From b2e7723b09eb059584943febf47d637b2b8ca73f Mon Sep 17 00:00:00 2001 From: Matt Roper Date: Thu, 22 Jan 2015 16:53:12 -0800 Subject: [PATCH] drm/i915: Add i915.nuclear_pageflip command line param to force atomic (v4) We don't have full atomic modeset support yet, but the "nuclear pageflip" subset of functionality (i.e., plane operations only) should be ready. Allow the user to force atomic on for debug purposes, or for fixed-purpose embedded devices that will only use atomic for plane updates. The term 'nuclear' is used here instead of 'atomic' to make it clear that this doesn't allow full atomic modeset support, just a (very useful) subset of the atomic functionality. We'll drop the kernel parameter and unconditionally enable atomic in a future patch once all of the necessary pieces are in. v2: - Use module_param_named_unsafe() (Daniel) - Simplify comment on DRIVER_ATOMIC guard (Daniel) v3: - Make the parameter "nuclear_pageflip" rather than just "nuclear" for clarity. (Ander) v4: - Make the internal variable "nuclear_pageflip" as well as the command-line option. (Ander) Signed-off-by: Matt Roper Reviewed-by: Ander Conselvan de Oliveira Signed-off-by: Daniel Vetter --- drivers/gpu/drm/i915/i915_drv.c | 8 ++++++++ drivers/gpu/drm/i915/i915_drv.h | 1 + drivers/gpu/drm/i915/i915_params.c | 5 +++++ 3 files changed, 14 insertions(+) diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c index 6484229dd10d..9da4e60bdc7a 100644 --- a/drivers/gpu/drm/i915/i915_drv.c +++ b/drivers/gpu/drm/i915/i915_drv.c @@ -1643,6 +1643,14 @@ static int __init i915_init(void) #endif } + /* + * FIXME: Note that we're lying to the DRM core here so that we can get access + * to the atomic ioctl and the atomic properties. Only plane operations on + * a single CRTC will actually work. + */ + if (i915.nuclear_pageflip) + driver.driver_features |= DRIVER_ATOMIC; + return drm_pci_init(&driver, &i915_pci_driver); } diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h index 3e81d9aaa50a..760d239a73f3 100644 --- a/drivers/gpu/drm/i915/i915_drv.h +++ b/drivers/gpu/drm/i915/i915_drv.h @@ -2527,6 +2527,7 @@ struct i915_params { int use_mmio_flip; bool mmio_debug; bool verbose_state_checks; + bool nuclear_pageflip; }; extern struct i915_params i915 __read_mostly; diff --git a/drivers/gpu/drm/i915/i915_params.c b/drivers/gpu/drm/i915/i915_params.c index 07252d8dc726..44f2262a5553 100644 --- a/drivers/gpu/drm/i915/i915_params.c +++ b/drivers/gpu/drm/i915/i915_params.c @@ -52,6 +52,7 @@ struct i915_params i915 __read_mostly = { .use_mmio_flip = 0, .mmio_debug = 0, .verbose_state_checks = 1, + .nuclear_pageflip = 0, }; module_param_named(modeset, i915.modeset, int, 0400); @@ -178,3 +179,7 @@ MODULE_PARM_DESC(mmio_debug, module_param_named(verbose_state_checks, i915.verbose_state_checks, bool, 0600); MODULE_PARM_DESC(verbose_state_checks, "Enable verbose logs (ie. WARN_ON()) in case of unexpected hw state conditions."); + +module_param_named_unsafe(nuclear_pageflip, i915.nuclear_pageflip, bool, 0600); +MODULE_PARM_DESC(nuclear_pageflip, + "Force atomic modeset functionality; only planes work for now (default: false)."); -- 2.20.1