If ret isn't zero, it is almost for sure ETIMEDOUT, because
we use it in wait_for macro which does continuous retries
until timeout is reached. If we still ran out of time and
retries, we most likely would be interested in getting status,
to understand what was the actual error propagated from PCode,
rather than to find out that we had a time out, which is anyway
quite obvious, if the function fails.
v2: Make it status ? status : ret(thanks Vinod for the hint)
Signed-off-by: Stanislav Lisovskiy <stanislav.lisovskiy@intel.com>
Reviewed-by: Vinod Govindapillai <vinod.govindapillai@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220411081343.18099-1-stanislav.lisovskiy@intel.com
Currently skl_pcode_try_request function doesn't
properly handle return value it gets from
snb_pcode_rw, but treats status != 0 as success,
returning true, which basically doesn't allow
to use retry/timeout mechanisms if PCode happens
to be busy and returns EGAIN or some other status
code not equal to 0.
We saw this on real hw and also tried simulating this
by always returning -EAGAIN from snb_pcode_rw for 6 times, which
currently will just result in false success, while it should
have tried until timeout is reached:
[ 22.357729] i915 0000:00:02.0: [drm:intel_cdclk_dump_config [i915]] Changing CDCLK to
307200 kHz, VCO 614400 kHz, ref 38400 kHz, bypass 19200 kHz, voltage level 0
[ 22.357831] i915 0000:00:02.0: [drm:__snb_pcode_rw [i915]] Returning EAGAIN retry 1
[ 22.357892] i915 0000:00:02.0: [drm:skl_pcode_request [i915]] Success, exiting
[ 22.357936] i915 0000:00:02.0: [drm] ERROR Failed to inform PCU about cdclk change (err -11, freq 307200)
We see en error because higher level api, still notices that status was wrong,
however we still did try only once.
We fix it by requiring _both_ the status to be 0 and
request/reply match for success(true) and function
should return failure(false) if either status turns
out to be EAGAIN, EBUSY or whatever or reply/request
masks do not match.
So now we see this in the logs:
[ 22.318667] i915 0000:00:02.0: [drm:intel_cdclk_dump_config [i915]] Changing CDCLK to
307200 kHz, VCO 614400 kHz, ref 38400 kHz, bypass 19200 kHz, voltage level 0
[ 22.318782] i915 0000:00:02.0: [drm:__snb_pcode_rw [i915]] Returning EAGAIN retry 1
[ 22.318849] i915 0000:00:02.0: [drm:__snb_pcode_rw [i915]] Returning EAGAIN retry 2
[ 22.319006] i915 0000:00:02.0: [drm:__snb_pcode_rw [i915]] Returning EAGAIN retry 3
[ 22.319091] i915 0000:00:02.0: [drm:__snb_pcode_rw [i915]] Returning EAGAIN retry 4
[ 22.319158] i915 0000:00:02.0: [drm:__snb_pcode_rw [i915]] Returning EAGAIN retry 5
[ 22.319224] i915 0000:00:02.0: [drm:__snb_pcode_rw [i915]] Returning EAGAIN retry 6
Reviewed-by: Vinod Govindapillai <vinod.govindapillai@intel.com>
Signed-off-by: Stanislav Lisovskiy <stanislav.lisovskiy@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220408125200.9069-2-stanislav.lisovskiy@intel.com
Several of our i915 header files, have been including i915_reg.h. This
means that any change to i915_reg.h will trigger a full rebuild of
pretty much every file of the driver, even those that don't have any
kind of register access. Let's delete the i915_reg.h include from all
headers and add an explicit include from the .c files that truly
need the register definitions; those that need a definition of
i915_reg_t for a function definition can get it from i915_reg_defs.h
instead.
We also remove two non-register #define's (VLV_DISPLAY_BASE and
GEN12_SFC_DONE_MAX) into i915_reg_defs.h to allow us to drop the
i915_reg.h include from a couple of headers.
There's probably a lot more header dependency optimization possible, but
the changes here roughly cut the number of files compiled after 'touch
i915_reg.h' in half --- a good first step.
Cc: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Reviewed-by: Lucas De Marchi <lucas.demarchi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220127234334.4016964-7-matthew.d.roper@intel.com
The snb+ pcode mailbox code is not sideband, so split it out to a
separate file. As can be seen from the #include changes, very few places
use both sideband and pcode.
Code movement only.
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Lucas De Marchi <lucas.demarchi@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/185deb18eb739e5ae019e27834b9997dcc1347bc.1634207064.git.jani.nikula@intel.com
