[PATCH v7 2/4] gpu: nova-core: prepare Spec and Revision types for boot0/boot42

[John Hubbard <jhubbard@nvidia.com>]

1) Decouple Revision from boot0.

2) Enhance Revision, which in turn simplifies Spec::new().

3) Also, slightly enhance the comment about Spec, to be more precise.

Cc: Alexandre Courbot <acourbot@nvidia.com>
Cc: Danilo Krummrich <dakr@kernel.org>
Cc: Timur Tabi <ttabi@nvidia.com>
Signed-off-by: John Hubbard <jhubbard@nvidia.com>
---
 drivers/gpu/nova-core/gpu.rs  | 25 ++++++++++++-------------
 drivers/gpu/nova-core/regs.rs | 11 ++++++++++-
 2 files changed, 22 insertions(+), 14 deletions(-)

diff --git a/drivers/gpu/nova-core/gpu.rs b/drivers/gpu/nova-core/gpu.rs
index 7fd9e91771a6..acf564fee9c8 100644
--- a/drivers/gpu/nova-core/gpu.rs
+++ b/drivers/gpu/nova-core/gpu.rs
@@ -143,17 +143,8 @@ fn try_from(value: u8) -> Result<Self> {
 }
 
 pub(crate) struct Revision {
-    major: u8,
-    minor: u8,
-}
-
-impl Revision {
-    fn from_boot0(boot0: regs::NV_PMC_BOOT_0) -> Self {
-        Self {
-            major: boot0.major_revision(),
-            minor: boot0.minor_revision(),
-        }
-    }
+    pub(crate) major: u8,
+    pub(crate) minor: u8,
 }
 
 impl fmt::Display for Revision {
@@ -162,7 +153,7 @@ fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
     }
 }
 
-/// Structure holding the metadata of the GPU.
+/// Structure holding a basic description of the GPU: Architecture, Chipset and Revision.
 pub(crate) struct Spec {
     chipset: Chipset,
     /// The revision of the chipset.
@@ -173,9 +164,17 @@ impl Spec {
     fn new(bar: &Bar0) -> Result<Spec> {
         let boot0 = regs::NV_PMC_BOOT_0::read(bar);
 
+        Spec::try_from(boot0)
+    }
+}
+
+impl TryFrom<regs::NV_PMC_BOOT_0> for Spec {
+    type Error = Error;
+
+    fn try_from(boot0: regs::NV_PMC_BOOT_0) -> Result<Self> {
         Ok(Self {
             chipset: boot0.chipset()?,
-            revision: Revision::from_boot0(boot0),
+            revision: boot0.revision(),
         })
     }
 }
diff --git a/drivers/gpu/nova-core/regs.rs b/drivers/gpu/nova-core/regs.rs
index 934003cab8a8..8c9af3c59708 100644
--- a/drivers/gpu/nova-core/regs.rs
+++ b/drivers/gpu/nova-core/regs.rs
@@ -24,7 +24,8 @@
     },
     gpu::{
         Architecture,
-        Chipset, //
+        Chipset,
+        Revision, //
     },
     num::FromSafeCast,
 };
@@ -56,6 +57,14 @@ pub(crate) fn chipset(self) -> Result<Chipset> {
             })
             .and_then(Chipset::try_from)
     }
+
+    /// Returns the revision information of the chip.
+    pub(crate) fn revision(self) -> Revision {
+        Revision {
+            major: self.major_revision(),
+            minor: self.minor_revision(),
+        }
+    }
 }
 
 // PBUS
-- 
2.51.2