// SPDX-License-Identifier: GPL-2.0
/*
 * Performance events support for SH-4A performance counters
 *
 *  Copyright (C) 2009, 2010  Paul Mundt
 */
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/io.h>
#include <linux/irq.h>
#include <linux/perf_event.h>
#include <asm/processor.h>

#define PPC_CCBR(idx)   (0xff200800 + (sizeof(u32) * idx))
#define PPC_PMCTR(idx)  (0xfc100000 + (sizeof(u32) * idx))

#define CCBR_CIT_MASK   (0x7ff << 6)
#define CCBR_DUC        (1 << 3)
#define CCBR_CMDS       (1 << 1)
#define CCBR_PPCE       (1 << 0)

#ifdef CONFIG_CPU_SHX3
/*
 * The PMCAT location for SH-X3 CPUs was quietly moved, while the CCBR
 * and PMCTR locations remains tentatively constant. This change remains
 * wholly undocumented, and was simply found through trial and error.
 *
 * Early cuts of SH-X3 still appear to use the SH-X/SH-X2 locations, and
 * it's unclear when this ceased to be the case. For now we always use
 * the new location (if future parts keep up with this trend then
 * scanning for them at runtime also remains a viable option.)
 *
 * The gap in the register space also suggests that there are other
 * undocumented counters, so this will need to be revisited at a later
 * point in time.
 */
#define PPC_PMCAT       0xfc100240
#else
#define PPC_PMCAT       0xfc100080
#endif

#define PMCAT_OVF3      (1 << 27)
#define PMCAT_CNN3      (1 << 26)
#define PMCAT_CLR3      (1 << 25)
#define PMCAT_OVF2      (1 << 19)
#define PMCAT_CLR2      (1 << 17)
#define PMCAT_OVF1      (1 << 11)
#define PMCAT_CNN1      (1 << 10)
#define PMCAT_CLR1      (1 << 9)
#define PMCAT_OVF0      (1 << 3)
#define PMCAT_CLR0      (1 << 1)

static struct sh_pmu sh4a_pmu;

/*
 * Supported raw event codes:
 *
 *      Event Code      Description
 *      ----------      -----------
 *
 *      0x0000          number of elapsed cycles
 *      0x0200          number of elapsed cycles in privileged mode
 *      0x0280          number of elapsed cycles while SR.BL is asserted
 *      0x0202          instruction execution
 *      0x0203          instruction execution in parallel
 *      0x0204          number of unconditional branches
 *      0x0208          number of exceptions
 *      0x0209          number of interrupts
 *      0x0220          UTLB miss caused by instruction fetch
 *      0x0222          UTLB miss caused by operand access
 *      0x02a0          number of ITLB misses
 *      0x0028          number of accesses to instruction memories
 *      0x0029          number of accesses to instruction cache
 *      0x002a          instruction cache miss
 *      0x022e          number of access to instruction X/Y memory
 *      0x0030          number of reads to operand memories
 *      0x0038          number of writes to operand memories
 *      0x0031          number of operand cache read accesses
 *      0x0039          number of operand cache write accesses
 *      0x0032          operand cache read miss
 *      0x003a          operand cache write miss
 *      0x0236          number of reads to operand X/Y memory
 *      0x023e          number of writes to operand X/Y memory
 *      0x0237          number of reads to operand U memory
 *      0x023f          number of writes to operand U memory
 *      0x0337          number of U memory read buffer misses
 *      0x02b4          number of wait cycles due to operand read access
 *      0x02bc          number of wait cycles due to operand write access
 *      0x0033          number of wait cycles due to operand cache read miss
 *      0x003b          number of wait cycles due to operand cache write miss
 */

