From patchwork Tue Jan 7 18:58:04 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Boris Brezillon X-Patchwork-Id: 11321599 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 5E4E9921 for ; Tue, 7 Jan 2020 18:58:27 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 4668420848 for ; Tue, 7 Jan 2020 18:58:27 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 4668420848 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=collabora.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=dri-devel-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id D54A66E12D; Tue, 7 Jan 2020 18:58:20 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from bhuna.collabora.co.uk (bhuna.collabora.co.uk [IPv6:2a00:1098:0:82:1000:25:2eeb:e3e3]) by gabe.freedesktop.org (Postfix) with ESMTPS id DC01B6E128 for ; Tue, 7 Jan 2020 18:58:18 +0000 (UTC) Received: from localhost.localdomain (unknown [IPv6:2a01:e0a:2c:6930:5cf4:84a1:2763:fe0d]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) (Authenticated sender: bbrezillon) by bhuna.collabora.co.uk (Postfix) with ESMTPSA id 7D8052904BB; Tue, 7 Jan 2020 18:58:17 +0000 (GMT) From: Boris Brezillon To: Andrzej Hajda , Neil Armstrong , Laurent Pinchart , Jonas Karlman , Jernej Skrabec , Daniel Vetter Subject: [PATCH v2 2/5] Revert "drm/bridge: Add the necessary bits to support bus format negotiation" Date: Tue, 7 Jan 2020 19:58:04 +0100 Message-Id: <20200107185807.606999-3-boris.brezillon@collabora.com> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20200107185807.606999-1-boris.brezillon@collabora.com> References: <20200107185807.606999-1-boris.brezillon@collabora.com> MIME-Version: 1.0 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Boris Brezillon , dri-devel@lists.freedesktop.org Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" This reverts commit e351e4d5eaec ("drm/bridge: Add the necessary bits to support bus format negotiation"). Commit 6ed7e9625fa6 ("drm/bridge: Add a drm_bridge_state object") introduced a circular dependency between drm.ko and drm_kms_helper.ko which uncovered a misdesign in how the whole thing was implemented. Let's revert all patches depending on the bridge_state infrastructure for now. Signed-off-by: Boris Brezillon --- drivers/gpu/drm/drm_bridge.c | 267 +---------------------------------- include/drm/drm_bridge.h | 124 ---------------- 2 files changed, 1 insertion(+), 390 deletions(-) diff --git a/drivers/gpu/drm/drm_bridge.c b/drivers/gpu/drm/drm_bridge.c index 37400607e9b7..8e4b799150b0 100644 --- a/drivers/gpu/drm/drm_bridge.c +++ b/drivers/gpu/drm/drm_bridge.c @@ -671,261 +671,13 @@ static int drm_atomic_bridge_check(struct drm_bridge *bridge, return 0; } -/** - * drm_atomic_helper_bridge_propagate_bus_fmt() - Propagate output format to - * the input end of a bridge - * @bridge: bridge control structure - * @bridge_state: new bridge state - * @crtc_state: new CRTC state - * @conn_state: new connector state - * @output_fmt: tested output bus format - * @num_input_fmts: will contain the size of the returned array - * - * This helper is a pluggable implementation of the - * &drm_bridge_funcs.atomic_get_input_bus_fmts operation for bridges that don't - * modify the bus configuration between their input and their output. It - * returns an array of input formats with a single element set to @output_fmt. - * - * RETURNS: - * a valid format array of size @num_input_fmts, or NULL if the allocation - * failed - */ -u32 * -drm_atomic_helper_bridge_propagate_bus_fmt(struct drm_bridge *bridge, - struct drm_bridge_state *bridge_state, - struct drm_crtc_state *crtc_state, - struct drm_connector_state *conn_state, - u32 output_fmt, - unsigned int *num_input_fmts) -{ - u32 *input_fmts; - - input_fmts = kzalloc(sizeof(*input_fmts), GFP_KERNEL); - if (!input_fmts) { - *num_input_fmts = 0; - return NULL; - } - - *num_input_fmts = 1; - input_fmts[0] = output_fmt; - return input_fmts; -} -EXPORT_SYMBOL(drm_atomic_helper_bridge_propagate_bus_fmt); - -static int select_bus_fmt_recursive(struct drm_bridge *first_bridge, - struct drm_bridge *cur_bridge, - struct drm_crtc_state *crtc_state, - struct drm_connector_state *conn_state, - u32 out_bus_fmt) -{ - struct drm_bridge_state *cur_state; - unsigned int num_in_bus_fmts, i; - struct drm_bridge *prev_bridge; - u32 *in_bus_fmts; - int ret; - - prev_bridge = drm_bridge_get_prev_bridge(cur_bridge); - cur_state = drm_atomic_get_new_bridge_state(crtc_state->state, - cur_bridge); - if (WARN_ON(!cur_state)) - return -EINVAL; - - /* - * If bus format negotiation is not supported by this bridge, let's - * pass MEDIA_BUS_FMT_FIXED to the previous bridge in the chain and - * hope that it can handle this situation gracefully (by providing - * appropriate default values). - */ - if (!cur_bridge->funcs->atomic_get_input_bus_fmts) { - if (cur_bridge != first_bridge) { - ret = select_bus_fmt_recursive(first_bridge, - prev_bridge, crtc_state, - conn_state, - MEDIA_BUS_FMT_FIXED); - if (ret) - return ret; - } - - cur_state->input_bus_cfg.format = MEDIA_BUS_FMT_FIXED; - cur_state->output_bus_cfg.format = out_bus_fmt; - return 0; - } - - in_bus_fmts = cur_bridge->funcs->atomic_get_input_bus_fmts(cur_bridge, - cur_state, - crtc_state, - conn_state, - out_bus_fmt, - &num_in_bus_fmts); - if (!num_in_bus_fmts) - return -ENOTSUPP; - else if (!in_bus_fmts) - return -ENOMEM; - - if (first_bridge == cur_bridge) { - cur_state->input_bus_cfg.format = in_bus_fmts[0]; - cur_state->output_bus_cfg.format = out_bus_fmt; - kfree(in_bus_fmts); - return 0; - } - - for (i = 0; i < num_in_bus_fmts; i++) { - ret = select_bus_fmt_recursive(first_bridge, prev_bridge, - crtc_state, conn_state, - in_bus_fmts[i]); - if (ret != -ENOTSUPP) - break; - } - - if (!ret) { - cur_state->input_bus_cfg.format = in_bus_fmts[i]; - cur_state->output_bus_cfg.format = out_bus_fmt; - } - - kfree(in_bus_fmts); - return ret; -} - -/* - * This function is called by &drm_atomic_bridge_chain_check() just before - * calling &drm_bridge_funcs.atomic_check() on all elements of the chain. - * It performs bus format negotiation between bridge elements. The negotiation - * happens in reverse order, starting from the last element in the chain up to - * @bridge. - * - * Negotiation starts by retrieving supported output bus formats on the last - * bridge element and testing them one by one. The test is recursive, meaning - * that for each tested output format, the whole chain will be walked backward, - * and each element will have to choose an input bus format that can be - * transcoded to the requested output format. When a bridge element does not - * support transcoding into a specific output format -ENOTSUPP is returned and - * the next bridge element will have to try a different format. If none of the - * combinations worked, -ENOTSUPP is returned and the atomic modeset will fail. - * - * This implementation is relying on - * &drm_bridge_funcs.atomic_get_output_bus_fmts() and - * &drm_bridge_funcs.atomic_get_input_bus_fmts() to gather supported - * input/output formats. - * - * When &drm_bridge_funcs.atomic_get_output_bus_fmts() is not implemented by - * the last element of the chain, &drm_atomic_bridge_chain_select_bus_fmts() - * tries a single format: &drm_connector.display_info.bus_formats[0] if - * available, MEDIA_BUS_FMT_FIXED otherwise. - * - * When &drm_bridge_funcs.atomic_get_input_bus_fmts() is not implemented, - * &drm_atomic_bridge_chain_select_bus_fmts() skips the negotiation on the - * bridge