/* SPDX-License-Identifier: MIT */

#include "kboot.h"
#include "adt.h"
#include "assert.h"
#include "soc.h"
#include "utils.h"

#include "libfdt/libfdt.h"

#define bail(...)                                                                                  \
    do {                                                                                           \
        printf(__VA_ARGS__);                                                                       \
        return -1;                                                                                 \
    } while (0)

#define MAX_PSTATES  16
#define MAX_CLUSTERS 8

struct perf_state {
    u32 freq;
    u32 volt;
};

u32 t8103_pwr_scale[] = {0, 63, 80, 108, 150, 198, 210};

int calc_power_t8103(int sgx, u32 count, u32 table_count, const struct perf_state *perf_states,
                     u32 *max_pwr)
{
    UNUSED(sgx);

    u32 pwr_scale_count = ARRAY_SIZE(t8103_pwr_scale);

    if (table_count != 1)
        bail("ADT: GPU: expected 1 perf state table but got %d\n", table_count);

    if (count != pwr_scale_count)
        bail("ADT: GPU: expected %d perf states but got %d\n", pwr_scale_count, count);

    for (u32 i = 0; i < pwr_scale_count; i++)
        max_pwr[i] = (u32)perf_states[i].volt * (u32)t8103_pwr_scale[i] * 100;

    return 0;
}

u32 t6000_pwr_scale[] = {0, 15, 19, 25, 34, 50, 100};

int calc_power_t600x(int sgx, u32 count, u32 table_count, const struct perf_state *perf_states,
                     u32 *max_pwr)
{
    UNUSED(sgx);
    UNUSED(perf_states);

    u32 nclusters = 0;
    switch (chip_id) {
        case T6000:
            nclusters = 2;
            break;
        case T6001:
            nclusters = 4;
            break;
        case T6002:
            nclusters = 8;
            break;
    }

    u32 pwr_scale_count = ARRAY_SIZE(t6000_pwr_scale);

    if (table_count != nclusters)
        bail("ADT: GPU: expected %d perf state tables but got %d\n", nclusters, table_count);

    if (count != pwr_scale_count)
        bail("ADT: GPU: expected %d perf states but got %d\n", pwr_scale_count, count);

    for (u32 i = 0; i < pwr_scale_count; i++) {
        max_pwr[i] = t6000_pwr_scale[i] * 1667430 * nclusters / 8;
    }

    return 0;
}

static int dt_set_region(void *dt, int sgx, const char *name, const char *path)
{
    u64 base, size;
    char prop[64];

    snprintf(prop, sizeof(prop), "%s-base", name);
    if (ADT_GETPROP(adt, sgx, prop, &base) < 0 || !base)
        bail("ADT: GPU: failed to find %s property\n", prop);

    snprintf(prop, sizeof(prop), "%s-size", name);
    if (ADT_GETPROP(adt, sgx, prop, &size) < 0 || !base)
        bail("ADT: GPU: failed to find %s property\n", prop);

    int node = fdt_path_offset(dt, path);
    if (node < 0)
        bail("FDT: GPU: failed to find %s node\n", path);

    fdt64_t reg[2];

    fdt64_st(&reg[0], base);
    fdt64_st(&reg[1], size);

    if (fdt_setprop_inplace(dt, node, "reg", reg, sizeof(reg)))
        bail("FDT: GPU: failed to set reg prop for %s\n", path);

    return 0;
}

int dt_set_gpu(void *dt)
{
    int (*calc_power)(int sgx, u32 count, u32 table_count, const struct perf_state *perf,
                      u32 *max_pwr);

    switch (chip_id) {
        case T8103:
            calc_power = calc_power_t8103;
            break;
        case T6000:
        case T6001:
        case T6002:
            calc_power = calc_power_t600x;
            break;
        default:
            printf("ADT: GPU: unsupported chip!\n");
            return 0;
    }

    int gpu = fdt_path_offset(dt, "gpu");
    if (gpu < 0) {
        printf("FDT: GPU: gpu alias not found in device tree\n");
        return 0;
    }

    int len;
    const fdt32_t *opps_ph = fdt_getprop(dt, gpu, "operating-points-v2", &len);
    if (!opps_ph || len != 4)
        bail("FDT: GPU: operating-points-v2 not found\n");

    int opps = fdt_node_offset_by_phandle(dt, fdt32_ld(opps_ph));
    if (opps < 0)
        bail("FDT: GPU: node for phandle %u not found\n", fdt32_ld(opps_ph));

    int sgx = adt_path_offset(adt, "/arm-io/sgx");
    if (sgx < 0)
        bail("ADT: GPU: /arm-io/sgx node not found\n");

    u32 perf_state_count;
    if (ADT_GETPROP(adt, sgx, "perf-state-count", &perf_state_count) < 0 || !perf_state_count)
        bail("ADT: GPU: missing perf-state-count\n");

    u32 perf_state_table_count;
    if (ADT_GETPROP(adt, sgx, "perf-state-table-count", &perf_state_table_count) < 0 ||
        !perf_state_table_count)
        bail("ADT: GPU: missing perf-state-table-count\n");

    if (perf_state_count > MAX_PSTATES)
        bail("ADT: GPU: perf-state-count too large\n");

    if (perf_state_table_count > MAX_CLUSTERS)
        bail("ADT: GPU: perf-state-table-count too large\n");

    u32 perf_states_len;
    const struct perf_state *perf_states;

    perf_states = adt_getprop(adt, sgx, "perf-states", &perf_states_len);
    if (!perf_states ||
        perf_states_len != sizeof(*perf_states) * perf_state_count * perf_state_table_count)
        bail("ADT: GPU: invalid perf-states length\n");

    u32 max_pwr[MAX_PSTATES];

    if (calc_power(sgx, perf_state_count, perf_state_table_count, perf_states, max_pwr))
        return -1;

    u32 i = 0;
    int opp;
    fdt_for_each_subnode(opp, dt, opps)
    {
        fdt32_t volts[MAX_CLUSTERS];

        for (u32 j = 0; j < perf_state_table_count; j++) {
            volts[j] = cpu_to_fdt32(perf_states[i + j * perf_state_count].volt * 1000);
        }

        if (i >= perf_state_count)
            bail("FDT: GPU: Expected %d operating points, but found more\n", perf_state_count);

        if (fdt_setprop_inplace(dt, opp, "opp-microvolt", &volts,
                                sizeof(u32) * perf_state_table_count))
            bail("FDT: GPU: Failed to set opp-microvolt for PS %d\n", i);

        if (fdt_setprop_inplace_u64(dt, opp, "opp-hz", perf_states[i].freq))
            bail("FDT: GPU: Failed to set opp-hz for PS %d\n", i);

        if (fdt_setprop_inplace_u32(dt, opp, "opp-microwatt", max_pwr[i]))
            bail("FDT: GPU: Failed to set opp-microwatt for PS %d\n", i);

        i++;
    }

    if (i != perf_state_count)
        bail("FDT: GPU: Expected %d operating points, but found %d\n", perf_state_count, i);

    if (dt_set_region(dt, sgx, "gfx-handoff", "/reserved-memory/uat-handoff"))
        return -1;
    if (dt_set_region(dt, sgx, "gfx-shared-region", "/reserved-memory/uat-pagetables"))
        return -1;
    if (dt_set_region(dt, sgx, "gpu-region", "/reserved-memory/uat-ttbs"))
        return -1;

    return 0;
}