From ec112a35e27ea8e7b4f294616e897671447e6086 Mon Sep 17 00:00:00 2001
From: Faith Ekstrand <faith.ekstrand@collabora.com>
Date: Mon, 25 Aug 2025 17:04:36 -0400
Subject: [PATCH] nak: Add a nak_qmd_size_B() query

Also add a #define NAK_QMD_ALIGN_B for alignments.  The alignment is
always 256B and there's no evidence of that changing.

Reviewed-by: Mel Henning <mhenning@darkrefraction.com>
Backport-to: 25.2
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/36995>
(cherry picked from commit 02ef6a51587b6a57039515c8b6dbc4f90cc94e2f)
---
 .pick_status.json                |  2 +-
 src/nouveau/compiler/meson.build |  1 +
 src/nouveau/compiler/nak.h       |  6 ++++++
 src/nouveau/compiler/nak/qmd.rs  | 21 +++++++++++++++++++++
 4 files changed, 29 insertions(+), 1 deletion(-)

diff --git a/.pick_status.json b/.pick_status.json
index ff1d529b52d..c58c0df6952 100644
--- a/.pick_status.json
+++ b/.pick_status.json
@@ -3954,7 +3954,7 @@
         "description": "nak: Add a nak_qmd_size_B() query",
         "nominated": true,
         "nomination_type": 4,
-        "resolution": 0,
+        "resolution": 1,
         "main_sha": null,
         "because_sha": null,
         "notes": null
diff --git a/src/nouveau/compiler/meson.build b/src/nouveau/compiler/meson.build
index 9d87a0d4aeb..0ca7dcd13e1 100644
--- a/src/nouveau/compiler/meson.build
+++ b/src/nouveau/compiler/meson.build
@@ -63,6 +63,7 @@ _nak_bindings_rs = rust.bindgen(
     '--allowlist-type', 'nak_.*',
     '--allowlist-type', 'nouveau_ws_.*',
     '--allowlist-var', 'DRM_.*',
+    '--allowlist-var', 'NAK_.*',
     '--allowlist-var', 'NVIDIA_VENDOR_ID',
     '--allowlist-function', 'drm.*',
     '--allowlist-function', 'nak_.*',
diff --git a/src/nouveau/compiler/nak.h b/src/nouveau/compiler/nak.h
index aa2c8628791..b43b0026e80 100644
--- a/src/nouveau/compiler/nak.h
+++ b/src/nouveau/compiler/nak.h
@@ -251,6 +251,12 @@ struct nak_qmd_info {
    struct nak_qmd_cbuf cbufs[8];
 };
 
+#define NAK_QMD_ALIGN_B 256
+#define NAK_MAX_QMD_SIZE_B 256
+#define NAK_MAX_QMD_DWORDS (NAK_MAX_QMD_SIZE_B / 4)
+
+uint32_t nak_qmd_size_B(const struct nv_device_info *dev);
+
 void nak_fill_qmd(const struct nv_device_info *dev,
                   const struct nak_shader_info *info,
                   const struct nak_qmd_info *qmd_info,
diff --git a/src/nouveau/compiler/nak/qmd.rs b/src/nouveau/compiler/nak/qmd.rs
index d437c34da93..e97c0a4fd73 100644
--- a/src/nouveau/compiler/nak/qmd.rs
+++ b/src/nouveau/compiler/nak/qmd.rs
@@ -580,6 +580,27 @@ fn fill_qmd<Q: QMD>(info: &nak_shader_info, qmd_info: &nak_qmd_info) -> Q {
     qmd
 }
 
+#[no_mangle]
+pub extern "C" fn nak_qmd_size_B(dev: &nv_device_info) -> u32 {
+    let size_B = if dev.cls_compute >= clcdc0::BLACKWELL_COMPUTE_A {
+        size_of::<Qmd5_0>().try_into().unwrap()
+    } else if dev.cls_compute >= clcbc0::HOPPER_COMPUTE_A {
+        size_of::<Qmd4_0>().try_into().unwrap()
+    } else if dev.cls_compute >= clc6c0::AMPERE_COMPUTE_A {
+        size_of::<Qmd3_0>().try_into().unwrap()
+    } else if dev.cls_compute >= clc3c0::VOLTA_COMPUTE_A {
+        size_of::<Qmd2_2>().try_into().unwrap()
+    } else if dev.cls_compute >= clc0c0::PASCAL_COMPUTE_A {
+        size_of::<Qmd2_1>().try_into().unwrap()
+    } else if dev.cls_compute >= cla0c0::KEPLER_COMPUTE_A {
+        size_of::<Qmd0_6>().try_into().unwrap()
+    } else {
+        panic!("Unknown shader model");
+    };
+    assert!(size_B <= NAK_MAX_QMD_SIZE_B);
+    size_B
+}
+
 #[no_mangle]
 pub extern "C" fn nak_fill_qmd(
     dev: *const nv_device_info,