/*
 * Special reserved bits used by hardware emulators, read values will
 * vary, but writes must always be 0.
 */
#define PMCAT_EMU_CLR_MASK      ((1 << 24) | (1 << 16) | (1 << 8) | (1 << 0))

static const int sh4a_general_events[] = {
        [PERF_COUNT_HW_CPU_CYCLES]              = 0x0000,
        [PERF_COUNT_HW_INSTRUCTIONS]            = 0x0202,
        [PERF_COUNT_HW_CACHE_REFERENCES]        = 0x0029,       /* I-cache */
        [PERF_COUNT_HW_CACHE_MISSES]            = 0x002a,       /* I-cache */
        [PERF_COUNT_HW_BRANCH_INSTRUCTIONS]     = 0x0204,
        [PERF_COUNT_HW_BRANCH_MISSES]           = -1,
        [PERF_COUNT_HW_BUS_CYCLES]              = -1,
};

#define C(x)    PERF_COUNT_HW_CACHE_##x

static const int sh4a_cache_events
                        [PERF_COUNT_HW_CACHE_MAX]
                        [PERF_COUNT_HW_CACHE_OP_MAX]
                        [PERF_COUNT_HW_CACHE_RESULT_MAX] =
{
        [ C(L1D) ] = {
                [ C(OP_READ) ] = {
                        [ C(RESULT_ACCESS) ] = 0x0031,
                        [ C(RESULT_MISS)   ] = 0x0032,
                },
                [ C(OP_WRITE) ] = {
                        [ C(RESULT_ACCESS) ] = 0x0039,
                        [ C(RESULT_MISS)   ] = 0x003a,
                },
                [ C(OP_PREFETCH) ] = {
                        [ C(RESULT_ACCESS) ] = 0,
                        [ C(RESULT_MISS)   ] = 0,
                },
        },

        [ C(L1I) ] = {
                [ C(OP_READ) ] = {
                        [ C(RESULT_ACCESS) ] = 0x0029,
                        [ C(RESULT_MISS)   ] = 0x002a,
                },
                [ C(OP_WRITE) ] = {
                        [ C(RESULT_ACCESS) ] = -1,
                        [ C(RESULT_MISS)   ] = -1,
                },
                [ C(OP_PREFETCH) ] = {
                        [ C(RESULT_ACCESS) ] = 0,
                        [ C(RESULT_MISS)   ] = 0,
                },
        },

        [ C(LL) ] = {
                [ C(OP_READ) ] = {
                        [ C(RESULT_ACCESS) ] = 0x0030,
                        [ C(RESULT_MISS)   ] = 0,
                },
                [ C(OP_WRITE) ] = {
                        [ C(RESULT_ACCESS) ] = 0x0038,
                        [ C(RESULT_MISS)   ] = 0,
                },
                [ C(OP_PREFETCH) ] = {
                        [ C(RESULT_ACCESS) ] = 0,
                        [ C(RESULT_MISS)   ] = 0,
                },
        },

        [ C(DTLB) ] = {
                [ C(OP_READ) ] = {
                        [ C(RESULT_ACCESS) ] = 0x0222,
                        [ C(RESULT_MISS)   ] = 0x0220,
                },
                [ C(OP_WRITE) ] = {
                        [ C(RESULT_ACCESS) ] = 0,
                        [ C(RESULT_MISS)   ] = 0,
                },
                [ C(OP_PREFETCH) ] = {
                        [ C(RESULT_ACCESS) ] = 0,
                        [ C(RESULT_MISS)   ] = 0,
                },
        },

        [ C(ITLB) ] = {
                [ C(OP_READ) ] = {
                        [ C(RESULT_ACCESS) ] = 0,
                        [ C(RESULT_MISS)   ] = 0x02a0,
                },
                [ C(OP_WRITE) ] = {
                        [ C(RESULT_ACCESS) ] = -1,
                        [ C(RESULT_MISS)   ] = -1,
                },
                [ C(OP_PREFETCH) ] = {
                        [ C(RESULT_ACCESS) ] = -1,
                        [ C(RESULT_MISS)   ] = -1,
                },
        },

