[Intel-gfx] [PATCH v2 RESEND] drm/i915: add support for specifying DMC firmware override by module param

[David Weinehall]

On Tue, Apr 24, 2018 at 03:20:16PM +0300, Jani Nikula wrote:
> Use i915.dmc_firmware_path to override default firmware for the platform
> and bypassing version checks.
> 
> v2: add missing param struct member declaration (David)
> 
> Tested-by: David Weinehall <david.weinehall at linux.intel.com>
> Reviewed-by: David Weinehall <david.weinehall at linux.intel.com>

Re-tested against latest drm-tip; still works fine.

> Cc: Anusha Srivatsa <anusha.srivatsa at intel.com>
> Cc: David Weinehall <david.weinehall at linux.intel.com>
> Signed-off-by: Jani Nikula <jani.nikula at intel.com>
> ---
>  drivers/gpu/drm/i915/i915_params.c | 3 +++
>  drivers/gpu/drm/i915/i915_params.h | 1 +
>  drivers/gpu/drm/i915/intel_csr.c   | 9 +++++++--
>  3 files changed, 11 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/i915_params.c b/drivers/gpu/drm/i915/i915_params.c
> index 08108ce5be21..66ea3552c63e 100644
> --- a/drivers/gpu/drm/i915/i915_params.c
> +++ b/drivers/gpu/drm/i915/i915_params.c
> @@ -164,6 +164,9 @@ i915_param_named_unsafe(guc_firmware_path, charp, 0400,
>  i915_param_named_unsafe(huc_firmware_path, charp, 0400,
>  	"HuC firmware path to use instead of the default one");
>  
> +i915_param_named_unsafe(dmc_firmware_path, charp, 0400,
> +	"DMC firmware path to use instead of the default one");
> +
>  i915_param_named_unsafe(enable_dp_mst, bool, 0600,
>  	"Enable multi-stream transport (MST) for new DisplayPort sinks. (default: true)");
>  
> diff --git a/drivers/gpu/drm/i915/i915_params.h b/drivers/gpu/drm/i915/i915_params.h
> index c96360398072..6684025b7af8 100644
> --- a/drivers/gpu/drm/i915/i915_params.h
> +++ b/drivers/gpu/drm/i915/i915_params.h
> @@ -51,6 +51,7 @@ struct drm_printer;
>  	param(int, guc_log_level, -1) \
>  	param(char *, guc_firmware_path, NULL) \
>  	param(char *, huc_firmware_path, NULL) \
> +	param(char *, dmc_firmware_path, NULL) \
>  	param(int, mmio_debug, 0) \
>  	param(int, edp_vswing, 0) \
>  	param(int, reset, 2) \
> diff --git a/drivers/gpu/drm/i915/intel_csr.c b/drivers/gpu/drm/i915/intel_csr.c
> index 41e6c75a7f3c..d81673250d3b 100644
> --- a/drivers/gpu/drm/i915/intel_csr.c
> +++ b/drivers/gpu/drm/i915/intel_csr.c
> @@ -297,7 +297,10 @@ static uint32_t *parse_csr_fw(struct drm_i915_private *dev_priv,
>  
>  	csr->version = css_header->version;
>  
> -	if (IS_CANNONLAKE(dev_priv)) {
> +	if (csr->fw_path == i915_modparams.dmc_firmware_path) {
> +		/* Bypass version check for firmware override. */
> +		required_version = csr->version;
> +	} else if (IS_CANNONLAKE(dev_priv)) {
>  		required_version = CNL_CSR_VERSION_REQUIRED;
>  	} else if (IS_GEMINILAKE(dev_priv)) {
>  		required_version = GLK_CSR_VERSION_REQUIRED;
> @@ -452,7 +455,9 @@ void intel_csr_ucode_init(struct drm_i915_private *dev_priv)
>  	if (!HAS_CSR(dev_priv))
>  		return;
>  
> -	if (IS_CANNONLAKE(dev_priv))
> +	if (i915_modparams.dmc_firmware_path)
> +		csr->fw_path = i915_modparams.dmc_firmware_path;
> +	else if (IS_CANNONLAKE(dev_priv))
>  		csr->fw_path = I915_CSR_CNL;
>  	else if (IS_GEMINILAKE(dev_priv))
>  		csr->fw_path = I915_CSR_GLK;
> -- 
> 2.11.0
>