[Intel-gfx] [PATCH v2 1/1] drm/i915: Do RPM Wake during GuC/HuC status read

[Kamble, Sagar A]

On 2/4/2017 7:40 PM, Arkadiusz Hiler wrote:
> On Fri, Feb 03, 2017 at 01:58:33PM +0530, Sagar Arun Kamble wrote:
>> HUC_STATUS, GUC_STATUS, SOFT_SCRATCH registers are read in debugfs
>> and getparam ioctl. This patch covers those accesses by RPM get/put.
>>
>> v2: Covering access in i915_getparam(I915_PARAM_HUC_STATUS) (ChrisW)
>>
>> Cc: Arkadiusz Hiler <arkadiusz.hiler at intel.com>
>> Cc: Anusha Srivatsa <anusha.srivatsa at intel.com>
>> Cc: Fiedorowicz, Lukasz <lukasz.fiedorowicz at intel.com>
>> Signed-off-by: Sagar Arun Kamble <sagar.a.kamble at intel.com>
>> ---
>>   drivers/gpu/drm/i915/i915_debugfs.c | 6 ++++++
>>   drivers/gpu/drm/i915/i915_drv.c     | 5 ++---
>>   2 files changed, 8 insertions(+), 3 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c
>> index 3ae0656..639ed12 100644
>> --- a/drivers/gpu/drm/i915/i915_debugfs.c
>> +++ b/drivers/gpu/drm/i915/i915_debugfs.c
>> @@ -2374,7 +2374,9 @@ static int i915_huc_load_status_info(struct seq_file *m, void *data)
>>   	seq_printf(m, "\tRSA: offset is %d; size = %d\n",
>>   		huc_fw->rsa_offset, huc_fw->rsa_size);
>>   
>> +	intel_runtime_pm_get(dev_priv);
>>   	seq_printf(m, "\nHuC status 0x%08x:\n", I915_READ(HUC_STATUS2));
>> +	intel_runtime_pm_put(dev_priv);
>>   
>>   	return 0;
>>   }
> Are you sure that HUC_STATUS2 requires RPM get for reading?
>
> I remember trying reading it with device forcefully asleep and it
> succeed just fine.
Hi Arek,

Faced following warning with device runtime_status=suspended.
Also this register lies in media forcewake range and should have similar 
RPM get/put needs as other registers unless this has special behavior I 
am not aware of.

[  153.923576] WARNING: CPU: 1 PID: 1859 at 
drivers/gpu/drm/i915/intel_drv.h:1698 gen9_decoupled_read32+0x1a1/0x1c0 
[i915]
[  153.923578] Device suspended during HW access
[  153.923580] Modules linked in: spi_pxa2xx_platform 8250_dw 
i2c_designware_platform i2c_designware_core intel_rapl 
intel_telemetry_debugfs intel_telemetry_pltdrv intel_punit_ipc 
intel_telemetry_core x86_pkg_temp_thermal binfmt_misc coretemp kvm_intel 
snd_soc_skl kvm snd_soc_rt298 snd_soc_skl_ipc snd_soc_rt286 
snd_soc_sst_ipc snd_soc_rl6347a snd_soc_sst_dsp snd_hda_ext_core 
snd_soc_sst_match irqbypass nls_iso8859_1 crct10dif_pclmul crc32_pclmul 
ghash_clmulni_intel pcbc snd_hda_codec_hdmi snd_hda_intel snd_hda_codec 
snd_hda_core snd_soc_core snd_hwdep aesni_intel snd_compress aes_x86_64 
ac97_bus crypto_simd snd_pcm_dmaengine glue_helper cryptd snd_pcm 
intel_rapl_perf snd_seq_midi snd_seq_midi_event wdat_wdt snd_rawmidi 
input_leds serio_raw snd_seq pwm_lpss_pci pwm_lpss snd_seq_device 
snd_timer idma64
[  153.923671]  virt_dma intel_lpss_pci intel_lpss snd 
hid_sensor_accel_3d hid_sensor_magn_3d hid_sensor_als hid_sensor_gyro_3d 
hid_sensor_incl_3d hid_sensor_rotation hid_sensor_press 
hid_sensor_trigger mei_me industrialio_triggered_buffer kfifo_buf 
hid_sensor_iio_common industrialio mei soundcore shpchp rfkill_gpio 
soc_button_array intel_vbtn tpm_crb ucsi intel_hid intel_pmc_ipc 
sparse_keymap mac_hid autofs4 hid_generic usbhid hid_sensor_custom 
hid_sensor_hub intel_ishtp_hid i915(E) drm_kms_helper syscopyarea 
psmouse igb sysfillrect sdhci_pci sysimgblt fb_sys_fops sdhci dca ptp 
drm pps_core ahci intel_ish_ipc i2c_algo_bit libahci intel_ishtp i2c_hid 
hid video fjes pinctrl_broxton pinctrl_intel
[  153.923768] CPU: 1 PID: 1859 Comm: cat Tainted: G     U  W   E 
4.10.0-rc6-ww5.5mainlinestaging #12
[  153.923771] Hardware name: Intel Corp. Broxton P/Apollolake RVP1C, 
BIOS APLIRVPA.X64.0151.B24.1609210905 09/21/2016
[  153.923773] Call Trace:
[  153.923785]  dump_stack+0x63/0x90
[  153.923791]  __warn+0xd1/0xf0
[  153.923795]  warn_slowpath_fmt+0x4f/0x60
[  153.923803]  ? seq_vprintf+0x35/0x50
[  153.923893]  gen9_decoupled_read32+0x1a1/0x1c0 [i915]
[  153.923969]  i915_huc_load_status_info+0x132/0x150 [i915]
[  153.923974]  seq_read+0x119/0x3e0
[  153.923981]  full_proxy_read+0x51/0x80
[  153.923988]  __vfs_read+0x28/0x130
[  153.923993]  ? security_file_permission+0x9d/0xc0
[  153.923998]  ? rw_verify_area+0x4e/0xb0
[  153.924003]  vfs_read+0x93/0x130
[  153.924009]  SyS_read+0x46/0xa0
[  153.924015]  entry_SYSCALL_64_fastpath+0x1e/0xad
[  153.924019] RIP: 0033:0x7fe18cd44680
[  153.924022] RSP: 002b:00007ffe7d991eb8 EFLAGS: 00000246 ORIG_RAX: 
0000000000000000
[  153.924027] RAX: ffffffffffffffda RBX: 00007fe18d011b20 RCX: 
00007fe18cd44680
[  153.924030] RDX: 0000000000020000 RSI: 00007fe18d1fb000 RDI: 
0000000000000003
[  153.924032] RBP: 0000000000021010 R08: ffffffffffffffff R09: 
0000000000000000
[  153.924035] R10: 000000000000037b R11: 0000000000000246 R12: 
0000000000022000
[  153.924037] R13: 00007fe18d011b78 R14: 0000000000001000 R15: 
0000000000020000
[  153.924042] ---[ end trace 6529f5b46f5753d0 ]---
[  153.974135] [drm:__gen9_decoupled_mmio_access [i915]] *ERROR* 
Decoupled MMIO wait timed out

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