Attachment 136969 Details for Bug 82880 – [PATCH] drm/i915: Fix DSI panels with v1 MIPI sequences without a DEASSERT sequence v2

[patch] [PATCH] drm/i915: Fix DSI panels with v1 MIPI sequences without a DEASSERT sequence v2

0001-drm-i915-Fix-DSI-panels-with-v1-MIPI-sequences-witho.patch (text/plain), 5.89 KB, created by Hans de Goede on 2018-01-26 08:40:46 UTC

(hide)

Description:

Filename:

MIME Type:

Creator: Hans de Goede

Created: 2018-01-26 08:40:46 UTC

Size: 5.89 KB

patch

obsolete

>From 03d43f0bc46277dafdb066411f59ca348d9af23a Mon Sep 17 00:00:00 2001
>From: Hans de Goede <hdegoede@redhat.com>
>Date: Thu, 25 Jan 2018 23:15:51 +0100
>Subject: [PATCH] drm/i915: Fix DSI panels with v1 MIPI sequences without a
> DEASSERT sequence v2
>
>So far models of the Dell Venue 8 Pro, with a panel with MIPI panel
>index = 3, one of which has been kindly provided to me by Jan Brummer,
>where not working with the i915 driver, giving a black screen on the
>first modeset.
>
>The problem with at least these Dells is that their VBT defines a MIPI
>ASSERT sequence, but not a DEASSERT sequence. Instead they DEASSERT the
>reset in their INIT_OTP sequence, but the deassert must be done before
>calling intel_dsi_device_ready(), so that is too late.
>
>Simply doing the INIT_OTP sequence earlier is not enough to fix this,
>because the INIT_OTP sequence also sends various MIPI packets to the
>panel, which can only happen after calling intel_dsi_device_ready().
>
>This commit fixes this by splitting the INIT_OTP sequence into everything
>before the first DSI packet and everything else, including the first DSI
>packet. The first part (everything before the first DSI packet) is then
>used as deassert sequence.
>
>Changed in v2:
>-Split the init OTP sequence into a deassert reset and the actual init
> OTP sequence, instead of calling it earlier and then having the first
> mipi_exec_send_packet() call call intel_dsi_device_ready().
>
>BugLink: https://bugs.freedesktop.org/show_bug.cgi?id=82880
>Related: https://bugs.freedesktop.org/show_bug.cgi?id=101205
>Cc: Jan-Michael Brummer <jan.brummer@tabos.org>
>Reported-by: Jan-Michael Brummer <jan.brummer@tabos.org>
>Tested-by: Hans de Goede <hdegoede@redhat.com>
>Signed-off-by: Hans de Goede <hdegoede@redhat.com>
>---
> drivers/gpu/drm/i915/intel_dsi.c     |  1 +
> drivers/gpu/drm/i915/intel_dsi.h     |  2 +
> drivers/gpu/drm/i915/intel_dsi_vbt.c | 82 ++++++++++++++++++++++++++++++++++++
> 3 files changed, 85 insertions(+)
>
>diff --git a/drivers/gpu/drm/i915/intel_dsi.c b/drivers/gpu/drm/i915/intel_dsi.c
>index 5b669a3f01b1..e62232762d84 100644
>--- a/drivers/gpu/drm/i915/intel_dsi.c
>+++ b/drivers/gpu/drm/i915/intel_dsi.c
>@@ -1641,6 +1641,7 @@ static void intel_dsi_encoder_destroy(struct drm_encoder *encoder)
> 	if (intel_dsi->gpio_panel)
> 		gpiod_put(intel_dsi->gpio_panel);
> 
>+	kfree(intel_dsi->deassert_seq);
> 	intel_encoder_destroy(encoder);
> }
> 
>diff --git a/drivers/gpu/drm/i915/intel_dsi.h b/drivers/gpu/drm/i915/intel_dsi.h
>index 7afeb9580f41..5895588144ad 100644
>--- a/drivers/gpu/drm/i915/intel_dsi.h
>+++ b/drivers/gpu/drm/i915/intel_dsi.h
>@@ -46,6 +46,8 @@ struct intel_dsi {
> 
> 	struct intel_connector *attached_connector;
> 
>+	u8 *deassert_seq;
>+
> 	/* bit mask of ports being driven */
> 	u16 ports;
> 
>diff --git a/drivers/gpu/drm/i915/intel_dsi_vbt.c b/drivers/gpu/drm/i915/intel_dsi_vbt.c
>index 91c07b0c8db9..84664f79cbef 100644
>--- a/drivers/gpu/drm/i915/intel_dsi_vbt.c
