drm/msm: carve out KMS code from msm_drv.c

The msm_drv.c contains generic code intermixed with KMS handling code.
Move all KMS-related code to a separate msm_kms.c file, cleaning up init
code while doing this move. This also prevents msm driver from registering
modesetting / atomic interfaces in the headless case.
Reviewed-by: Rob Clark <robdclark@gmail.com>
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Patchwork: https://patchwork.freedesktop.org/patch/561648/Signed-off-by: Rob Clark <robdclark@chromium.org>

drivers/gpu/drm/msm/Makefile

@@ -106,6 +106,7 @@ msm-y += \
 	msm_gpu_devfreq.o \
 	msm_io_utils.o \
 	msm_iommu.o \
+	msm_kms.o \
 	msm_perf.o \
 	msm_rd.o \
 	msm_ringbuffer.o \

drivers/gpu/drm/msm/msm_kms.c

+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2016-2018, 2020-2021 The Linux Foundation. All rights reserved.
+ * Copyright (C) 2013 Red Hat
+ * Author: Rob Clark <robdclark@gmail.com>
+ */
+
+#include <linux/kthread.h>
+#include <linux/sched/mm.h>
+#include <uapi/linux/sched/types.h>
+
+#include <drm/drm_aperture.h>
+#include <drm/drm_drv.h>
+#include <drm/drm_mode_config.h>
+#include <drm/drm_vblank.h>
+
+#include "disp/msm_disp_snapshot.h"
+#include "msm_drv.h"
+#include "msm_gem.h"
+#include "msm_kms.h"
+#include "msm_mmu.h"
+
+static const struct drm_mode_config_funcs mode_config_funcs = {
+	.fb_create = msm_framebuffer_create,
+	.atomic_check = msm_atomic_check,
+	.atomic_commit = drm_atomic_helper_commit,
+};
+
+static const struct drm_mode_config_helper_funcs mode_config_helper_funcs = {
+	.atomic_commit_tail = msm_atomic_commit_tail,
+};
+
+static irqreturn_t msm_irq(int irq, void *arg)
+{
+	struct drm_device *dev = arg;
+	struct msm_drm_private *priv = dev->dev_private;
+	struct msm_kms *kms = priv->kms;
+
+	BUG_ON(!kms);
+
+	return kms->funcs->irq(kms);
+}
+
+static void msm_irq_preinstall(struct drm_device *dev)
+{
+	struct msm_drm_private *priv = dev->dev_private;
+	struct msm_kms *kms = priv->kms;
+
+	BUG_ON(!kms);
+
+	kms->funcs->irq_preinstall(kms);
+}
+
+static int msm_irq_postinstall(struct drm_device *dev)
+{
+	struct msm_drm_private *priv = dev->dev_private;
+	struct msm_kms *kms = priv->kms;
+
+	BUG_ON(!kms);
+
+	if (kms->funcs->irq_postinstall)
+		return kms->funcs->irq_postinstall(kms);
+
+	return 0;
+}
+
+static int msm_irq_install(struct drm_device *dev, unsigned int irq)
+{
+	struct msm_drm_private *priv = dev->dev_private;
+	struct msm_kms *kms = priv->kms;
+	int ret;
+
+	if (irq == IRQ_NOTCONNECTED)
+		return -ENOTCONN;
+
+	msm_irq_preinstall(dev);
+
+	ret = request_irq(irq, msm_irq, 0, dev->driver->name, dev);
+	if (ret)
+		return ret;
+
+	kms->irq_requested = true;
+
+	ret = msm_irq_postinstall(dev);
+	if (ret) {
+		free_irq(irq, dev);
+		return ret;
+	}
+
+	return 0;
+}
+
+static void msm_irq_uninstall(struct drm_device *dev)
+{
+	struct msm_drm_private *priv = dev->dev_private;
+	struct msm_kms *kms = priv->kms;
+
+	kms->funcs->irq_uninstall(kms);
+	if (kms->irq_requested)
+		free_irq(kms->irq, dev);
+}
+
+struct msm_vblank_work {
+	struct work_struct work;
+	struct drm_crtc *crtc;
+	bool enable;
+	struct msm_drm_private *priv;
+};
+