        [ C(BPU) ] = {
                [ C(OP_READ) ] = {
                        [ C(RESULT_ACCESS) ] = -1,
                        [ C(RESULT_MISS)   ] = -1,
                },
                [ C(OP_WRITE) ] = {
                        [ C(RESULT_ACCESS) ] = -1,
                        [ C(RESULT_MISS)   ] = -1,
                },
                [ C(OP_PREFETCH) ] = {
                        [ C(RESULT_ACCESS) ] = -1,
                        [ C(RESULT_MISS)   ] = -1,
                },
        },

        [ C(NODE) ] = {
                [ C(OP_READ) ] = {
                        [ C(RESULT_ACCESS) ] = -1,
                        [ C(RESULT_MISS)   ] = -1,
                },
                [ C(OP_WRITE) ] = {
                        [ C(RESULT_ACCESS) ] = -1,
                        [ C(RESULT_MISS)   ] = -1,
                },
                [ C(OP_PREFETCH) ] = {
                        [ C(RESULT_ACCESS) ] = -1,
                        [ C(RESULT_MISS)   ] = -1,
                },
        },
};

static int sh4a_event_map(int event)
{
        return sh4a_general_events[event];
}

static u64 sh4a_pmu_read(int idx)
{
        return __raw_readl(PPC_PMCTR(idx));
}

static void sh4a_pmu_disable(struct hw_perf_event *hwc, int idx)
{
        unsigned int tmp;

        tmp = __raw_readl(PPC_CCBR(idx));
        tmp &= ~(CCBR_CIT_MASK | CCBR_DUC);
        __raw_writel(tmp, PPC_CCBR(idx));
}

static void sh4a_pmu_enable(struct hw_perf_event *hwc, int idx)
{
        unsigned int tmp;

        tmp = __raw_readl(PPC_PMCAT);
        tmp &= ~PMCAT_EMU_CLR_MASK;
        tmp |= idx ? PMCAT_CLR1 : PMCAT_CLR0;
        __raw_writel(tmp, PPC_PMCAT);

        tmp = __raw_readl(PPC_CCBR(idx));
        tmp |= (hwc->config << 6) | CCBR_CMDS | CCBR_PPCE;
        __raw_writel(tmp, PPC_CCBR(idx));

        __raw_writel(__raw_readl(PPC_CCBR(idx)) | CCBR_DUC, PPC_CCBR(idx));
}

static void sh4a_pmu_disable_all(void)
{
        int i;

        for (i = 0; i < sh4a_pmu.num_events; i++)
                __raw_writel(__raw_readl(PPC_CCBR(i)) & ~CCBR_DUC, PPC_CCBR(i));
}

static void sh4a_pmu_enable_all(void)
{
        int i;

        for (i = 0; i < sh4a_pmu.num_events; i++)
                __raw_writel(__raw_readl(PPC_CCBR(i)) | CCBR_DUC, PPC_CCBR(i));
}

static struct sh_pmu sh4a_pmu = {
        .name           = "sh4a",
        .num_events     = 2,
        .event_map      = sh4a_event_map,
        .max_events     = ARRAY_SIZE(sh4a_general_events),
        .raw_event_mask = 0x3ff,
        .cache_events   = &sh4a_cache_events,
        .read           = sh4a_pmu_read,
        .disable        = sh4a_pmu_disable,
        .enable         = sh4a_pmu_enable,
        .disable_all    = sh4a_pmu_disable_all,
        .enable_all     = sh4a_pmu_enable_all,
};

static int __init sh4a_pmu_init(void)
{
        /*
         * Make sure this CPU actually has perf counters.
         */
        if (!(boot_cpu_data.flags & CPU_HAS_PERF_COUNTER)) {
                pr_notice("HW perf events unsupported, software events only.\n");
                return -ENODEV;
        }

        return register_sh_pmu(&sh4a_pmu);
}
early_initcall(sh4a_pmu_init);