[PATCH v2 5/7] gpu: nova-core: build SetRegistry entries dynamically

[Zhi Wang]

Convert SetRegistry to store registry entries in a KVec instead of a
fixed-size array. This keeps the existing registry contents unchanged
while making the command ready for entries that are appended based on
runtime state.

No functional change is intended.

Signed-off-by: Zhi Wang <zhiw@xxxxxxxxxx>
---
 drivers/gpu/nova-core/gsp/boot.rs     |  2 +-
 drivers/gpu/nova-core/gsp/commands.rs | 73 +++++++++++++++------------
 2 files changed, 41 insertions(+), 34 deletions(-)

diff --git a/drivers/gpu/nova-core/gsp/boot.rs b/drivers/gpu/nova-core/gsp/boot.rs
index 0a33cf4dd975..55ea8e38aa79 100644
--- a/drivers/gpu/nova-core/gsp/boot.rs
+++ b/drivers/gpu/nova-core/gsp/boot.rs
@@ -94,7 +94,7 @@ pub(crate) fn boot(
             self.cmdq
                 .send_command_no_wait(bar, commands::SetSystemInfo::new(pdev, chipset))?;
             self.cmdq
-                .send_command_no_wait(bar, commands::SetRegistry::new())?;
+                .send_command_no_wait(bar, commands::SetRegistry::new()?)?;
 
             hal.post_boot(&self, &mut ctx, &gsp_fw)?;
 
diff --git a/drivers/gpu/nova-core/gsp/commands.rs b/drivers/gpu/nova-core/gsp/commands.rs
index f84de9f4f045..3dccb012a37e 100644
--- a/drivers/gpu/nova-core/gsp/commands.rs
+++ b/drivers/gpu/nova-core/gsp/commands.rs
@@ -66,37 +66,44 @@ struct RegistryEntry {
 
 /// The `SetRegistry` command.
 pub(crate) struct SetRegistry {
-    entries: [RegistryEntry; Self::NUM_ENTRIES],
+    entries: KVec<RegistryEntry>,
 }
 
 impl SetRegistry {
-    // For now we hard-code the registry entries. Future work will allow others to
-    // be added as module parameters.
-    const NUM_ENTRIES: usize = 3;
-
     /// Creates a new `SetRegistry` command, using a set of hardcoded entries.
-    pub(crate) fn new() -> Self {
-        Self {
-            entries: [
-                // RMSecBusResetEnable - enables PCI secondary bus reset
-                RegistryEntry {
-                    key: "RMSecBusResetEnable",
-                    value: 1,
-                },
-                // RMForcePcieConfigSave - forces GSP-RM to preserve PCI configuration registers on
-                // any PCI reset.
-                RegistryEntry {
-                    key: "RMForcePcieConfigSave",
-                    value: 1,
-                },
-                // RMDevidCheckIgnore - allows GSP-RM to boot even if the PCI dev ID is not found
-                // in the internal product name database.
-                RegistryEntry {
-                    key: "RMDevidCheckIgnore",
-                    value: 1,
-                },
-            ],
-        }
+    pub(crate) fn new() -> Result<Self> {
+        let mut entries = KVec::new();
+
+        // RMSecBusResetEnable - enables PCI secondary bus reset.
+        entries.push(
+            RegistryEntry {
+                key: "RMSecBusResetEnable",
+                value: 1,
+            },
+            GFP_KERNEL,
+        )?;
+
+        // RMForcePcieConfigSave - forces GSP-RM to preserve PCI configuration registers on any PCI
+        // reset.
+        entries.push(
+            RegistryEntry {
+                key: "RMForcePcieConfigSave",
+                value: 1,
+            },
+            GFP_KERNEL,
+        )?;
+
+        // RMDevidCheckIgnore - allows GSP-RM to boot even if the PCI dev ID is not found in the
+        // internal product name database.
+        entries.push(
+            RegistryEntry {
+                key: "RMDevidCheckIgnore",
+                value: 1,
+            },
+            GFP_KERNEL,
+        )?;
+
+        Ok(Self { entries })
     }
 }
 
@@ -107,15 +114,15 @@ impl CommandToGsp for SetRegistry {
     type InitError = Infallible;
 
     fn init(&self) -> impl Init<Self::Command, Self::InitError> {
-        Self::Command::init(Self::NUM_ENTRIES as u32, self.variable_payload_len() as u32)
+        Self::Command::init(self.entries.len() as u32, self.variable_payload_len() as u32)
     }
 
     fn variable_payload_len(&self) -> usize {
         let mut key_size = 0;
-        for i in 0..Self::NUM_ENTRIES {
-            key_size += self.entries[i].key.len() + 1; // +1 for NULL terminator
+        for entry in self.entries.iter() {
+            key_size += entry.key.len() + 1; // +1 for NULL terminator
         }
-        Self::NUM_ENTRIES * size_of::<fw::commands::PackedRegistryEntry>() + key_size
+        self.entries.len() * size_of::<fw::commands::PackedRegistryEntry>() + key_size
     }
 
     fn init_variable_payload(
@@ -123,12 +130,12 @@ fn init_variable_payload(
         dst: &mut SBufferIter<core::array::IntoIter<&mut [u8], 2>>,
     ) -> Result {
         let string_data_start_offset = size_of::<Self::Command>()
-            + Self::NUM_ENTRIES * size_of::<fw::commands::PackedRegistryEntry>();
+            + self.entries.len() * size_of::<fw::commands::PackedRegistryEntry>();
 
         // Array for string data.
         let mut string_data = KVec::new();
 
-        for entry in self.entries.iter().take(Self::NUM_ENTRIES) {
+        for entry in self.entries.iter() {
             dst.write_all(
                 fw::commands::PackedRegistryEntry::new(
                     (string_data_start_offset + string_data.len()) as u32,
-- 
2.51.0