[PATCH v11 02/12] gpu: nova-core: falcon: add constant for memory block alignment

[Alexandre Courbot <acourbot@nvidia.com>]

Falcon memory blocks are 256 bytes in size. This is a hard constant on
all models.

This value was hardcoded, so turn it into a documented constant. It will
also become useful with the PIO loading code.

Reviewed-by: Eliot Courtney <ecourtney@nvidia.com>
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
---
 drivers/gpu/nova-core/falcon.rs | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/nova-core/falcon.rs b/drivers/gpu/nova-core/falcon.rs
index 8d444cf9d55c..31217cd3a795 100644
--- a/drivers/gpu/nova-core/falcon.rs
+++ b/drivers/gpu/nova-core/falcon.rs
@@ -25,6 +25,7 @@
     falcon::hal::LoadMethod,
     gpu::Chipset,
     num::{
+        self,
         FromSafeCast,
         IntoSafeCast, //
     },
@@ -36,6 +37,9 @@
 mod hal;
 pub(crate) mod sec2;
 
+/// Alignment (in bytes) of falcon memory blocks.
+pub(crate) const MEM_BLOCK_ALIGNMENT: usize = 256;
+
 // TODO[FPRI]: Replace with `ToPrimitive`.
 macro_rules! impl_from_enum_to_u8 {
     ($enum_type:ty) => {
@@ -423,7 +427,7 @@ fn dma_wr(
         target_mem: FalconMem,
         load_offsets: FalconLoadTarget,
     ) -> Result {
-        const DMA_LEN: u32 = 256;
+        const DMA_LEN: u32 = num::usize_into_u32::<{ MEM_BLOCK_ALIGNMENT }>();
 
         // For IMEM, we want to use the start offset as a virtual address tag for each page, since
         // code addresses in the firmware (and the boot vector) are virtual.

-- 
2.53.0