Re: [PATCH v3 11/25] bus: mhi: ep: Add support for managing MMIO registers

[Hemant Kumar <hemantk@codeaurora.org>]

Hi Mani

On 2/12/2022 10:21 AM, Manivannan Sadhasivam wrote:
> Add support for managing the Memory Mapped Input Output (MMIO) registers
> of the MHI bus. All MHI operations are carried out using the MMIO registers
> by both host and the endpoint device.
> 
> The MMIO registers reside inside the endpoint device memory (fixed
> location based on the platform) and the address is passed by the MHI EP
> controller driver during its registration.
> 
> Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
> ---
>   drivers/bus/mhi/ep/Makefile   |   2 +-
>   drivers/bus/mhi/ep/internal.h |  37 +++++
>   drivers/bus/mhi/ep/main.c     |   6 +-
>   drivers/bus/mhi/ep/mmio.c     | 274 ++++++++++++++++++++++++++++++++++
>   include/linux/mhi_ep.h        |  18 +++
>   5 files changed, 335 insertions(+), 2 deletions(-)
>   create mode 100644 drivers/bus/mhi/ep/mmio.c
> 
> diff --git a/drivers/bus/mhi/ep/Makefile b/drivers/bus/mhi/ep/Makefile
> index 64e29252b608..a1555ae287ad 100644
> --- a/drivers/bus/mhi/ep/Makefile
> +++ b/drivers/bus/mhi/ep/Makefile
> @@ -1,2 +1,2 @@
>   obj-$(CONFIG_MHI_BUS_EP) += mhi_ep.o
> -mhi_ep-y := main.o
> +mhi_ep-y := main.o mmio.o
> diff --git a/drivers/bus/mhi/ep/internal.h b/drivers/bus/mhi/ep/internal.h
> index e313a2546664..2c756a90774c 100644
> --- a/drivers/bus/mhi/ep/internal.h
> +++ b/drivers/bus/mhi/ep/internal.h
> @@ -101,6 +101,17 @@ struct mhi_generic_ctx {
>   	__u64 wp __packed __aligned(4);
>   };
>   
> +/**
> + * enum mhi_ep_execenv - MHI Endpoint Execution Environment
> + * @MHI_EP_SBL_EE: Secondary Bootloader
> + * @MHI_EP_AMSS_EE: Advanced Mode Subscriber Software
> + */
> +enum mhi_ep_execenv {
> +	MHI_EP_SBL_EE = 1,
> +	MHI_EP_AMSS_EE = 2,
> +	MHI_EP_UNRESERVED
> +};
can we move or use the exec env definitions from common header ?
> +
>   enum mhi_ep_ring_type {
>   	RING_TYPE_CMD = 0,
>   	RING_TYPE_ER,
> @@ -157,4 +168,30 @@ struct mhi_ep_chan {
>   	bool skip_td;
>   };
>   
> +/* MMIO related functions */
> +u32 mhi_ep_mmio_read(struct mhi_ep_cntrl *mhi_cntrl, u32 offset);
> +void mhi_ep_mmio_write(struct mhi_ep_cntrl *mhi_cntrl, u32 offset, u32 val);
> +void mhi_ep_mmio_masked_write(struct mhi_ep_cntrl *mhi_cntrl, u32 offset, u32 mask, u32 val);
> +u32 mhi_ep_mmio_masked_read(struct mhi_ep_cntrl *dev, u32 offset, u32 mask);
> +void mhi_ep_mmio_enable_ctrl_interrupt(struct mhi_ep_cntrl *mhi_cntrl);
> +void mhi_ep_mmio_disable_ctrl_interrupt(struct mhi_ep_cntrl *mhi_cntrl);
> +void mhi_ep_mmio_enable_cmdb_interrupt(struct mhi_ep_cntrl *mhi_cntrl);
> +void mhi_ep_mmio_disable_cmdb_interrupt(struct mhi_ep_cntrl *mhi_cntrl);
> +void mhi_ep_mmio_enable_chdb_a7(struct mhi_ep_cntrl *mhi_cntrl, u32 chdb_id);
can we get rid of a7 from function and macros ?
> +void mhi_ep_mmio_disable_chdb_a7(struct mhi_ep_cntrl *mhi_cntrl, u32 chdb_id);
[..]
-- 
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