Hi Saravana, On 15.05.2020 07:35, Saravana Kannan wrote: > The fw_devlink_pause() and fw_devlink_resume() APIs allow batching the > parsing of the device tree nodes when a lot of devices are added. This > will significantly cut down parsing time (as much a 1 second on some > systems). So, use them when adding devices for all the top level device > tree nodes in a system. > > Signed-off-by: Saravana Kannan <saravanak@xxxxxxxxxx> This patch recently landed in linux-next 20200518. Sadly, it causes regression on Samsung Exynos5433-based TM2e board: s3c64xx-spi 14d30000.spi: Failed to get RX DMA channel s3c64xx-spi 14d50000.spi: Failed to get RX DMA channel s3c64xx-spi 14d30000.spi: Failed to get RX DMA channel s3c64xx-spi 14d50000.spi: Failed to get RX DMA channel s3c64xx-spi 14d30000.spi: Failed to get RX DMA channel Internal error: synchronous external abort: 96000210 [#1] PREEMPT SMP Modules linked in: CPU: 0 PID: 50 Comm: kworker/0:1 Not tainted 5.7.0-rc5+ #701 Hardware name: Samsung TM2E board (DT) Workqueue: events deferred_probe_work_func pstate: 60000005 (nZCv daif -PAN -UAO) pc : samsung_i2s_probe+0x768/0x8f0 lr : samsung_i2s_probe+0x688/0x8f0 ... Call trace: samsung_i2s_probe+0x768/0x8f0 platform_drv_probe+0x50/0xa8 really_probe+0x108/0x370 driver_probe_device+0x54/0xb8 __device_attach_driver+0x90/0xc0 bus_for_each_drv+0x70/0xc8 __device_attach+0xdc/0x140 device_initial_probe+0x10/0x18 bus_probe_device+0x94/0xa0 deferred_probe_work_func+0x70/0xa8 process_one_work+0x2a8/0x718 worker_thread+0x48/0x470 kthread+0x134/0x160 ret_from_fork+0x10/0x1c Code: 17ffffaf d503201f f94086c0 91003000 (88dffc00) ---[ end trace ccf721c9400ddbd6 ]--- Kernel panic - not syncing: Fatal exception SMP: stopping secondary CPUs Kernel Offset: disabled CPU features: 0x090002,24006087 Memory Limit: none ---[ end Kernel panic - not syncing: Fatal exception ]--- Both issues, the lack of DMA for SPI device and Synchronous abort in I2S probe are new after applying this patch. I'm trying to investigate which resources are missing and why. The latter issue means typically that the registers for the given device has been accessed without enabling the needed clocks or power domains. > --- > drivers/of/platform.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/drivers/of/platform.c b/drivers/of/platform.c > index 3371e4a06248..55d719347810 100644 > --- a/drivers/of/platform.c > +++ b/drivers/of/platform.c > @@ -538,7 +538,9 @@ static int __init of_platform_default_populate_init(void) > } > > /* Populate everything else. */ > + fw_devlink_pause(); > of_platform_default_populate(NULL, NULL, NULL); > + fw_devlink_resume(); > > return 0; > } Best regards -- Marek Szyprowski, PhD Samsung R&D Institute Poland
