Hi Hans,
On Tue, Aug 27, 2019 at 11:07:56AM +0200, Hans Verkuil wrote:
> Hi Laurent,
>
> I tried this series with my Pandaboard, but it broke my Pandaboard. After
> doing a git bisect it ended up with this patch as the culprit.
>
> If I boot my Pandaboard I get this:
>
> [ 3.271881] omapdss_dss 58000000.dss: 58000000.dss supply vdda_video not found, using dummy regulator
> [ 3.285369] omapdss_dss 58000000.dss: 58000000.dss supply vdda_video not found, using dummy regulator
> [ 24.286773] rcu: INFO: rcu_sched self-detected stall on CPU
> [ 24.292388] rcu: 0-...!: (1306 ticks this GP) idle=6b6/1/0x40000002 softirq=85/85 fqs=19
> [ 24.300689] (t=2100 jiffies g=-1063 q=10)
> [ 24.304809] rcu: rcu_sched kthread starved for 2058 jiffies! g-1063 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=1
> [ 24.315124] rcu: RCU grace-period kthread stack dump:
> [ 24.315124] rcu_sched I 0 10 2 0x00000000
> [ 24.325805] [<c09b7130>] (__schedule) from [<c09b73a8>] (schedule+0x40/0xc0)
> [ 24.332885] [<c09b73a8>] (schedule) from [<c09ba9d0>] (schedule_timeout+0x174/0x2a8)
> [ 24.340698] [<c09ba9d0>] (schedule_timeout) from [<c01943a4>] (rcu_gp_kthread+0x49c/0x9f4)
> [ 24.349121] [<c01943a4>] (rcu_gp_kthread) from [<c01559f8>] (kthread+0x13c/0x148)
> [ 24.356658] [<c01559f8>] (kthread) from [<c01010e8>] (ret_from_fork+0x14/0x2c)
> [ 24.363922] Exception stack(0xe70a1fb0 to 0xe70a1ff8)
> [ 24.363922] 1fa0: 00000000 00000000 00000000 00000000
> [ 24.363922] 1fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
> [ 24.385437] 1fe0: 00000000 00000000 00000000 00000000 00000013 00000000
> [ 24.392089] NMI backtrace for cpu 0
> [ 24.392120] CPU: 0 PID: 105 Comm: kworker/0:2 Not tainted 5.3.0-rc3-arm #152
> [ 24.392120] Hardware name: Generic OMAP4 (Flattened Device Tree)
> [ 24.408721] Workqueue: events deferred_probe_work_func
> [ 24.408721] [<c010fd70>] (unwind_backtrace) from [<c010b7e8>] (show_stack+0x10/0x14)
> [ 24.421783] [<c010b7e8>] (show_stack) from [<c09a054c>] (dump_stack+0x84/0x9c)
> [ 24.429077] [<c09a054c>] (dump_stack) from [<c09a6ecc>] (nmi_cpu_backtrace+0x8c/0xc0)
> [ 24.436950] [<c09a6ecc>] (nmi_cpu_backtrace) from [<c09a7014>] (nmi_trigger_cpumask_backtrace+0x114/0x12c)
> [ 24.446655] [<c09a7014>] (nmi_trigger_cpumask_backtrace) from [<c01961e0>] (rcu_dump_cpu_stacks+0xa4/0xcc)
> [ 24.456359] [<c01961e0>] (rcu_dump_cpu_stacks) from [<c01952bc>] (rcu_sched_clock_irq+0x608/0x7f8)
> [ 24.465362] [<c01952bc>] (rcu_sched_clock_irq) from [<c019b21c>] (update_process_times+0x34/0x6c)
> [ 24.465362] [<c019b21c>] (update_process_times) from [<c01acfcc>] (tick_sched_timer+0x4c/0xa8)
> [ 24.483001] [<c01acfcc>] (tick_sched_timer) from [<c019c470>] (__hrtimer_run_queues+0x154/0x1fc)
> [ 24.491851] [<c019c470>] (__hrtimer_run_queues) from [<c019c84c>] (hrtimer_interrupt+0x11c/0x2ac)
> [ 24.500762] [<c019c84c>] (hrtimer_interrupt) from [<c010f3ac>] (twd_handler+0x30/0x38)
> [ 24.500762] [<c010f3ac>] (twd_handler) from [<c018959c>] (handle_percpu_devid_irq+0x78/0x138)
