1))
set_memory_4k((unsigned long)__va(tseg), 1);
}
#endif
if (cpu_has(c, X86_FEATURE_CONSTANT_TSC)) {
u64 val;
rdmsrl(MSR_K7_HWCR, val);
if (!(val & BIT(24)))
pr_warn(FW_BUG "TSC doesn't count with P0 frequency!\n");
}
if (cpu_has(c, X86_FEATURE_MWAITX))
use_mwaitx_delay();
if (boot_cpu_has(X86_FEATURE_TOPOEXT)) {
u32 ecx;
ecx = cpuid_ecx(0x8000001e);
nodes_per_socket = ((ecx >> 8) & 7) + 1;
} else if (boot_cpu_has(X86_FEATURE_NODEID_MSR)) {
u64 value;
rdmsrl(MSR_FAM10H_NODE_ID, value);
nodes_per_socket = ((value >> 3) & 7) + 1;
}
if (!boot_cpu_has(X86_FEATURE_AMD_SSBD) &&
!boot_cpu_has(X86_FEATURE_VIRT_SSBD)) {
/*
* Try to cache the base value so further operations can
* avoid RMW. If that faults, do not enable SSBD.
*/
if (!rdmsrl_safe(MSR_AMD64_LS_CFG, &x86_amd_ls_cfg_base)) {
setup_force_cpu_cap(X86_FEATURE_LS_CFG_SSBD);
setup_force_cpu_cap(X86_FEATURE_SSBD);
x86_amd_ls_cfg_ssbd_mask = 1ULL << 10;
}
}
}
static void early_init_hygon(struct cpuinfo_x86 *c)
{
u32 dummy;
early_init_hygon_mc(c);
set_cpu_cap(c, X86_FEATURE_K8);
rdmsr_safe(MSR_AMD64_PATCH_LEVEL, &c->microcode, &dummy);
/*
* c->x86_power is 8000_0007 edx. Bit 8 is TSC runs at constant rate
* with P/T states and does not stop in deep C-states
*/
if (c->x86_power & (1 << 8)) {
set_cpu_cap(c, X86_FEATURE_CONSTANT_TSC);
set_cpu_cap(c, X86_FEATURE_NONSTOP_TSC);
}
/* Bit 12 of 8000_0007 edx is accumulated power mechanism. */
if (c->x86_power & BIT(12))
set_cpu_cap(c, X86_FEATURE_ACC_POWER);
#ifdef [31mCONFIG_X86_64[0m
set_cpu_cap(c, X86_FEATURE_SYSCALL32);
#endif
#if defined([31mCONFIG_X86_LOCAL_APIC[0m) && defined([31mCONFIG_PCI[0m)
/*
* ApicID can always be treated as an 8-bit value for Hygon APIC So, we
* can safely set X86_FEATURE_EXTD_APICID unconditionally.
*/
if (boot_cpu_has(X86_FEATURE_APIC))
set_cpu_cap(c, X86_FEATURE_EXTD_APICID);
#endif
/*
* This is only needed to tell the kernel whether to use VMCALL
* and VMMCALL. VMMCALL is never executed except under virt, so
* we can set it unconditionally.
*/
set_cpu_cap(c, X86_FEATURE_VMMCALL);
hygon_get_topology_early(c);
}
static void init_hygon(struct cpuinfo_x86 *c)
{
early_init_hygon(c);
/*
* Bit 31 in normal CPUID used for nonstandard 3DNow ID;
* 3DNow is IDd by bit 31 in extended CPUID (1*32+31) anyway
*/
clear_cpu_cap(c, 0*32+31);
set_cpu_cap(c, X86_FEATURE_REP_GOOD);
/* get apicid instead of initial apic id from cpuid */
c->apicid = hard_smp_processor_id();
set_cpu_cap(c, X86_FEATURE_ZEN);
set_cpu_cap(c, X86_FEATURE_CPB);
cpu_detect_cache_sizes(c);
hygon_detect_cmp(c);
hygon_get_topology(c);
srat_detect_node(c);
init_hygon_cacheinfo(c);
if (cpu_has(c, X86_FEATURE_XMM2)) {
/*
* Use LFENCE for execution serialization. On families which
* don't have that MSR, LFENCE is already serializing.
* msr_set_bit() uses the safe accessors, too, even if the MSR
* is not present.
*/
msr_set_bit(MSR_F10H_DECFG,
MSR_F10H_DECFG_LFENCE_SERIALIZE_BIT);
/* A serializing LFENCE stops RDTSC speculation */
set_cpu_cap(c, X86_FEATURE_LFENCE_RDTSC);
}
/*
* Hygon processors have APIC timer running in deep C states.
*/
set_cpu_cap(c, X86_FEATURE_ARAT);
/* Hygon CPUs don't reset SS attributes on SYSRET, Xen does. */
if (!cpu_has(c, X86_FEATURE_XENPV))
set_cpu_bug(c, X86_BUG_SYSRET_SS_ATTRS);
}
static void cpu_detect_tlb_hygon(struct cpuinfo_x86 *c)
{
u32 ebx, eax, ecx, edx;
u16 mask = 0xfff;
if (c->extended_cpuid_level < 0x80000006)
return;
cpuid(0x80000006, &eax, &ebx, &ecx, &edx);
tlb_lld_4k[ENTRIES] = (ebx >> 16) & mask;
tlb_lli_4k[ENTRIES] = ebx & mask;
/* Handle DTLB 2M and 4M sizes, fall back to L1 if L2 is disabled */
if (!((eax >> 16) & mask))
tlb_lld_2m[ENTRIES] = (cpuid_eax(0x80000005) >> 16) & 0xff;
else
tlb_lld_2m[ENTRIES] = (eax >> 16) & mask;
/* a 4M entry uses two 2M entries */
tlb_lld_4m[ENTRIES] = tlb_lld_2m[ENTRIES] >> 1;
/* Handle ITLB 2M and 4M sizes, fall back to L1 if L2 is disabled */
if (!(eax & mask)) {
cpuid(0x80000005, &eax, &ebx, &ecx, &edx);
tlb_lli_2m[ENTRIES] = eax & 0xff;
} else
tlb_lli_2m[ENTRIES] = eax & mask;
tlb_lli_4m[ENTRIES] = tlb_lli_2m[ENTRIES] >> 1;
}
static const struct cpu_dev hygon_cpu_dev = {
.c_vendor = "Hygon",
.c_ident = { "HygonGenuine" },
.c_early_init = early_init_hygon,
.c_detect_tlb = cpu_detect_tlb_hygon,
.c_bsp_init = bsp_init_hygon,
.c_init = init_hygon,
.c_x86_vendor = X86_VENDOR_HYGON,
};
cpu_dev_register(hygon_cpu_dev);