/*
 * QTests for Nuvoton NPCM7xx PWM Modules.
 *
 * Copyright 2020 Google LLC
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by the
 * Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
 * for more details.
 */

#include "qemu/osdep.h"
#include "qemu/bitops.h"
#include "libqos/libqtest.h"
#include "qapi/qmp/qdict.h"
#include "qapi/qmp/qnum.h"

#define REF_HZ          25000000

/* Register field definitions. */
#define CH_EN           BIT(0)
#define CH_INV          BIT(2)
#define CH_MOD          BIT(3)

/* Registers shared between all PWMs in a module */
#define PPR             0x00
#define CSR             0x04
#define PCR             0x08
#define PIER            0x3c
#define PIIR            0x40

/* CLK module related */
#define CLK_BA          0xf0801000
#define CLKSEL          0x04
#define CLKDIV1         0x08
#define CLKDIV2         0x2c
#define PLLCON0         0x0c
#define PLLCON1         0x10
#define PLL_INDV(rv)    extract32((rv), 0, 6)
#define PLL_FBDV(rv)    extract32((rv), 16, 12)
#define PLL_OTDV1(rv)   extract32((rv), 8, 3)
#define PLL_OTDV2(rv)   extract32((rv), 13, 3)
#define APB3CKDIV(rv)   extract32((rv), 28, 2)
#define CLK2CKDIV(rv)   extract32((rv), 0, 1)
#define CLK4CKDIV(rv)   extract32((rv), 26, 2)
#define CPUCKSEL(rv)    extract32((rv), 0, 2)

#define MAX_DUTY        1000000

typedef struct PWMModule {
    int irq;
    uint64_t base_addr;
} PWMModule;

typedef struct PWM {
    uint32_t cnr_offset;
    uint32_t cmr_offset;
    uint32_t pdr_offset;
    uint32_t pwdr_offset;
} PWM;

typedef struct TestData {
    const PWMModule *module;
    const PWM *pwm;
} TestData;

static const PWMModule pwm_module_list[] = {
    {
        .irq        = 93,
        .base_addr  = 0xf0103000
    },
    {
        .irq        = 94,
        .base_addr  = 0xf0104000
    }
};

static const PWM pwm_list[] = {
    {
        .cnr_offset     = 0x0c,
        .cmr_offset     = 0x10,
        .pdr_offset     = 0x14,
        .pwdr_offset    = 0x44,
    },
    {
        .cnr_offset     = 0x18,
        .cmr_offset     = 0x1c,
        .pdr_offset     = 0x20,
        .pwdr_offset    = 0x48,
    },
    {
        .cnr_offset     = 0x24,
        .cmr_offset     = 0x28,
        .pdr_offset     = 0x2c,
        .pwdr_offset    = 0x4c,
    },
    {
        .cnr_offset     = 0x30,
        .cmr_offset     = 0x34,
        .pdr_offset     = 0x38,
        .pwdr_offset    = 0x50,
    },
};

static const int ppr_base[] = { 0, 0, 8, 8 };
static const int csr_base[] = { 0, 4, 8, 12 };
static const int pcr_base[] = { 0, 8, 12, 16 };

static const uint32_t ppr_list[] = {
    0,
    1,
    10,
    100,
    255, /* Max possible value. */
};

static const uint32_t csr_list[] = {
    0,
    1,
    2,
    3,
    4, /* Max possible value. */
};

static const uint32_t cnr_list[] = {
    0,
    1,
    50,
    100,
    150,
    200,
    1000,
    10000,
    65535, /* Max possible value. */
};

static const uint32_t cmr_list[] = {
    0,
    1,
    10,
    50,
    100,
    150,
    200,
    1000,
    10000,
    65535, /* Max possible value. */
};

