[RFC PATCH 11/11] drm: exynos: mixer: Add interconnect support

From: Artur ÅwigoÅ
Date: Tue Jul 23 2019 - 08:20:51 EST


From: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx>

This patch adds interconnect support to exynos-mixer. Please note that the
mixer works the same as before when CONFIG_INTERCONNECT is 'n'.

Co-developed-by: Artur ÅwigoÅ <a.swigon@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Artur ÅwigoÅ <a.swigon@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx>
---
drivers/gpu/drm/exynos/exynos_mixer.c | 68 +++++++++++++++++++++++++--
1 file changed, 63 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/exynos/exynos_mixer.c b/drivers/gpu/drm/exynos/exynos_mixer.c
index 7b24338fad3c..fb763854b300 100644
--- a/drivers/gpu/drm/exynos/exynos_mixer.c
+++ b/drivers/gpu/drm/exynos/exynos_mixer.c
@@ -13,6 +13,7 @@
#include <linux/component.h>
#include <linux/delay.h>
#include <linux/i2c.h>
+#include <linux/interconnect.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/kernel.h>
@@ -97,6 +98,7 @@ struct mixer_context {
struct exynos_drm_crtc *crtc;
struct exynos_drm_plane planes[MIXER_WIN_NR];
unsigned long flags;
+ struct icc_path *soc_path;

int irq;
void __iomem *mixer_regs;
@@ -931,6 +933,37 @@ static void mixer_disable_vblank(struct exynos_drm_crtc *crtc)
mixer_reg_writemask(mixer_ctx, MXR_INT_EN, 0, MXR_INT_EN_VSYNC);
}

+static void mixer_set_memory_bandwidth(struct exynos_drm_crtc *crtc)
+{
+ struct drm_display_mode *mode = &crtc->base.state->adjusted_mode;
+ struct mixer_context *ctx = crtc->ctx;
+ unsigned long bw, bandwidth = 0;
+ int i, j, sub;
+
+ for (i = 0; i < MIXER_WIN_NR; i++) {
+ struct drm_plane *plane = &ctx->planes[i].base;
+ const struct drm_format_info *format;
+
+ if (plane->state && plane->state->crtc && plane->state->fb) {
+ format = plane->state->fb->format;
+ bw = mode->hdisplay * mode->vdisplay *
+ drm_mode_vrefresh(mode);
+ if (mode->flags & DRM_MODE_FLAG_INTERLACE)
+ bw /= 2;
+ for (j = 0; j < format->num_planes; j++) {
+ sub = j ? (format->vsub * format->hsub) : 1;
+ bandwidth += format->cpp[j] * bw / sub;
+ }
+ }
+ }
+
+ /* add 20% safety margin */
+ bandwidth = 5UL * bandwidth / 4;
+
+ pr_info("exynos-mixer: safe bandwidth %ld Bps\n", bandwidth);
+ icc_set_bw(ctx->soc_path, 0, Bps_to_icc(bandwidth));
+}
+
static void mixer_atomic_begin(struct exynos_drm_crtc *crtc)
{
struct mixer_context *ctx = crtc->ctx;
@@ -982,6 +1015,7 @@ static void mixer_atomic_flush(struct exynos_drm_crtc *crtc)
if (!test_bit(MXR_BIT_POWERED, &mixer_ctx->flags))
return;

+ mixer_set_memory_bandwidth(crtc);
mixer_enable_sync(mixer_ctx);
exynos_crtc_handle_event(crtc);
}
@@ -1029,6 +1063,7 @@ static void mixer_disable(struct exynos_drm_crtc *crtc)
for (i = 0; i < MIXER_WIN_NR; i++)
mixer_disable_plane(crtc, &ctx->planes[i]);

+ mixer_set_memory_bandwidth(crtc);
exynos_drm_pipe_clk_enable(crtc, false);

pm_runtime_put(ctx->dev);
@@ -1220,12 +1255,22 @@ static int mixer_probe(struct platform_device *pdev)
struct device *dev = &pdev->dev;
const struct mixer_drv_data *drv;
struct mixer_context *ctx;
+ struct icc_path *path;
int ret;

+ /*
+ * Returns NULL if CONFIG_INTERCONNECT is disabled.
+ * May return ERR_PTR(-EPROBE_DEFER).
+ */
+ path = of_icc_get(dev, NULL);
+ if (IS_ERR(path))
+ return PTR_ERR(path);
+
ctx = devm_kzalloc(&pdev->dev, sizeof(*ctx), GFP_KERNEL);
if (!ctx) {
DRM_DEV_ERROR(dev, "failed to alloc mixer context.\n");
- return -ENOMEM;
+ ret = -ENOMEM;
+ goto err;
}

drv = of_device_get_match_data(dev);
@@ -1233,6 +1278,7 @@ static int mixer_probe(struct platform_device *pdev)
ctx->pdev = pdev;
ctx->dev = dev;
ctx->mxr_ver = drv->version;
+ ctx->soc_path = path;

if (drv->is_vp_enabled)
__set_bit(MXR_BIT_VP_ENABLED, &ctx->flags);
@@ -1242,17 +1288,29 @@ static int mixer_probe(struct platform_device *pdev)
platform_set_drvdata(pdev, ctx);

ret = component_add(&pdev->dev, &mixer_component_ops);
- if (!ret)
- pm_runtime_enable(dev);
+ if (ret < 0)
+ goto err;
+
+ pm_runtime_enable(dev);
+
+ return 0;
+
+err:
+ icc_put(path);

return ret;
}

static int mixer_remove(struct platform_device *pdev)
{
- pm_runtime_disable(&pdev->dev);
+ struct device *dev = &pdev->dev;
+ struct mixer_context *ctx = dev_get_drvdata(dev);

- component_del(&pdev->dev, &mixer_component_ops);
+ pm_runtime_disable(dev);
+
+ component_del(dev, &mixer_component_ops);
+
+ icc_put(ctx->soc_path);

return 0;
}
--
2.17.1