>+++ b/drivers/gpu/drm/i915/intel_dsi_vbt.c
>@@ -499,6 +499,86 @@ int intel_dsi_vbt_get_modes(struct intel_dsi *intel_dsi)
> 	return 1;
> }
> 
>+/*
>+ * Get len of pre-fixed deassert from init OTP, skip all delay + gpio operands
>+ * and stop at the first DSI packet op.
>+ */
>+static int intel_vbi_get_deassert_len(const u8 *data, int total)
>+{
>+	int index, len;
>+
>+	/* index = 1 to skip sequence byte */
>+	for (index = 1; index < total; index += len) {
>+		switch (data[index]) {
>+		case MIPI_SEQ_ELEM_SEND_PKT:
>+			return index;
>+		case MIPI_SEQ_ELEM_DELAY:
>+			len = 5; /* 1 byte for operand + uint32 */
>+			break;
>+		case MIPI_SEQ_ELEM_GPIO:
>+			len = 3; /* 1 byte for op, 1 for gpio_nr, 1 for value */
>+			break;
>+		default:
>+			return 0;
>+		}
>+	}
>+
>+	return 0;
>+}
>+
>+/*
>+ * Some v1 VBT MIPI sequences do the deassert in the init OTP sequence.
>+ * The deassert must be done before calling intel_dsi_device_ready, so for
>+ * these devices we split the init OTP sequence into a deassert sequence and
>+ * the actual init OTP part.
>+ */
>+static void intel_dsi_fixup_dsi_sequences(struct intel_dsi *intel_dsi)
>+{
>+	struct drm_i915_private *dev_priv = to_i915(intel_dsi->base.base.dev);
>+	int init_otp_index, len;
>+	u8 *init_otp;
>+
>+	/* Limit this to VLV for now. */
>+	if (!IS_VALLEYVIEW(dev_priv))
>+		return;
>+
>+	/* Limit this to v1 vid-mode sequences */
>+	if (intel_dsi->operation_mode != INTEL_DSI_VIDEO_MODE ||
>+	    dev_priv->vbt.dsi.seq_version != 1)
>+		return;
>+
>+	/* Only do this if there are otp and assert seqs and no deassert seq */
>+	if (!dev_priv->vbt.dsi.sequence[MIPI_SEQ_INIT_OTP] ||
>+	    !dev_priv->vbt.dsi.sequence[MIPI_SEQ_ASSERT_RESET] ||
>+	    dev_priv->vbt.dsi.sequence[MIPI_SEQ_DEASSERT_RESET])
>+		return;
>+
>+	/* The deassert-sequence ends at the first DSI packet */
>+	init_otp_index = dev_priv->vbt.dsi.sequence[MIPI_SEQ_INIT_OTP] -
>+			 (const u8 *)dev_priv->vbt.dsi.data;
>+	init_otp = dev_priv->vbt.dsi.data + init_otp_index;
>+	len = dev_priv->vbt.dsi.size - init_otp_index;
>+	len = intel_vbi_get_deassert_len(init_otp, len);
>+	if (!len)
>+		return;
>+
>+	DRM_DEBUG_KMS("Using init OTP fragment to deassert reset\n");
>+
>+	/* Copy the fragment, update seq byte and terminate it */
>+	intel_dsi->deassert_seq = kmemdup(init_otp, len + 1, GFP_KERNEL);
>+	if (!intel_dsi->deassert_seq)
>+		return;
>+	intel_dsi->deassert_seq[0] = MIPI_SEQ_DEASSERT_RESET;
>+	intel_dsi->deassert_seq[len] = MIPI_SEQ_ELEM_END;
>+	/* Use the copy for deassert */
>+	dev_priv->vbt.dsi.sequence[MIPI_SEQ_DEASSERT_RESET] =
>+		intel_dsi->deassert_seq;
>+	/* Replace the last byte of the fragment with init OTP seq byte */
>+	init_otp[len - 1] = MIPI_SEQ_INIT_OTP;
>+	/* And make MIPI_MIPI_SEQ_INIT_OTP point to it */
>+	dev_priv->vbt.dsi.sequence[MIPI_SEQ_INIT_OTP] = init_otp + len - 1;
>+}
>+
> bool intel_dsi_vbt_init(struct intel_dsi *intel_dsi, u16 panel_id)
> {
> 	struct drm_device *dev = intel_dsi->base.base.dev;
>@@ -794,5 +874,7 @@ bool intel_dsi_vbt_init(struct intel_dsi *intel_dsi, u16 panel_id)
> 		mipi_dsi_attach(intel_dsi->dsi_hosts[port]->device);
> 	}
> 
>+	intel_dsi_fixup_dsi_sequences(intel_dsi);
>+
> 	return true;
> }
>-- 
>2.14.3
>

Actions: View | Splinter Review

Attachments on bug 82880: 104995 | 106968 | 106969 | 111132 | 113510 | 123802 | 136952 | 136958 | 136969

Use of freedesktop.org services, including Bugzilla, is subject to our Code of Conduct. How we collect and use information is described in our Privacy Policy.