/* Returns the index of the PWM module. */
static int pwm_module_index(const PWMModule *module)
{
    ptrdiff_t diff = module - pwm_module_list;

    g_assert_true(diff >= 0 && diff < ARRAY_SIZE(pwm_module_list));

    return diff;
}

/* Returns the index of the PWM entry. */
static int pwm_index(const PWM *pwm)
{
    ptrdiff_t diff = pwm - pwm_list;

    g_assert_true(diff >= 0 && diff < ARRAY_SIZE(pwm_list));

    return diff;
}

static uint64_t pwm_qom_get(QTestState *qts, const char *path, const char *name)
{
    QDict *response;

    g_test_message("Getting properties %s from %s", name, path);
    response = qtest_qmp(qts, "{ 'execute': 'qom-get',"
            " 'arguments': { 'path': %s, 'property': %s}}",
            path, name);
    /* The qom set message returns successfully. */
    g_assert_true(qdict_haskey(response, "return"));
    return qnum_get_uint(qobject_to(QNum, qdict_get(response, "return")));
}

static uint64_t pwm_get_freq(QTestState *qts, int module_index, int pwm_index)
{
    char path[100];
    char name[100];

    sprintf(path, "/machine/soc/pwm[%d]", module_index);
    sprintf(name, "freq[%d]", pwm_index);

    return pwm_qom_get(qts, path, name);
}

static uint64_t pwm_get_duty(QTestState *qts, int module_index, int pwm_index)
{
    char path[100];
    char name[100];

    sprintf(path, "/machine/soc/pwm[%d]", module_index);
    sprintf(name, "duty[%d]", pwm_index);

    return pwm_qom_get(qts, path, name);
}

static uint32_t get_pll(uint32_t con)
{
    return REF_HZ * PLL_FBDV(con) / (PLL_INDV(con) * PLL_OTDV1(con)
            * PLL_OTDV2(con));
}

static uint64_t read_pclk(QTestState *qts)
{
    uint64_t freq = REF_HZ;
    uint32_t clksel = qtest_readl(qts, CLK_BA + CLKSEL);
    uint32_t pllcon;
    uint32_t clkdiv1 = qtest_readl(qts, CLK_BA + CLKDIV1);
    uint32_t clkdiv2 = qtest_readl(qts, CLK_BA + CLKDIV2);

    switch (CPUCKSEL(clksel)) {
    case 0:
        pllcon = qtest_readl(qts, CLK_BA + PLLCON0);
        freq = get_pll(pllcon);
        break;
    case 1:
        pllcon = qtest_readl(qts, CLK_BA + PLLCON1);
        freq = get_pll(pllcon);
        break;
    case 2:
        break;
    case 3:
        break;
    default:
        g_assert_not_reached();
    }

    freq >>= (CLK2CKDIV(clkdiv1) + CLK4CKDIV(clkdiv1) + APB3CKDIV(clkdiv2));

    return freq;
}

static uint32_t pwm_selector(uint32_t csr)
{
    switch (csr) {
    case 0:
        return 2;
    case 1:
        return 4;
    case 2:
        return 8;
    case 3:
        return 16;
    case 4:
        return 1;
    default:
        g_assert_not_reached();
    }
}

static uint64_t pwm_compute_freq(QTestState *qts, uint32_t ppr, uint32_t csr,
        uint32_t cnr)
{
    return read_pclk(qts) / ((ppr + 1) * pwm_selector(csr) * (cnr + 1));
}

static uint64_t pwm_compute_duty(uint32_t cnr, uint32_t cmr, bool inverted)
{
    uint64_t duty;

    if (cnr == 0) {
        /* PWM is stopped. */
        duty = 0;
    } else if (cmr >= cnr) {
        duty = MAX_DUTY;
    } else {
        duty = MAX_DUTY * (cmr + 1) / (cnr + 1);
    }

    if (inverted) {
        duty = MAX_DUTY - duty;
    }

    return duty;
}

static uint32_t pwm_read(QTestState *qts, const TestData *td, unsigned offset)
{
    return qtest_readl(qts, td->module->base_addr + offset);
}