element that lacks this hook and asks the previous element in the - * chain to try MEDIA_BUS_FMT_FIXED. It's up to bridge drivers to decide what - * to do in that case (fail if they want to enforce bus format negotiation, or - * provide a reasonable default if they need to support pipelines where not - * all elements support bus format negotiation). - */ -static int -drm_atomic_bridge_chain_select_bus_fmts(struct drm_bridge *bridge, - struct drm_crtc_state *crtc_state, - struct drm_connector_state *conn_state) -{ - struct drm_connector *conn = conn_state->connector; - struct drm_encoder *encoder = bridge->encoder; - struct drm_bridge_state *last_bridge_state; - unsigned int i, num_out_bus_fmts; - struct drm_bridge *last_bridge; - u32 *out_bus_fmts; - int ret = 0; - - last_bridge = list_last_entry(&encoder->bridge_chain, - struct drm_bridge, chain_node); - last_bridge_state = drm_atomic_get_new_bridge_state(crtc_state->state, - last_bridge); - if (WARN_ON(!last_bridge_state)) - return -EINVAL; - - if (last_bridge->funcs->atomic_get_output_bus_fmts) { - const struct drm_bridge_funcs *funcs = last_bridge->funcs; - - out_bus_fmts = funcs->atomic_get_output_bus_fmts(last_bridge, - last_bridge_state, - crtc_state, - conn_state, - &num_out_bus_fmts); - if (!num_out_bus_fmts) - return -ENOTSUPP; - else if (!out_bus_fmts) - return -ENOMEM; - } else { - num_out_bus_fmts = 1; - out_bus_fmts = kmalloc(sizeof(*out_bus_fmts), GFP_KERNEL); - if (!out_bus_fmts) - return -ENOMEM; - - if (conn->display_info.num_bus_formats && - conn->display_info.bus_formats) - out_bus_fmts[0] = conn->display_info.bus_formats[0]; - else - out_bus_fmts[0] = MEDIA_BUS_FMT_FIXED; - } - - for (i = 0; i < num_out_bus_fmts; i++) { - ret = select_bus_fmt_recursive(bridge, last_bridge, crtc_state, - conn_state, out_bus_fmts[i]); - if (ret != -ENOTSUPP) - break; - } - - kfree(out_bus_fmts); - - return ret; -} - -static void -drm_atomic_bridge_propagate_bus_flags(struct drm_bridge *bridge, - struct drm_connector *conn, - struct drm_atomic_state *state) -{ - struct drm_bridge_state *bridge_state, *next_bridge_state; - struct drm_bridge *next_bridge; - u32 output_flags; - - bridge_state = drm_atomic_get_new_bridge_state(state, bridge); - next_bridge = drm_bridge_get_next_bridge(bridge); - - /* - * Let's try to apply the most common case here, that is, propagate - * display_info flags for the last bridge, and propagate the input - * flags of the next bridge element to the output end of the current - * bridge when the bridge is not the last one. - * There are exceptions to this rule, like when signal inversion is - * happening at the board level, but that's something drivers can deal - * with from their &drm_bridge_funcs.atomic_check() implementation by - * simply overriding the flags value we've set here. - */ - if (!next_bridge) { - output_flags = conn->display_info.bus_flags; - } else { - next_bridge_state = drm_atomic_get_new_bridge_state(state, - next_bridge); - output_flags = next_bridge_state->input_bus_cfg.flags; - } - - bridge_state->output_bus_cfg.flags = output_flags; - - /* - * Propage the output flags to the input end of the bridge. Again, it's - * not necessarily what all bridges want, but that's what most of them - * do, and by doing that by default we avoid forcing drivers to - * duplicate the "dummy propagation" logic. - */ - bridge_state->input_bus_cfg.flags = output_flags; -} - /** * drm_atomic_bridge_chain_check() - Do an atomic check on the bridge chain * @bridge: bridge control structure * @crtc_state: new CRTC state * @conn_state: new connector state * - * First trigger a bus format negotiation before calling - * &drm_bridge_funcs.atomic_check() (falls back on + * Calls &drm_bridge_funcs.atomic_check() (falls