2026-01-29 22:25:33 +08:00

168 lines
4.9 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
/* Copyright (C) 2021 Arm Ltd. */
#ifndef __ASM__MPAM_H
#define __ASM__MPAM_H
#include <linux/arm_mpam.h>
#include <linux/bitops.h>
#include <linux/bitfield.h>
#include <linux/init.h>
#include <linux/jump_label.h>
#include <linux/percpu.h>
#include <linux/sched.h>
#include <asm/cpucaps.h>
#include <asm/cpufeature.h>
#include <asm/sysreg.h>
/* CPU Registers */
#define MPAM_SYSREG_EN BIT_ULL(63)
#define MPAM_SYSREG_TRAP_IDR BIT_ULL(58)
#define MPAM_SYSREG_TRAP_MPAM0_EL1 BIT_ULL(49)
#define MPAM_SYSREG_TRAP_MPAM1_EL1 BIT_ULL(48)
#define MPAM_SYSREG_PMG_D GENMASK(47, 40)
#define MPAM_SYSREG_PMG_I GENMASK(39, 32)
#define MPAM_SYSREG_PARTID_D GENMASK(31, 16)
#define MPAM_SYSREG_PARTID_I GENMASK(15, 0)
#define MPAMIDR_PMG_MAX GENMASK(40, 32)
#define MPAMIDR_PMG_MAX_SHIFT 32
#define MPAMIDR_PMG_MAX_LEN 8
#define MPAMIDR_VPMR_MAX GENMASK(20, 18)
#define MPAMIDR_VPMR_MAX_SHIFT 18
#define MPAMIDR_VPMR_MAX_LEN 3
#define MPAMIDR_HAS_HCR BIT(17)
#define MPAMIDR_HAS_HCR_SHIFT 17
#define MPAMIDR_PARTID_MAX GENMASK(15, 0)
#define MPAMIDR_PARTID_MAX_SHIFT 0
#define MPAMIDR_PARTID_MAX_LEN 15
#define MPAMHCR_EL0_VPMEN BIT_ULL(0)
#define MPAMHCR_EL1_VPMEN BIT_ULL(1)
#define MPAMHCR_GSTAPP_PLK BIT_ULL(8)
#define MPAMHCR_TRAP_MPAMIDR BIT_ULL(31)
/* Properties of the VPM registers */
#define MPAM_VPM_NUM_REGS 8
#define MPAM_VPM_PARTID_LEN 16
#define MPAM_VPM_PARTID_MASK 0xffff
#define MPAM_VPM_REG_LEN 64
#define MPAM_VPM_PARTIDS_PER_REG (MPAM_VPM_REG_LEN / MPAM_VPM_PARTID_LEN)
#define MPAM_VPM_MAX_PARTID (MPAM_VPM_NUM_REGS * MPAM_VPM_PARTIDS_PER_REG)
DECLARE_STATIC_KEY_FALSE(arm64_mpam_has_hcr);
DECLARE_STATIC_KEY_FALSE(mpam_enabled);
DECLARE_PER_CPU(u64, arm64_mpam_default);
DECLARE_PER_CPU(u64, arm64_mpam_current);
/* check whether all CPUs have MPAM support */
static __always_inline bool mpam_cpus_have_feature(void)
{
if (IS_ENABLED(CONFIG_ARM64_MPAM))
return cpus_have_final_cap(ARM64_MPAM);
return false;
}
/* check whether all CPUs have MPAM virtualisation support */
static __always_inline bool mpam_cpus_have_mpam_hcr(void)
{
if (IS_ENABLED(CONFIG_ARM64_MPAM))
return static_branch_unlikely(&arm64_mpam_has_hcr);
return false;
}
/* enable MPAM virtualisation support */
static inline void __init __enable_mpam_hcr(void)
{
if (IS_ENABLED(CONFIG_ARM64_MPAM))
static_branch_enable(&arm64_mpam_has_hcr);
}
/*
* The resctrl filesystem writes to the partid/pmg values for threads and CPUs,
* which may race with reads in __mpam_sched_in(). Ensure only one of the old
* or new values are used. Particular care should be taken with the pmg field
* as __mpam_sched_in() may read a partid and pmg that don't match, causing
* this value to be stored with cache allocations, despite being considered
* 'free' by resctrl.
*
* A value in struct thread_info is used instead of struct task_struct as the
* cpu's u64 register format is used, but struct task_struct has two u32'.
*/
static inline void mpam_set_cpu_defaults(int cpu, u16 partid_d, u16 partid_i,
u8 pmg_d, u8 pmg_i)
{
u64 default_val;
default_val = FIELD_PREP(MPAM_SYSREG_PARTID_D, partid_d);
default_val |= FIELD_PREP(MPAM_SYSREG_PARTID_I, partid_i);
default_val |= FIELD_PREP(MPAM_SYSREG_PMG_D, pmg_d);
default_val |= FIELD_PREP(MPAM_SYSREG_PMG_I, pmg_i);
WRITE_ONCE(per_cpu(arm64_mpam_default, cpu), default_val);
}
static inline void mpam_set_task_partid_pmg(struct task_struct *tsk,
u16 partid_d, u16 partid_i,
u8 pmg_d, u8 pmg_i)
{
#ifdef CONFIG_ARM64_MPAM
u64 regval;
regval = FIELD_PREP(MPAM_SYSREG_PARTID_D, partid_d);
regval |= FIELD_PREP(MPAM_SYSREG_PARTID_I, partid_i);
regval |= FIELD_PREP(MPAM_SYSREG_PMG_D, pmg_d);
regval |= FIELD_PREP(MPAM_SYSREG_PMG_I, pmg_i);
WRITE_ONCE(task_thread_info(tsk)->mpam_partid_pmg, regval);
#endif
}
static inline u64 mpam_get_regval(struct task_struct *tsk)
{
#ifdef CONFIG_ARM64_MPAM
return READ_ONCE(task_thread_info(tsk)->mpam_partid_pmg);
#else
return 0;
#endif
}
static inline void resctrl_arch_set_rmid(struct task_struct *tsk, u32 rmid)
{
#ifdef CONFIG_ARM64_MPAM
u64 regval = mpam_get_regval(tsk);
regval &= ~MPAM_SYSREG_PMG_D;
regval &= ~MPAM_SYSREG_PMG_I;
regval |= FIELD_PREP(MPAM_SYSREG_PMG_D, rmid);
regval |= FIELD_PREP(MPAM_SYSREG_PMG_I, rmid);
WRITE_ONCE(task_thread_info(tsk)->mpam_partid_pmg, regval);
#endif
}
static inline void mpam_thread_switch(struct task_struct *tsk)
{
u64 oldregval;
int cpu = smp_processor_id();
u64 regval = mpam_get_regval(tsk);
if (!IS_ENABLED(CONFIG_ARM64_MPAM) ||
!static_branch_likely(&mpam_enabled))
return;
if (regval == READ_ONCE(mpam_resctrl_default_group))
regval = READ_ONCE(per_cpu(arm64_mpam_default, cpu));
oldregval = READ_ONCE(per_cpu(arm64_mpam_current, cpu));
if (oldregval == regval)
return;
/* Synchronising this write is left until the ERET to EL0 */
write_sysreg_s(regval, SYS_MPAM0_EL1);
WRITE_ONCE(per_cpu(arm64_mpam_current, cpu), regval);
}
#endif /* __ASM__MPAM_H */