+static void vblank_ctrl_worker(struct work_struct *work)
+{
+	struct msm_vblank_work *vbl_work = container_of(work,
+						struct msm_vblank_work, work);
+	struct msm_drm_private *priv = vbl_work->priv;
+	struct msm_kms *kms = priv->kms;
+
+	if (vbl_work->enable)
+		kms->funcs->enable_vblank(kms, vbl_work->crtc);
+	else
+		kms->funcs->disable_vblank(kms,	vbl_work->crtc);
+
+	kfree(vbl_work);
+}
+
+static int vblank_ctrl_queue_work(struct msm_drm_private *priv,
+				  struct drm_crtc *crtc, bool enable)
+{
+	struct msm_vblank_work *vbl_work;
+
+	vbl_work = kzalloc(sizeof(*vbl_work), GFP_ATOMIC);
+	if (!vbl_work)
+		return -ENOMEM;
+
+	INIT_WORK(&vbl_work->work, vblank_ctrl_worker);
+
+	vbl_work->crtc = crtc;
+	vbl_work->enable = enable;
+	vbl_work->priv = priv;
+
+	queue_work(priv->wq, &vbl_work->work);
+
+	return 0;
+}
+
+int msm_crtc_enable_vblank(struct drm_crtc *crtc)
+{
+	struct drm_device *dev = crtc->dev;
+	struct msm_drm_private *priv = dev->dev_private;
+	struct msm_kms *kms = priv->kms;
+	if (!kms)
+		return -ENXIO;
+	drm_dbg_vbl(dev, "crtc=%u", crtc->base.id);
+	return vblank_ctrl_queue_work(priv, crtc, true);
+}
+
+void msm_crtc_disable_vblank(struct drm_crtc *crtc)
+{
+	struct drm_device *dev = crtc->dev;
+	struct msm_drm_private *priv = dev->dev_private;
+	struct msm_kms *kms = priv->kms;
+	if (!kms)
+		return;
+	drm_dbg_vbl(dev, "crtc=%u", crtc->base.id);
+	vblank_ctrl_queue_work(priv, crtc, false);
+}
+
+struct msm_gem_address_space *msm_kms_init_aspace(struct drm_device *dev)
+{
+	struct msm_gem_address_space *aspace;
+	struct msm_mmu *mmu;
+	struct device *mdp_dev = dev->dev;
+	struct device *mdss_dev = mdp_dev->parent;
+	struct device *iommu_dev;
+
+	/*
+	 * IOMMUs can be a part of MDSS device tree binding, or the
+	 * MDP/DPU device.
+	 */
+	if (device_iommu_mapped(mdp_dev))
+		iommu_dev = mdp_dev;
+	else
+		iommu_dev = mdss_dev;
+
+	mmu = msm_iommu_new(iommu_dev, 0);
+	if (IS_ERR(mmu))
+		return ERR_CAST(mmu);
+
+	if (!mmu) {
+		drm_info(dev, "no IOMMU, fallback to phys contig buffers for scanout\n");
+		return NULL;
+	}
+
+	aspace = msm_gem_address_space_create(mmu, "mdp_kms",
+		0x1000, 0x100000000 - 0x1000);
+	if (IS_ERR(aspace)) {
+		dev_err(mdp_dev, "aspace create, error %pe\n", aspace);
+		mmu->funcs->destroy(mmu);
+	}
+
+	return aspace;
+}
+
+void msm_drm_kms_uninit(struct device *dev)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct msm_drm_private *priv = platform_get_drvdata(pdev);
+	struct drm_device *ddev = priv->dev;
+	struct msm_kms *kms = priv->kms;
+	int i;
+
+	BUG_ON(!kms);
+
+	/* clean up event worker threads */
+	for (i = 0; i < priv->num_crtcs; i++) {
+		if (priv->event_thread[i].worker)
+			kthread_destroy_worker(priv->event_thread[i].worker);
+	}
+
+	drm_kms_helper_poll_fini(ddev);
+
+	msm_disp_snapshot_destroy(ddev);
+
+	pm_runtime_get_sync(dev);
+	msm_irq_uninstall(ddev);
+	pm_runtime_put_sync(dev);
+
+	if (kms && kms->funcs)
+		kms->funcs->destroy(kms);
+}
+
+int msm_drm_kms_init(struct device *dev, const struct drm_driver *drv)
+{
+	struct msm_drm_private *priv = dev_get_drvdata(dev);
+	struct drm_device *ddev = priv->dev;
+	struct msm_kms *kms = priv->kms;
+	struct drm_crtc *crtc;