back on * &drm_bridge_funcs.mode_fixup()) op for all the bridges in the encoder chain, * starting from the last bridge to the first. These are called before calling * &drm_encoder_helper_funcs.atomic_check() @@ -937,29 +689,12 @@ int drm_atomic_bridge_chain_check(struct drm_bridge *bridge, struct drm_crtc_state *crtc_state, struct drm_connector_state *conn_state) { - struct drm_connector *conn = conn_state->connector; struct drm_encoder *encoder = bridge->encoder; struct drm_bridge *iter; - int ret; - - ret = drm_atomic_bridge_chain_select_bus_fmts(bridge, crtc_state, - conn_state); - if (ret) - return ret; list_for_each_entry_reverse(iter, &encoder->bridge_chain, chain_node) { int ret; - /* - * Bus flags are propagated by default. If a bridge needs to - * tweak the input bus flags for any reason, it should happen - * in its &drm_bridge_funcs.atomic_check() implementation such - * that preceding bridges in the chain can propagate the new - * bus flags. - */ - drm_atomic_bridge_propagate_bus_flags(iter, conn, - crtc_state->state); - ret = drm_atomic_bridge_check(iter, crtc_state, conn_state); if (ret) return ret; diff --git a/include/drm/drm_bridge.h b/include/drm/drm_bridge.h index 46e15526b087..ae0595c70132 100644 --- a/include/drm/drm_bridge.h +++ b/include/drm/drm_bridge.h @@ -35,38 +35,6 @@ struct drm_bridge; struct drm_bridge_timings; struct drm_panel; -/** - * struct drm_bus_cfg - bus configuration - * - * This structure stores the configuration of a physical bus between two - * components in an output pipeline, usually between two bridges, an encoder - * and a bridge, or a bridge and a connector. - * - * The bus configuration is stored in &drm_bridge_state separately for the - * input and output buses, as seen from the point of view of each bridge. The - * bus configuration of a bridge output is usually identical to the - * configuration of the next bridge's input, but may differ if the signals are - * modified between the two bridges, for instance by an inverter on the board. - * The input and output configurations of a bridge may differ if the bridge - * modifies the signals internally, for instance by performing format - * conversion, or modifying signals polarities. - */ -struct drm_bus_cfg { - /** - * @format: format used on this bus (one of the MEDIA_BUS_FMT_* format) - * - * This field should not be directly modified by drivers - * (&drm_atomic_bridge_chain_select_bus_fmts() takes care of the bus - * format negotiation). - */ - u32 format; - - /** - * @flags: DRM_BUS_* flags used on this bus - */ - u32 flags; -}; - /** * struct drm_bridge_state - Atomic bridge state object * @base: inherit from &drm_private_state @@ -76,16 +44,6 @@ struct drm_bridge_state { struct drm_private_state base; struct drm_bridge *bridge; - - /** - * @input_bus_cfg: input bus configuration - */ - struct drm_bus_cfg input_bus_cfg; - - /** - * @output_bus_cfg: input bus configuration - */ - struct drm_bus_cfg output_bus_cfg; }; static inline struct drm_bridge_state * @@ -429,72 +387,6 @@ struct drm_bridge_funcs { void (*atomic_destroy_state)(struct drm_bridge *bridge, struct drm_bridge_state *state); - /** - * @atomic_get_output_bus_fmts: - * - * Return the supported bus formats on the output end of a bridge. - * The returned array must be allocated with kmalloc() and will be - * freed by the caller. If the allocation fails, NULL should be - * returned. num_output_fmts must be set to the returned array size. - * Formats listed in the returned array should be listed in decreasing - * preference order (the core will try all formats until it finds one - * that works). - * - * This method is only called on the last element of the bridge chain - * as part of the bus format negotiation