static void pwm_write(QTestState *qts, const TestData *td, unsigned offset,
        uint32_t value)
{
    qtest_writel(qts, td->module->base_addr + offset, value);
}

static uint32_t pwm_read_ppr(QTestState *qts, const TestData *td)
{
    return extract32(pwm_read(qts, td, PPR), ppr_base[pwm_index(td->pwm)], 8);
}

static void pwm_write_ppr(QTestState *qts, const TestData *td, uint32_t value)
{
    pwm_write(qts, td, PPR, value << ppr_base[pwm_index(td->pwm)]);
}

static uint32_t pwm_read_csr(QTestState *qts, const TestData *td)
{
    return extract32(pwm_read(qts, td, CSR), csr_base[pwm_index(td->pwm)], 3);
}

static void pwm_write_csr(QTestState *qts, const TestData *td, uint32_t value)
{
    pwm_write(qts, td, CSR, value << csr_base[pwm_index(td->pwm)]);
}

static uint32_t pwm_read_pcr(QTestState *qts, const TestData *td)
{
    return extract32(pwm_read(qts, td, PCR), pcr_base[pwm_index(td->pwm)], 4);
}

static void pwm_write_pcr(QTestState *qts, const TestData *td, uint32_t value)
{
    pwm_write(qts, td, PCR, value << pcr_base[pwm_index(td->pwm)]);
}

static uint32_t pwm_read_cnr(QTestState *qts, const TestData *td)
{
    return pwm_read(qts, td, td->pwm->cnr_offset);
}

static void pwm_write_cnr(QTestState *qts, const TestData *td, uint32_t value)
{
    pwm_write(qts, td, td->pwm->cnr_offset, value);
}

static uint32_t pwm_read_cmr(QTestState *qts, const TestData *td)
{
    return pwm_read(qts, td, td->pwm->cmr_offset);
}

static void pwm_write_cmr(QTestState *qts, const TestData *td, uint32_t value)
{
    pwm_write(qts, td, td->pwm->cmr_offset, value);
}

/* Check pwm registers can be reset to default value */
static void test_init(gconstpointer test_data)
{
    const TestData *td = test_data;
    QTestState *qts = qtest_init("-machine quanta-gsj");
    int module = pwm_module_index(td->module);
    int pwm = pwm_index(td->pwm);

    g_assert_cmpuint(pwm_get_freq(qts, module, pwm), ==, 0);
    g_assert_cmpuint(pwm_get_duty(qts, module, pwm), ==, 0);

    qtest_quit(qts);
}

/* One-shot mode should not change frequency and duty cycle. */
static void test_oneshot(gconstpointer test_data)
{
    const TestData *td = test_data;
    QTestState *qts = qtest_init("-machine quanta-gsj");
    int module = pwm_module_index(td->module);
    int pwm = pwm_index(td->pwm);
    uint32_t ppr, csr, pcr;
    int i, j;

    pcr = CH_EN;
    for (i = 0; i < ARRAY_SIZE(ppr_list); ++i) {
        ppr = ppr_list[i];
        pwm_write_ppr(qts, td, ppr);

        for (j = 0; j < ARRAY_SIZE(csr_list); ++j) {
            csr = csr_list[j];
            pwm_write_csr(qts, td, csr);
            pwm_write_pcr(qts, td, pcr);

            g_assert_cmpuint(pwm_read_ppr(qts, td), ==, ppr);
            g_assert_cmpuint(pwm_read_csr(qts, td), ==, csr);
            g_assert_cmpuint(pwm_read_pcr(qts, td), ==, pcr);
            g_assert_cmpuint(pwm_get_freq(qts, module, pwm), ==, 0);
            g_assert_cmpuint(pwm_get_duty(qts, module, pwm), ==, 0);
        }
    }