> [ 24.517333] [<c018959c>] (handle_percpu_devid_irq) from [<c0183a60>] (generic_handle_irq+0x24/0x34)
> [ 24.526458] [<c0183a60>] (generic_handle_irq) from [<c0184028>] (__handle_domain_irq+0x5c/0xb4)
> [ 24.526458] [<c0184028>] (__handle_domain_irq) from [<c03bbf2c>] (gic_handle_irq+0x58/0x9c)
> [ 24.526458] [<c03bbf2c>] (gic_handle_irq) from [<c0101a8c>] (__irq_svc+0x6c/0x90)
> [ 24.526458] Exception stack(0xe6439d68 to 0xe6439db0)
> [ 24.551177] 9d60: c0f783e8 00000000 00000000 efdb49d0 e647f2e8 efdb7f74
> [ 24.551177] 9d80: e647f2e8 00000000 e647f294 e647f2e8 00000000 efdb5a98 00000000 e6439db8
> [ 24.551177] 9da0: c04e9830 c04e9858 20000153 ffffffff
> [ 24.577789] [<c0101a8c>] (__irq_svc) from [<c04e9858>] (of_drm_find_bridge+0x40/0x84)
> [ 24.577789] [<c04e9858>] (of_drm_find_bridge) from [<c0526608>] (omapdss_device_init_output+0x38/0x140)
> [ 24.595153] [<c0526608>] (omapdss_device_init_output) from [<c0530294>] (dpi_init_port+0x208/0x294)
> [ 24.604248] [<c0530294>] (dpi_init_port) from [<c05278c4>] (dss_probe+0x2b4/0x550)
> [ 24.604248] [<c05278c4>] (dss_probe) from [<c0576c1c>] (platform_drv_probe+0x48/0x98)
> [ 24.604248] [<c0576c1c>] (platform_drv_probe) from [<c0574eb0>] (really_probe+0xf0/0x2c4)
> [ 24.627990] [<c0574eb0>] (really_probe) from [<c057520c>] (driver_probe_device+0x60/0x168)
> [ 24.627990] [<c057520c>] (driver_probe_device) from [<c0573410>] (bus_for_each_drv+0x84/0xc8)
> [ 24.644866] [<c0573410>] (bus_for_each_drv) from [<c0574d4c>] (__device_attach+0xd4/0x140)
> [ 24.644866] [<c0574d4c>] (__device_attach) from [<c05740f8>] (bus_probe_device+0x84/0x8c)
> [ 24.661376] [<c05740f8>] (bus_probe_device) from [<c057456c>] (deferred_probe_work_func+0x64/0x90)
> [ 24.670379] [<c057456c>] (deferred_probe_work_func) from [<c014f960>] (process_one_work+0x204/0x41c)
> [ 24.670410] [<c014f960>] (process_one_work) from [<c01510d4>] (worker_thread+0x2a8/0x5bc)
> [ 24.687805] [<c01510d4>] (worker_thread) from [<c01559f8>] (kthread+0x13c/0x148)
> [ 24.687805] [<c01559f8>] (kthread) from [<c01010e8>] (ret_from_fork+0x14/0x2c)
> [ 24.702484] Exception stack(0xe6439fb0 to 0xe6439ff8)
> [ 24.702484] 9fa0: 00000000 00000000 00000000 00000000
> [ 24.702484] 9fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
> [ 24.723999] 9fe0: 00000000 00000000 00000000 00000000 00000013 00000000
>
> I can send my .config upon request if needed.
>
> CONFIG_OMAP2_DSS_DPI is 'y', but there is nothing connected to the DPI port.
I've retested this on my pandaboard and couldn't reproduce the issue. As
I suspected a problem related to the kernel configuration, I tried
building the drivers in the kernel image instead of using modules, and I
then got a similar looking crash. I'm investigating it now.
> On 8/20/19 3:17 AM, Laurent Pinchart wrote:
> > In order to integrate with a chain of drm_bridge, the internal DPI
> > output has to expose its operations through the drm_bridge API.