process that happens in - * &drm_atomic_bridge_chain_select_bus_fmts(). - * This method is optional. When not implemented, the core will - * fall back to &drm_connector.display_info.bus_formats[0] if - * &drm_connector.display_info.num_bus_formats > 0, - * or to MEDIA_BUS_FMT_FIXED otherwise. - */ - u32 *(*atomic_get_output_bus_fmts)(struct drm_bridge *bridge, - struct drm_bridge_state *bridge_state, - struct drm_crtc_state *crtc_state, - struct drm_connector_state *conn_state, - unsigned int *num_output_fmts); - - /** - * @atomic_get_input_bus_fmts: - * - * Return the supported bus formats on the input end of a bridge for - * a specific output bus format. - * - * The returned array must be allocated with kmalloc() and will be - * freed by the caller. If the allocation fails, NULL should be - * returned. num_output_fmts must be set to the returned array size. - * Formats listed in the returned array should be listed in decreasing - * preference order (the core will try all formats until it finds one - * that works). When the format is not supported NULL should be - * returned and *num_output_fmts should be set to 0. - * - * This method is called on all elements of the bridge chain as part of - * the bus format negotiation process that happens in - * &drm_atomic_bridge_chain_select_bus_fmts(). - * This method is optional. When not implemented, the core will bypass - * bus format negotiation on this element of the bridge without - * failing, and the previous element in the chain will be passed - * MEDIA_BUS_FMT_FIXED as its output bus format. - * - * Bridge drivers that need to support being linked to bridges that are - * not supporting bus format negotiation should handle the - * output_fmt == MEDIA_BUS_FMT_FIXED case appropriately, by selecting a - * sensible default value or extracting this information from somewhere - * else (FW property, &drm_display_mode, &drm_display_info, ...) - * - * Note: Even if input format selection on the first bridge has no - * impact on the negotiation process (bus format negotiation stops once - * we reach the first element of the chain), drivers are expected to - * return accurate input formats as the input format may be used to - * configure the CRTC output appropriately. - */ - u32 *(*atomic_get_input_bus_fmts)(struct drm_bridge *bridge, - struct drm_bridge_state *bridge_state, - struct drm_crtc_state *crtc_state, - struct drm_connector_state *conn_state, - u32 output_fmt, - unsigned int *num_input_fmts); - /** * @atomic_check: * @@ -509,14 +401,6 @@ struct drm_bridge_funcs { * called when &drm_bridge_funcs.atomic_check() is implemented, so only * one of them should be provided. * - * If drivers need to tweak &drm_bridge_state.input_bus_cfg.flags or - * &drm_bridge_state.output_bus_cfg.flags it should should happen in - * this function. By default the &drm_bridge_state.output_bus_cfg.flags - * field is set to the next bridge - * &drm_bridge_state.input_bus_cfg.flags value or - * &drm_connector.display_info.bus_flags if the bridge is the last - * element in the chain. - * * RETURNS: * zero if the check passed, a negative error code otherwise. */ @@ -704,14 +588,6 @@ void drm_atomic_bridge_chain_pre_enable(struct drm_bridge *bridge, void drm_atomic_bridge_chain_enable(struct drm_bridge *bridge, struct drm_atomic_state *state); -u32 * -drm_atomic_helper_bridge_propagate_bus_fmt(struct drm_bridge *bridge, - struct drm_bridge_state *bridge_state, - struct drm_crtc_state *crtc_state, - struct drm_connector_state *conn_state, - u32 output_fmt, - unsigned int *num_input_fmts); - void __drm_atomic_helper_bridge_reset(struct drm_bridge *bridge, struct drm_bridge_state *state); void __drm_atomic_helper_bridge_duplicate_state(struct drm_bridge *bridge,