    qtest_quit(qts);
}

/* In toggle mode, the PWM generates correct outputs. */
static void test_toggle(gconstpointer test_data)
{
    const TestData *td = test_data;
    QTestState *qts = qtest_init("-machine quanta-gsj");
    int module = pwm_module_index(td->module);
    int pwm = pwm_index(td->pwm);
    uint32_t ppr, csr, pcr, cnr, cmr;
    int i, j, k, l;
    uint64_t expected_freq, expected_duty;

    pcr = CH_EN | CH_MOD;
    for (i = 0; i < ARRAY_SIZE(ppr_list); ++i) {
        ppr = ppr_list[i];
        pwm_write_ppr(qts, td, ppr);

        for (j = 0; j < ARRAY_SIZE(csr_list); ++j) {
            csr = csr_list[j];
            pwm_write_csr(qts, td, csr);

            for (k = 0; k < ARRAY_SIZE(cnr_list); ++k) {
                cnr = cnr_list[k];
                pwm_write_cnr(qts, td, cnr);

                for (l = 0; l < ARRAY_SIZE(cmr_list); ++l) {
                    cmr = cmr_list[l];
                    pwm_write_cmr(qts, td, cmr);
                    expected_freq = pwm_compute_freq(qts, ppr, csr, cnr);
                    expected_duty = pwm_compute_duty(cnr, cmr, false);

                    pwm_write_pcr(qts, td, pcr);
                    g_assert_cmpuint(pwm_read_ppr(qts, td), ==, ppr);
                    g_assert_cmpuint(pwm_read_csr(qts, td), ==, csr);
                    g_assert_cmpuint(pwm_read_pcr(qts, td), ==, pcr);
                    g_assert_cmpuint(pwm_read_cnr(qts, td), ==, cnr);
                    g_assert_cmpuint(pwm_read_cmr(qts, td), ==, cmr);
                    g_assert_cmpuint(pwm_get_duty(qts, module, pwm),
                            ==, expected_duty);
                    if (expected_duty != 0 && expected_duty != 100) {
                        /* Duty cycle with 0 or 100 doesn't need frequency. */
                        g_assert_cmpuint(pwm_get_freq(qts, module, pwm),
                                ==, expected_freq);
                    }

                    /* Test inverted mode */
                    expected_duty = pwm_compute_duty(cnr, cmr, true);
                    pwm_write_pcr(qts, td, pcr | CH_INV);
                    g_assert_cmpuint(pwm_read_pcr(qts, td), ==, pcr | CH_INV);
                    g_assert_cmpuint(pwm_get_duty(qts, module, pwm),
                            ==, expected_duty);
                    if (expected_duty != 0 && expected_duty != 100) {
                        /* Duty cycle with 0 or 100 doesn't need frequency. */
                        g_assert_cmpuint(pwm_get_freq(qts, module, pwm),
                                ==, expected_freq);
                    }

                }
            }
        }
    }

    qtest_quit(qts);
}

static void pwm_add_test(const char *name, const TestData* td,
        GTestDataFunc fn)
{
    g_autofree char *full_name = g_strdup_printf(
            "npcm7xx_pwm/module[%d]/pwm[%d]/%s", pwm_module_index(td->module),
            pwm_index(td->pwm), name);
    qtest_add_data_func(full_name, td, fn);
}
#define add_test(name, td) pwm_add_test(#name, td, test_##name)

int main(int argc, char **argv)
{
    TestData test_data_list[ARRAY_SIZE(pwm_module_list) * ARRAY_SIZE(pwm_list)];

    g_test_init(&argc, &argv, NULL);

    for (int i = 0; i < ARRAY_SIZE(pwm_module_list); ++i) {
        for (int j = 0; j < ARRAY_SIZE(pwm_list); ++j) {
            TestData *td = &test_data_list[i * ARRAY_SIZE(pwm_list) + j];

            td->module = &pwm_module_list[i];
            td->pwm = &pwm_list[j];

            add_test(init, td);
            add_test(oneshot, td);
            add_test(toggle, td);
        }
    }

    return g_test_run();
}