drm/i915: FPGA_DBG is display-specific
Although the bspec's description doesn't make it very clear, the hardware architects have confirmed that the FPGA_DBG register that we use to check for unclaimed MMIO accesses is display-specific and will only properly flag unclaimed MMIO transactions for registers in the display range. If a platform doesn't have display, FPGA_DBG itself will not be available and should not be checked. Let's move the feature flag into intel_device_info.display to more accurately reflect this. Given that we now know FPGA_DBG is display-specific, it could be argued that we should only check it on out intel_de_*() functions. However let's not make that change right now; keeping the checks in all of the existing locations still helps us catch cases where regular intel_uncore_*() functions use bad MMIO offset math / base addresses and accidentally wind up landing within an unused area within the display MMIO range. It will also help catch cases where userspace-initiated MMIO (e.g., IGT's intel_reg tool) attempt to read bad offsets within the display range. v2: Add missing hunk with the update to the HAS_FPGA_DBG_UNCLAIMED macro. (CI) Cc: Lucas De Marchi <lucas.demarchi@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/20210212222049.3516344-1-matthew.d.roper@intel.com
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