> > Register a bridge at initialisation time to do so and remove the
> > omap_dss_device operations that are now unused.
> >
> > Signed-off-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
> > ---
> > drivers/gpu/drm/omapdrm/dss/dpi.c | 205 ++++++++++++++++++------------
> > 1 file changed, 122 insertions(+), 83 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/omapdrm/dss/dpi.c b/drivers/gpu/drm/omapdrm/dss/dpi.c
> > index c167bd1116ec..3874e6b6ec49 100644
> > --- a/drivers/gpu/drm/omapdrm/dss/dpi.c
> > +++ b/drivers/gpu/drm/omapdrm/dss/dpi.c
> > @@ -21,6 +21,8 @@
> > #include <linux/string.h>
> > #include <linux/sys_soc.h>
> >
> > +#include <drm/drm_bridge.h>
> > +
> > #include "dss.h"
> > #include "omapdss.h"
> >
> > @@ -41,12 +43,10 @@ struct dpi_data {
> > int data_lines;
> >
> > struct omap_dss_device output;
> > + struct drm_bridge bridge;
> > };
> >
> > -static struct dpi_data *dpi_get_data_from_dssdev(struct omap_dss_device *dssdev)
> > -{
> > - return container_of(dssdev, struct dpi_data, output);
> > -}
> > +#define drm_bridge_to_dpi(bridge) container_of(bridge, struct dpi_data, bridge)
> >
> > /* -----------------------------------------------------------------------------
> > * Clock Handling and PLL
> > @@ -354,6 +354,32 @@ static void dpi_config_lcd_manager(struct dpi_data *dpi)
> > dss_mgr_set_lcd_config(&dpi->output, &dpi->mgr_config);
> > }
> >
> > +static int dpi_clock_update(struct dpi_data *dpi, unsigned long *clock)
> > +{
> > + int lck_div, pck_div;
> > + unsigned long fck;
> > + struct dpi_clk_calc_ctx ctx;
> > +
> > + if (dpi->pll) {
> > + if (!dpi_pll_clk_calc(dpi, *clock, &ctx))
> > + return -EINVAL;
> > +
> > + fck = ctx.pll_cinfo.clkout[ctx.clkout_idx];
> > + } else {
> > + if (!dpi_dss_clk_calc(dpi, *clock, &ctx))
> > + return -EINVAL;
> > +
> > + fck = ctx.fck;
> > + }
> > +
> > + lck_div = ctx.dispc_cinfo.lck_div;
> > + pck_div = ctx.dispc_cinfo.pck_div;
> > +
> > + *clock = fck / lck_div / pck_div;
> > +
> > + return 0;
> > +}
> > +
> > static int dpi_verify_pll(struct dss_pll *pll)
> > {
> > int r;
> > @@ -391,29 +417,76 @@ static void dpi_init_pll(struct dpi_data *dpi)
> > }
> >
> > /* -----------------------------------------------------------------------------
> > - * omap_dss_device Operations
> > + * DRM Bridge Operations
> > */
> >
> > -static int dpi_connect(struct omap_dss_device *src,
> > - struct omap_dss_device *dst)
> > +static int dpi_bridge_attach(struct drm_bridge *bridge,
> > + enum drm_bridge_attach_flags flags)
> > {
> > - struct dpi_data *dpi = dpi_get_data_from_dssdev(dst);
> > + struct dpi_data *dpi = drm_bridge_to_dpi(bridge);
> > +
> > + if (!(flags & DRM_BRIDGE_ATTACH_NO_CONNECTOR))
> > + return -EINVAL;
> >
> > dpi_init_pll(dpi);
> >
> > - return omapdss_device_connect(dst->dss, dst, dst->next);
> > + return drm_bridge_attach(bridge->encoder, dpi->output.next_bridge,
> > + bridge, flags);
> > }
> >
> > -static void dpi_disconnect(struct omap_dss_device *src,
> > - struct omap_dss_device *dst)
> > +static enum drm_mode_status
> > +dpi_bridge_mode_valid(struct drm_bridge *bridge,
> > + const struct drm_display_mode *mode)
> > {
