From: Hugo Villeneuve <[email protected]> Since commit 56de5e305d4b ("clk: renesas: r9a07g044: Add MSTOP for RZ/G2L") we may get the following kernel panic, for some panels, when rebooting:
systemd-shutdown[1]: Rebooting. Call trace: ... do_serror+0x28/0x68 el1h_64_error_handler+0x34/0x50 el1h_64_error+0x6c/0x70 rzg2l_mipi_dsi_host_transfer+0x114/0x458 (P) mipi_dsi_device_transfer+0x44/0x58 mipi_dsi_dcs_set_display_off_multi+0x9c/0xc4 ili9881c_unprepare+0x38/0x88 drm_panel_unprepare+0xbc/0x108 This happens for panels that need to send MIPI-DSI commands in their unprepare() callback. Since the MIPI-DSI interface is stopped at that point, rzg2l_mipi_dsi_host_transfer() triggers the kernel panic. Fix by moving rzg2l_mipi_dsi_stop() to new callback function rzg2l_mipi_dsi_atomic_post_disable(). With this change we now have the correct power-down/stop sequence: systemd-shutdown[1]: Rebooting. rzg2l-mipi-dsi 10850000.dsi: rzg2l_mipi_dsi_atomic_disable(): entry ili9881c-dsi 10850000.dsi.0: ili9881c_unprepare(): entry rzg2l-mipi-dsi 10850000.dsi: rzg2l_mipi_dsi_atomic_post_disable(): entry reboot: Restarting system Suggested-by: Biju Das <[email protected]> Signed-off-by: Hugo Villeneuve <[email protected]> --- Tested on a custom RZ/G2L board with three different panels/drivers: ili9881c -> sending DSI commands in unprepare() jd9365da -> not sending DSI commands in unprepare() st7703 -> not sending DSI commands in unprepare() --- drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c index 3b52dfc0ea1e0..b164e3a62cc2f 100644 --- a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c +++ b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c @@ -646,6 +646,13 @@ static void rzg2l_mipi_dsi_atomic_disable(struct drm_bridge *bridge, rzg2l_mipi_dsi_stop_video(dsi); rzg2l_mipi_dsi_stop_hs_clock(dsi); +} + +static void rzg2l_mipi_dsi_atomic_post_disable(struct drm_bridge *bridge, + struct drm_atomic_state *state) +{ + struct rzg2l_mipi_dsi *dsi = bridge_to_rzg2l_mipi_dsi(bridge); + rzg2l_mipi_dsi_stop(dsi); } @@ -681,6 +688,7 @@ static const struct drm_bridge_funcs rzg2l_mipi_dsi_bridge_ops = { .atomic_pre_enable = rzg2l_mipi_dsi_atomic_pre_enable, .atomic_enable = rzg2l_mipi_dsi_atomic_enable, .atomic_disable = rzg2l_mipi_dsi_atomic_disable, + .atomic_post_disable = rzg2l_mipi_dsi_atomic_post_disable, .mode_valid = rzg2l_mipi_dsi_bridge_mode_valid, }; base-commit: 0f61b1860cc3f52aef9036d7235ed1f017632193 -- 2.47.3
