// SPDX-License-Identifier: GPL-2.0+
/* Copyright (C) 2026 Raspberry Pi */

#include <linux/clk.h>

#include <drm/drm_print.h>

#include "v3d_drv.h"
#include "v3d_regs.h"

static int
v3d_resume_sms(struct v3d_dev *v3d)
{
        if (v3d->ver < V3D_GEN_71)
                return 0;

        V3D_SMS_WRITE(V3D_SMS_TEE_CS, V3D_SMS_CLEAR_POWER_OFF);

        if (wait_for((V3D_GET_FIELD(V3D_SMS_READ(V3D_SMS_TEE_CS),
                                    V3D_SMS_STATE) == V3D_SMS_IDLE), 100)) {
                drm_err(&v3d->drm, "Failed to power up SMS\n");
                return -ETIMEDOUT;
        }

        v3d_reset_sms(v3d);

        return 0;
}

static int
v3d_suspend_sms(struct v3d_dev *v3d)
{
        if (v3d->ver < V3D_GEN_71)
                return 0;

        V3D_SMS_WRITE(V3D_SMS_TEE_CS, V3D_SMS_POWER_OFF);

        if (wait_for((V3D_GET_FIELD(V3D_SMS_READ(V3D_SMS_TEE_CS),
                                    V3D_SMS_STATE) == V3D_SMS_POWER_OFF_STATE), 100)) {
                drm_err(&v3d->drm, "Failed to power off SMS\n");
                return -ETIMEDOUT;
        }

        return 0;
}

int v3d_power_suspend(struct device *dev)
{
        struct drm_device *drm = dev_get_drvdata(dev);
        struct v3d_dev *v3d = to_v3d_dev(drm);
        int ret;

        v3d_irq_disable(v3d);

        v3d_clean_caches(v3d);

        /* Wait until V3D has no active or pending AXI transactions. */
        v3d_idle_axi(v3d, 0);
        v3d_idle_gca(v3d);

        ret = v3d_suspend_sms(v3d);
        if (ret) {
                /* Staying active: undo the GMP STOP_REQ from v3d_idle_axi(). */
                V3D_WRITE(V3D_GMP_CFG(v3d->ver),
                          V3D_READ(V3D_GMP_CFG(v3d->ver)) & ~V3D_GMP_CFG_STOP_REQ);
                v3d_irq_enable(v3d);
                return ret;
        }

        clk_disable_unprepare(v3d->clk);

        return 0;
}

int v3d_power_resume(struct device *dev)
{
        struct drm_device *drm = dev_get_drvdata(dev);
        struct v3d_dev *v3d = to_v3d_dev(drm);
        int ret;

        ret = clk_prepare_enable(v3d->clk);
        if (ret)
                return ret;

        ret = v3d_resume_sms(v3d);
        if (ret) {
                clk_disable_unprepare(v3d->clk);
                return ret;
        }

        v3d_init_hw_state(v3d);
        v3d_mmu_set_page_table(v3d);
        v3d_irq_enable(v3d);

        return 0;
}