> > - omapdss_device_disconnect(dst, dst->next);
> > + struct dpi_data *dpi = drm_bridge_to_dpi(bridge);
> > + unsigned long clock = mode->clock * 1000;
> > + int ret;
> > +
> > + if (mode->hdisplay % 8 != 0)
> > + return MODE_BAD_WIDTH;
> > +
> > + if (mode->clock == 0)
> > + return MODE_NOCLOCK;
> > +
> > + ret = dpi_clock_update(dpi, &clock);
> > + if (ret < 0)
> > + return MODE_CLOCK_RANGE;
> > +
> > + return MODE_OK;
> > +}
> > +
> > +static bool dpi_bridge_mode_fixup(struct drm_bridge *bridge,
> > + const struct drm_display_mode *mode,
> > + struct drm_display_mode *adjusted_mode)
> > +{
> > + struct dpi_data *dpi = drm_bridge_to_dpi(bridge);
> > + unsigned long clock = mode->clock * 1000;
> > + int ret;
> > +
> > + ret = dpi_clock_update(dpi, &clock);
> > + if (ret < 0)
> > + return false;
> > +
> > + adjusted_mode->clock = clock / 1000;
> > +
> > + return true;
> > +}
> > +
> > +static void dpi_bridge_mode_set(struct drm_bridge *bridge,
> > + const struct drm_display_mode *mode,
> > + const struct drm_display_mode *adjusted_mode)
> > +{
> > + struct dpi_data *dpi = drm_bridge_to_dpi(bridge);
> > +
> > + mutex_lock(&dpi->lock);
> > + dpi->pixelclock = adjusted_mode->clock * 1000;
> > + mutex_unlock(&dpi->lock);
> > }
> >
> > -static void dpi_display_enable(struct omap_dss_device *dssdev)
> > +static void dpi_bridge_enable(struct drm_bridge *bridge,
> > + struct drm_atomic_state *state)
> > {
> > - struct dpi_data *dpi = dpi_get_data_from_dssdev(dssdev);
> > - struct omap_dss_device *out = &dpi->output;
> > + struct dpi_data *dpi = drm_bridge_to_dpi(bridge);
> > int r;
> >
> > mutex_lock(&dpi->lock);
> > @@ -428,7 +501,7 @@ static void dpi_display_enable(struct omap_dss_device *dssdev)
> > if (r)
> > goto err_get_dispc;
> >
> > - r = dss_dpi_select_source(dpi->dss, dpi->id, out->dispc_channel);
> > + r = dss_dpi_select_source(dpi->dss, dpi->id, dpi->output.dispc_channel);
> > if (r)
> > goto err_src_sel;
> >
> > @@ -468,9 +541,10 @@ static void dpi_display_enable(struct omap_dss_device *dssdev)
> > mutex_unlock(&dpi->lock);
> > }
> >
> > -static void dpi_display_disable(struct omap_dss_device *dssdev)
> > +static void dpi_bridge_disable(struct drm_bridge *bridge,
> > + struct drm_atomic_state *state)
> > {
> > - struct dpi_data *dpi = dpi_get_data_from_dssdev(dssdev);
> > + struct dpi_data *dpi = drm_bridge_to_dpi(bridge);
> >
> > mutex_lock(&dpi->lock);
> >
> > @@ -490,71 +564,33 @@ static void dpi_display_disable(struct omap_dss_device *dssdev)
> > mutex_unlock(&dpi->lock);
> > }
> >
> > -static int dpi_check_timings(struct omap_dss_device *dssdev,
> > - struct drm_display_mode *mode)
> > -{
> > - struct dpi_data *dpi = dpi_get_data_from_dssdev(dssdev);
> > - int lck_div, pck_div;
> > - unsigned long fck;
> > - unsigned long pck;
> > - struct dpi_clk_calc_ctx ctx;
> > - bool ok;
> > -
> > - if (mode->hdisplay % 8 != 0)
> > - return -EINVAL;
> > -
> > - if (mode->clock == 0)
> > - return -EINVAL;
> > -
> > - if (dpi->pll) {
> > - ok = dpi_pll_clk_calc(dpi, mode->clock * 1000, &ctx);
> > - if (!ok)
> > - return -EINVAL;
> > -
> > - fck = ctx.pll_cinfo.clkout[ctx.clkout_idx];
> > - } else {
