On Tue, Nov 21, 2023 at 05:38:28PM +0530, Manivannan Sadhasivam wrote: > On Tue, Nov 21, 2023 at 01:55:22PM +0300, Serge Semin wrote: > > Hi Mani > > > > On Tue, Nov 21, 2023 at 11:56:29AM +0530, Manivannan Sadhasivam wrote: > > > On Fri, Nov 17, 2023 at 11:03:48AM +0100, Kory Maincent wrote: > > > > This patch series fix the support of dw-edma HDMA NATIVE IP. > > > > I can only test it in remote HDMA IP setup with single dma transfer, but > > > > with these fixes it works properly. > > > > > > > > Few fixes has also been added for eDMA version. Similarly to HDMA I have > > > > tested only eDMA in remote setup. > > > > > > > > > > Just out of curiosity, can you share how you are setting EDMA_MF_HDMA_NATIVE? > > > > This topic has already been concerned on v1 (in another context > > though): > > https://lore.kernel.org/dmaengine/20230621151948.36125997@kmaincent-XPS-13-7390/ > > > > Here is the repo with the out-of-tree driver Kory said he was using > > together with the kernel's version of the DW eDMA/hDMA driver: > > https://github.com/Brainchip-Inc/akida_dw_edma > > > > Thanks Sergey, I missed it! But looks like we are not focusing on the HDMA > integration in designware-ep.c. Have you/anyone thought about it? Was it > discussed previously that I missed? No. We haven't discussed that in the framework of this patchset. > > HDMA is used in one of the recent Qcom SoCs (SA8775) that Qcom folks are > bringing up and I'd like to have a common solution like we have for eDMA. AFAICS it won't be that easy to do for HDMA. Unlike eDMA, HDMA doesn't have a handy global config registers to determine the number of R/W channels. Kory also said that auto-detecting them by dummy-writing to all the CH_EN registers didn't work either because all, even unavailable, channels CSRs were writable. This part was discussed earlier: https://lore.kernel.org/lkml/20230607144014.6356a197@kmaincent-XPS-13-7390/ So if you don't come up with some more clever solution, then alas the number of R/W channels will need to be specified by the platform code/driver. Regarding how to auto-detect HDMA. I can't be absolutely sure whether it will work but if we assume that: 1. HDMA reg-space is always unrolled (mapped over a separate reg-space), 2. Lowest 16 bits of base+0x8 are RO in EDMA (DMA_CTRL_OFF) and RW in HDMA (prefetch CSR), then we can implement a procedure like this: 1. If iATU/xDMA reg-space is specified and it's writable at the xDMA-base+0x8 then it's HDMA controller and amount of channels is supposed to be pre-initialized by the low-level platform driver, otherwise it's eDMA and the read value can be used to determine the number of channels. 2. If iATU/xDMA reg-space isn't specified then the viewport-based eDMA auto-detection procedure will be executed. For all of that you'll need to fix the dw_pcie_edma_find_chip()/dw_pcie_edma_detect() method somehow. Alternatively, to keep things simple you can convert the dw_pcie_edma_find_chip()/dw_pcie_edma_detect() methods to just relying on the HDMA settings being fully specified by the low-level drivers. -Serge(y) > > - Mani > > > -Serge(y) > > > > > > > > - Mani > > > > > > > Changes in v2: > > > > - Update comments and fix typos. > > > > - Removed patches that tackle hypothetical bug and then were not pertinent. > > > > - Add the similar HDMA race condition in remote setup fix to eDMA IP driver. > > > > > > > > Changes in v3: > > > > - Fix comment style. > > > > - Split a patch in two to differ bug fix and simple harmless typo. > > > > > > > > Changes in v4: > > > > - Update patch git commit message. > > > > - Link to v3: https://lore.kernel.org/r/20231011-b4-feature_hdma_mainline-v3-0-24ee0c979c6f@xxxxxxxxxxx > > > > > > > > Changes in v5: > > > > - No change > > > > - Rebase to mainline 6.7-rc1 > > > > - Link to v4: https://lore.kernel.org/r/20231011-b4-feature_hdma_mainline-v4-0-43d417b93138@xxxxxxxxxxx > > > > > > > > Changes in v6: > > > > - Fix several commit messages and comments. > > > > - Link to v5: https://lore.kernel.org/r/20231114-b4-feature_hdma_mainline-v5-0-7bc86d83c6f7@xxxxxxxxxxx > > > > > > > > Signed-off-by: Kory Maincent <kory.maincent@xxxxxxxxxxx> > > > > --- > > > > Kory Maincent (6): > > > > dmaengine: dw-edma: Fix the ch_count hdma callback > > > > dmaengine: dw-edma: Fix wrong interrupt bit set for HDMA > > > > dmaengine: dw-edma: HDMA_V0_REMOTEL_STOP_INT_EN typo fix > > > > dmaengine: dw-edma: Add HDMA remote interrupt configuration > > > > dmaengine: dw-edma: HDMA: Add sync read before starting the DMA transfer in remote setup > > > > dmaengine: dw-edma: eDMA: Add sync read before starting the DMA transfer in remote setup > > > > > > > > drivers/dma/dw-edma/dw-edma-v0-core.c | 17 +++++++++++++++ > > > > drivers/dma/dw-edma/dw-hdma-v0-core.c | 39 +++++++++++++++++++++++------------ > > > > drivers/dma/dw-edma/dw-hdma-v0-regs.h | 2 +- > > > > 3 files changed, 44 insertions(+), 14 deletions(-) > > > > --- > > > > base-commit: b85ea95d086471afb4ad062012a4d73cd328fa86 > > > > change-id: 20231011-b4-feature_hdma_mainline-b6c57f8e3b5d > > > > > > > > Best regards, > > > > -- > > > > Köry Maincent, Bootlin > > > > Embedded Linux and kernel engineering > > > > https://bootlin.com > > > > > > > > > > -- > > > மணிவண்ணன் சதாசிவம் > > -- > மணிவண்ணன் சதாசிவம்
