enhance GIC v3 ITS and enable it on i.MX 95 EVK A55 platform #92346
Conversation
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Contributor
JiafeiPan
commented
Jun 28, 2025
JiafeiPan
commented
- Enabled DMA noncoherent for GIC v3 and GIC v3 ITS
- Fixed some bugs for GIC v3 ITS
- Enabled GIC ITS on i.MX 95 EVK A55 platform
- Added i.MX 95 EVK support for test arm64_gicv3_its
github-actions
bot
added
area: Interrupt Controller
platform: ARM
github-actions
bot
requested review from
carlocaione,
dbaluta,
dcpleung,
dleach02,
ithinuel,
iuliana-prodan,
nashif,
npitre,
povergoing,
SgrrZhf,
wearyzen,
yangbolu1991 and
ycsin
GIC redistributor on Some platform are connected to a non-coherent downstream interconnect, it need to use Non-cahable and Non-shareable access atttributes to access external memory. And also flush the data cache after CPU update related memory. Signed-off-by: Jiafei Pan <[email protected]>
| @@ -73,4 +73,13 @@ config GIC_SAFE_CONFIG | |||
| crash the OS has already been started. With this enabled, it will bypass | |||
| GIC distributor configuration if it has been configured by other OS. | |||
|
|
|||
| config GIC_V3_RDIST_DMA_NONCOHERENT | |||
There was a problem hiding this comment.
Suggest to use a new properity 'dma-noncoherent' in GIC and ITS DT node to indicate this hardware feature respectively instead of a CONFIG entry, just like GICv3/ITS driver in Linux.
There was a problem hiding this comment.
Prefer to use kconfig to make the code to be static includable but not checking properties at runtime in order to reduce the resource usage. thanks.
There was a problem hiding this comment.
Per your suggestion, added a new kconfig GIC_V3_ITS_DMA_NONCOHERENT for ITS driver, so that GIC redistribute and ITS could configure dma coherent separately, thanks.
JiafeiPan
force-pushed
the
develop/imx95-netc-gic
branch
from
eb1aab7 to
6d877ca
Compare
Add DMA noncoherent support on GICv3 ITS driver. Signed-off-by: Jiafei Pan <[email protected]>
For RDbase used by its command, When GITS_TYPER.PTA = 1, physicall address is used, the RDbase field consist of bits[51:16] of the address, so need to left shift the address by 16 bits. But when GITS_TYPER.PTA = 0, PE number is used, no need to shit anymore. Signed-off-by: Jiafei Pan <[email protected]>
GIC v3 ITS is initialized in pre-kernel stage in which sleep function can't work yet, so use busy delay in pre-kernel stage and use sleep delay in post-kernel stage. Signed-off-by: Jiafei Pan <[email protected]>
Enlarge the memory size to 10M bytes as it is not enough if run some networking application. Signed-off-by: Jiafei Pan <[email protected]>
Added dts node for GIC v3 ITS. Signed-off-by: Jiafei Pan <[email protected]>
In case of ITS is enabled, need to include LPI in the total number of irq. Signed-off-by: Jiafei Pan <[email protected]>
GIC redistribute and ITS on i.MX 95 is DMA noncoherent, so enable CONFIG_GIC_V3_RDIST_DMA_NONCOHERENT and CONFIG_GIC_V3_GIC_DMA_NONCOHERENT. Signed-off-by: Jiafei Pan <[email protected]>
GIC ITS depends on kernel heap, so move GIC initialize to be behind of heap which initialization priority is CONFIG_KERNEL_INIT_PRIORITY_OBJECTS (it is 30 by default). MU mailbox and SCMI objects depend on GIC, so set their init priority to be same with GIC, the initialization sequence decided by the dts dependency although they use the same init priority. Signed-off-by: Jiafei Pan <[email protected]>
Add imx95_evk support, as hardware limication, it only has 832 LPIs. Signed-off-by: Jiafei Pan <[email protected]>
|
dleach02
approved these changes
Jul 29, 2025
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.