John Hubbard
2025-Nov-19 06:30 UTC
[PATCH 02/11] gpu: nova-core: add ImemNs section infrastructure
On 11/18/25 5:54 PM, Alexandre Courbot wrote:> On Sat Nov 15, 2025 at 8:30 AM JST, Timur Tabi wrote: >> The GSP booter firmware in Turing and GA100 includes a third memory >> section called ImemNs, which is non-secure IMEM. This section must >> be loaded separately from DMEM and secure IMEM, but only if it >> actually exists. >> >> Signed-off-by: Timur Tabi <ttabi at nvidia.com> >> --- >> drivers/gpu/nova-core/falcon.rs | 18 ++++++++++++++++-- >> drivers/gpu/nova-core/firmware/booter.rs | 9 +++++++++ >> drivers/gpu/nova-core/firmware/fwsec.rs | 5 +++++ >> 3 files changed, 30 insertions(+), 2 deletions(-) >> >> diff --git a/drivers/gpu/nova-core/falcon.rs b/drivers/gpu/nova-core/falcon.rs >> index 0e0935dbb927..ece8b92a627e 100644 >> --- a/drivers/gpu/nova-core/falcon.rs >> +++ b/drivers/gpu/nova-core/falcon.rs >> @@ -239,6 +239,8 @@ fn from(value: PeregrineCoreSelect) -> Self { >> pub(crate) enum FalconMem { >> /// Secure Instruction Memory. >> ImemSec, >> + /// Non-Secure Instruction Memory. >> + ImemNs, > > So, seeing how this is taking shape I now think we should just have one > Imem variant: > > Imem { secure: bool },ohhh, boolean args are usually not a good idea, because they make the callsite non-self-documenting. That's also true even in magical languages such as Rust. :) Let's prefer enum args over bools, generally, please. So for example (there are other ways to structure things, and this is just the enum aspect of it): enum ImemSecurity { Secure, NonSecure, } Imem { security: ImemSecurity },> > This makes matching easier for the common case of "we want to do > something in case of Imem, regardless of the secure flag". Something > like > > FalconMem::ImemSec | FalconMem::ImemNs => { > > becomes: > > FalconMem::Imem { .. } => { > > And if you need to use the flag, you can change e.g.: > > FalconMem::ImemSec | FalconMem::ImemNs => { > regs::NV_PFALCON_FALCON_IMEMC::default() > .set_secure(target_mem == FalconMem::ImemSec) > > into > > FalconMem::Imem { secure } => {See, this is hard and misleading to read. It reads like "secure Imem", until you think at it a bit. Devastating! :)> regs::NV_PFALCON_FALCON_IMEMC::default() > .set_secure(secure) > > Which is simpler and easier to read. > > This also removes the need to rename `Imem` into `ImemSec`, so the first > two patches can be merged into one. >thanks, -- John Hubbard
Alexandre Courbot
2025-Nov-19 06:55 UTC
[PATCH 02/11] gpu: nova-core: add ImemNs section infrastructure
On Wed Nov 19, 2025 at 3:30 PM JST, John Hubbard wrote:> On 11/18/25 5:54 PM, Alexandre Courbot wrote: >> On Sat Nov 15, 2025 at 8:30 AM JST, Timur Tabi wrote: >>> The GSP booter firmware in Turing and GA100 includes a third memory >>> section called ImemNs, which is non-secure IMEM. This section must >>> be loaded separately from DMEM and secure IMEM, but only if it >>> actually exists. >>> >>> Signed-off-by: Timur Tabi <ttabi at nvidia.com> >>> --- >>> drivers/gpu/nova-core/falcon.rs | 18 ++++++++++++++++-- >>> drivers/gpu/nova-core/firmware/booter.rs | 9 +++++++++ >>> drivers/gpu/nova-core/firmware/fwsec.rs | 5 +++++ >>> 3 files changed, 30 insertions(+), 2 deletions(-) >>> >>> diff --git a/drivers/gpu/nova-core/falcon.rs b/drivers/gpu/nova-core/falcon.rs >>> index 0e0935dbb927..ece8b92a627e 100644 >>> --- a/drivers/gpu/nova-core/falcon.rs >>> +++ b/drivers/gpu/nova-core/falcon.rs >>> @@ -239,6 +239,8 @@ fn from(value: PeregrineCoreSelect) -> Self { >>> pub(crate) enum FalconMem { >>> /// Secure Instruction Memory. >>> ImemSec, >>> + /// Non-Secure Instruction Memory. >>> + ImemNs, >> >> So, seeing how this is taking shape I now think we should just have one >> Imem variant: >> >> Imem { secure: bool }, > > ohhh, boolean args are usually not a good idea, because they make the > callsite non-self-documenting. > > That's also true even in magical languages such as Rust. :)I fully agree; that's why I made the field named so its name needs to be specified every time. :) Maybe `is_secure` would have been better though.> > Let's prefer enum args over bools, generally, please. So for example > (there are other ways to structure things, and this is just the > enum aspect of it): > > enum ImemSecurity { > Secure, > NonSecure, > } > > Imem { security: ImemSecurity },That would change FalconMem::Imem { secure: true } into FalconMem::Imem {security: ImemSecurity::Secure } If we want to use an enum I think we can remove the name: Imem(ImemSecurity), So we can specify `Imem` as FalconMem::Imem(ImemSecurity::Secure) which is as explicit, and a bit shorter.> >> >> This makes matching easier for the common case of "we want to do >> something in case of Imem, regardless of the secure flag". Something >> like >> >> FalconMem::ImemSec | FalconMem::ImemNs => { >> >> becomes: >> >> FalconMem::Imem { .. } => { >> >> And if you need to use the flag, you can change e.g.: >> >> FalconMem::ImemSec | FalconMem::ImemNs => { >> regs::NV_PFALCON_FALCON_IMEMC::default() >> .set_secure(target_mem == FalconMem::ImemSec) >> >> into >> >> FalconMem::Imem { secure } => { > > See, this is hard and misleading to read. It reads like "secure > Imem", until you think at it a bit. Devastating! :)Renaming into `is_secure` would alleviate that, but the `ImemSecurity` enum is arguably as good, so I'm fine with it as well. And an enum can also be used as a type to method arguments, which carries more semantics than `is_secure: bool`. So agreed, this is better.