> > - ok = dpi_dss_clk_calc(dpi, mode->clock * 1000, &ctx);
> > - if (!ok)
> > - return -EINVAL;
> > -
> > - fck = ctx.fck;
> > - }
> > -
> > - lck_div = ctx.dispc_cinfo.lck_div;
> > - pck_div = ctx.dispc_cinfo.pck_div;
> > -
> > - pck = fck / lck_div / pck_div;
> > -
> > - mode->clock = pck / 1000;
> > -
> > - return 0;
> > -}
> > -
> > -static void dpi_set_timings(struct omap_dss_device *dssdev,
> > - const struct drm_display_mode *mode)
> > -{
> > - struct dpi_data *dpi = dpi_get_data_from_dssdev(dssdev);
> > -
> > - DSSDBG("dpi_set_timings\n");
> > -
> > - mutex_lock(&dpi->lock);
> > -
> > - dpi->pixelclock = mode->clock * 1000;
> > -
> > - mutex_unlock(&dpi->lock);
> > -}
> > -
> > -static const struct omap_dss_device_ops dpi_ops = {
> > - .connect = dpi_connect,
> > - .disconnect = dpi_disconnect,
> > -
> > - .enable = dpi_display_enable,
> > - .disable = dpi_display_disable,
> > -
> > - .check_timings = dpi_check_timings,
> > - .set_timings = dpi_set_timings,
> > +static const struct drm_bridge_funcs dpi_bridge_funcs = {
> > + .attach = dpi_bridge_attach,
> > + .mode_valid = dpi_bridge_mode_valid,
> > + .mode_fixup = dpi_bridge_mode_fixup,
> > + .mode_set = dpi_bridge_mode_set,
> > + .atomic_enable = dpi_bridge_enable,
> > + .atomic_disable = dpi_bridge_disable,
> > };
> >
> > +static void dpi_bridge_init(struct dpi_data *dpi)
> > +{
> > + dpi->bridge.funcs = &dpi_bridge_funcs;
> > + dpi->bridge.of_node = dpi->pdev->dev.of_node;
> > + dpi->bridge.type = DRM_MODE_CONNECTOR_DPI;
> > +
> > + drm_bridge_add(&dpi->bridge);
> > +}
> > +
> > +static void dpi_bridge_cleanup(struct dpi_data *dpi)
> > +{
> > + drm_bridge_remove(&dpi->bridge);
> > +}
> > +
> > +/* -----------------------------------------------------------------------------
> > + * Initialisation and Cleanup
> > + */
> > +
> > /*
> > * Return a hardcoded channel for the DPI output. This should work for
> > * current use cases, but this can be later expanded to either resolve
> > @@ -597,6 +633,8 @@ static int dpi_init_output_port(struct dpi_data *dpi, struct device_node *port)
> > u32 port_num = 0;
> > int r;
> >
> > + dpi_bridge_init(dpi);
> > +
> > of_property_read_u32(port, "reg", &port_num);
> > dpi->id = port_num <= 2 ? port_num : 0;
> >
> > @@ -618,10 +656,9 @@ static int dpi_init_output_port(struct dpi_data *dpi, struct device_node *port)
> > out->type = OMAP_DISPLAY_TYPE_DPI;
> > out->dispc_channel = dpi_get_channel(dpi);
> > out->of_port = port_num;
> > - out->ops = &dpi_ops;
> > out->owner = THIS_MODULE;
> >
> > - r = omapdss_device_init_output(out, NULL);
> > + r = omapdss_device_init_output(out, &dpi->bridge);
> > if (r < 0)
> > return r;
> >
> > @@ -637,6 +674,8 @@ static void dpi_uninit_output_port(struct device_node *port)
> >
> > omapdss_device_unregister(out);
> > omapdss_device_cleanup_output(out);
> > +
> > + dpi_bridge_cleanup(dpi);
> > }
> >
> > /* -----------------------------------------------------------------------------
> >
>
--
Regards,
Laurent Pinchart
_______________________________________________
dri-devel mailing list
dri-devel@xxxxxxxxxxxxxxxxxxxxx
https://lists.freedesktop.org/mailman/listinfo/dri-devel
