docs/envvars: document MESA_VK_WSI_PRESENT_MODE

This env var was introduced in a182adfd83ad ("wsi: allow to override the
present mode with MESA_VK_WSI_PRESENT_MODE").

Signed-off-by: Simon Ser <contact@emersion.fr>
Reviewed-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>
Reviewed-by: Adam Jackson <ajax@redhat.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/11441>

diff --git a/docs/envvars.rst b/docs/envvars.rst
index a3b2e7e..d8b0ac2 100644 (file)
--- a/docs/envvars.rst
+++ b/docs/envvars.rst
@@ -184,6 +184,10 @@ Core Mesa environment variables
       instance version as advertised by ``vkEnumerateInstanceVersion``
    -  This can be very useful for debugging but some features may not be
       implemented correctly. (For developers only)
+:envvar:`MESA_VK_WSI_PRESENT_MODE`
+   overrides the WSI present mode clients specify in
+   ``VkSwapchainCreateInfoKHR::presentMode``. Values can be ``fifo``,
+   ``relaxed``, ``mailbox`` or ``immediate``.
 :envvar:`MESA_LOADER_DRIVER_OVERRIDE`
    chooses a different driver binary such as ``etnaviv`` or ``zink``.