+	int ret;
+
+	/* the fw fb could be anywhere in memory */
+	ret = drm_aperture_remove_framebuffers(drv);
+	if (ret)
+		return ret;
+
+	ret = priv->kms_init(ddev);
+	if (ret) {
+		DRM_DEV_ERROR(dev, "failed to load kms\n");
+		priv->kms = NULL;
+		return ret;
+	}
+
+	/* Enable normalization of plane zpos */
+	ddev->mode_config.normalize_zpos = true;
+
+	ddev->mode_config.funcs = &mode_config_funcs;
+	ddev->mode_config.helper_private = &mode_config_helper_funcs;
+
+	kms->dev = ddev;
+	ret = kms->funcs->hw_init(kms);
+	if (ret) {
+		DRM_DEV_ERROR(dev, "kms hw init failed: %d\n", ret);
+		goto err_msm_uninit;
+	}
+
+	drm_helper_move_panel_connectors_to_head(ddev);
+
+	drm_for_each_crtc(crtc, ddev) {
+		struct msm_drm_thread *ev_thread;
+
+		/* initialize event thread */
+		ev_thread = &priv->event_thread[drm_crtc_index(crtc)];
+		ev_thread->dev = ddev;
+		ev_thread->worker = kthread_create_worker(0, "crtc_event:%d", crtc->base.id);
+		if (IS_ERR(ev_thread->worker)) {
+			ret = PTR_ERR(ev_thread->worker);
+			DRM_DEV_ERROR(dev, "failed to create crtc_event kthread\n");
+			ev_thread->worker = NULL;
+			goto err_msm_uninit;
+		}
+
+		sched_set_fifo(ev_thread->worker->task);
+	}
+
+	ret = drm_vblank_init(ddev, priv->num_crtcs);
+	if (ret < 0) {
+		DRM_DEV_ERROR(dev, "failed to initialize vblank\n");
+		goto err_msm_uninit;
+	}
+
+	pm_runtime_get_sync(dev);
+	ret = msm_irq_install(ddev, kms->irq);
+	pm_runtime_put_sync(dev);
+	if (ret < 0) {
+		DRM_DEV_ERROR(dev, "failed to install IRQ handler\n");
+		goto err_msm_uninit;
+	}
+
+	ret = msm_disp_snapshot_init(ddev);
+	if (ret)
+		DRM_DEV_ERROR(dev, "msm_disp_snapshot_init failed ret = %d\n", ret);
+
+	drm_mode_config_reset(ddev);
+
+	return 0;
+
+err_msm_uninit:
+	return ret;
+}
+
+int msm_kms_pm_prepare(struct device *dev)
+{
+	struct msm_drm_private *priv = dev_get_drvdata(dev);
+	struct drm_device *ddev = priv ? priv->dev : NULL;
+
+	if (!priv || !priv->kms)
+		return 0;
+
+	return drm_mode_config_helper_suspend(ddev);
+}
+
+void msm_kms_pm_complete(struct device *dev)
+{
+	struct msm_drm_private *priv = dev_get_drvdata(dev);
+	struct drm_device *ddev = priv ? priv->dev : NULL;
+
+	if (!priv || !priv->kms)
+		return;
+
+	drm_mode_config_helper_resume(ddev);
+}
+
+void msm_kms_shutdown(struct platform_device *pdev)
+{
+	struct msm_drm_private *priv = platform_get_drvdata(pdev);
+	struct drm_device *drm = priv ? priv->dev : NULL;
+
+	/*
+	 * Shutdown the hw if we're far enough along where things might be on.
+	 * If we run this too early, we'll end up panicking in any variety of
+	 * places. Since we don't register the drm device until late in
+	 * msm_drm_init, drm_dev->registered is used as an indicator that the
+	 * shutdown will be successful.
+	 */
+	if (drm && drm->registered && priv->kms)
+		drm_atomic_helper_shutdown(drm);
+}

drivers/gpu/drm/msm/msm_kms.h

@@ -195,4 +195,7 @@ static inline void msm_kms_destroy(struct msm_kms *kms)
 	drm_for_each_crtc_reverse(crtc, dev) \
 		for_each_if (drm_crtc_mask(crtc) & (crtc_mask))
 
+int msm_drm_kms_init(struct device *dev, const struct drm_driver *drv);
+void msm_drm_kms_uninit(struct device *dev);
+
 #endif /* __MSM_KMS_H__ */