Re: [PATCH v2 07/27] ocxl: Add functions to map/unmap LPC memory

[Frederic Barrat]

Le 03/12/2019 Ã 04:46, Alastair D'Silva a ÃcritÂ:
> From: Alastair D'Silva <alastair@xxxxxxxxxxx>
>
> Add functions to map/unmap LPC memory
>
> Signed-off-by: Alastair D'Silva <alastair@xxxxxxxxxxx>
> ---
>   drivers/misc/ocxl/config.c        |  4 +++
>   drivers/misc/ocxl/core.c          | 50 +++++++++++++++++++++++++++++++
>   drivers/misc/ocxl/ocxl_internal.h |  3 ++
>   include/misc/ocxl.h               | 18 +++++++++++
>   4 files changed, 75 insertions(+)
>
> diff --git a/drivers/misc/ocxl/config.c b/drivers/misc/ocxl/config.c
> index c8e19bfb5ef9..fb0c3b6f8312 100644
> --- a/drivers/misc/ocxl/config.c
> +++ b/drivers/misc/ocxl/config.c
> @@ -568,6 +568,10 @@ static int read_afu_lpc_memory_info(struct pci_dev *dev,
>   		afu->special_purpose_mem_size =
>   			total_mem_size - lpc_mem_size;
>   	}
> +
> +	dev_info(&dev->dev, "Probed LPC memory of %#llx bytes and special purpose memory of %#llx bytes\n",
> +		afu->lpc_mem_size, afu->special_purpose_mem_size);
> +
>   	return 0;
>   }
>   
> diff --git a/drivers/misc/ocxl/core.c b/drivers/misc/ocxl/core.c
> index 2531c6cf19a0..98611faea219 100644
> --- a/drivers/misc/ocxl/core.c
> +++ b/drivers/misc/ocxl/core.c
> @@ -210,6 +210,55 @@ static void unmap_mmio_areas(struct ocxl_afu *afu)
>   	release_fn_bar(afu->fn, afu->config.global_mmio_bar);
>   }
>   
> +int ocxl_afu_map_lpc_mem(struct ocxl_afu *afu)
> +{
> +	struct pci_dev *dev = to_pci_dev(afu->fn->dev.parent);
> +
> +	if ((afu->config.lpc_mem_size + afu->config.special_purpose_mem_size) == 0)
> +		return 0;
> +
> +	afu->lpc_base_addr = ocxl_link_lpc_map(afu->fn->link, dev);
> +	if (afu->lpc_base_addr == 0)
> +		return -EINVAL;
> +
> +	if (afu->config.lpc_mem_size) {
> +		afu->lpc_res.start = afu->lpc_base_addr + afu->config.lpc_mem_offset;
> +		afu->lpc_res.end = afu->lpc_res.start + afu->config.lpc_mem_size - 1;
> +	}
> +
> +	if (afu->config.special_purpose_mem_size) {
> +		afu->special_purpose_res.start = afu->lpc_base_addr +
> +						 afu->config.special_purpose_mem_offset;
> +		afu->special_purpose_res.end = afu->special_purpose_res.start +
> +					       afu->config.special_purpose_mem_size - 1;
> +	}
> +
> +	return 0;
> +}
> +EXPORT_SYMBOL_GPL(ocxl_afu_map_lpc_mem);
> +
> +struct resource *ocxl_afu_lpc_mem(struct ocxl_afu *afu)
> +{
> +	return &afu->lpc_res;
> +}
> +EXPORT_SYMBOL_GPL(ocxl_afu_lpc_mem);
> +
> +static void unmap_lpc_mem(struct ocxl_afu *afu)
> +{
> +	struct pci_dev *dev = to_pci_dev(afu->fn->dev.parent);
> +
> +	if (afu->lpc_res.start || afu->special_purpose_res.start) {
> +		void *link = afu->fn->link;
> +
> +		ocxl_link_lpc_release(link, dev);
> +
> +		afu->lpc_res.start = 0;
> +		afu->lpc_res.end = 0;
> +		afu->special_purpose_res.start = 0;
> +		afu->special_purpose_res.end = 0;
> +	}
> +}
> +
>   static int configure_afu(struct ocxl_afu *afu, u8 afu_idx, struct pci_dev *dev)
>   {
>   	int rc;
> @@ -251,6 +300,7 @@ static int configure_afu(struct ocxl_afu *afu, u8 afu_idx, struct pci_dev *dev)
>   
>   static void deconfigure_afu(struct ocxl_afu *afu)
>   {
> +	unmap_lpc_mem(afu);
>   	unmap_mmio_areas(afu);
>   	reclaim_afu_pasid(afu);
>   	reclaim_afu_actag(afu);
> diff --git a/drivers/misc/ocxl/ocxl_internal.h b/drivers/misc/ocxl/ocxl_internal.h
> index 20b417e00949..9f4b47900e62 100644
> --- a/drivers/misc/ocxl/ocxl_internal.h
> +++ b/drivers/misc/ocxl/ocxl_internal.h
> @@ -52,6 +52,9 @@ struct ocxl_afu {
>   	void __iomem *global_mmio_ptr;
>   	u64 pp_mmio_start;
>   	void *private;
> +	u64 lpc_base_addr; /* Covers both LPC & special purpose memory */
> +	struct resource lpc_res;
> +	struct resource special_purpose_res;
>   };
>   
>   enum ocxl_context_status {
> diff --git a/include/misc/ocxl.h b/include/misc/ocxl.h
> index 06dd5839e438..6f7c02f0d5e3 100644
> --- a/include/misc/ocxl.h
> +++ b/include/misc/ocxl.h
> @@ -212,6 +212,24 @@ int ocxl_irq_set_handler(struct ocxl_context *ctx, int irq_id,
>   
>   // AFU Metadata
>   
> +/**
> + * Map the LPC system & special purpose memory for an AFU
> + *
> + * Do not call this during device discovery, as there may me multiple
> + * devices on a link, and the memory is mapped for the whole link, not
> + * just one device. It should only be called after all devices have
> + * registered their memory on the link.
> + *
> + * afu: The AFU that has the LPC memory to map
> + */
> +extern int ocxl_afu_map_lpc_mem(struct ocxl_afu *afu);
> +
> +/**
> + * Get the physical address range of LPC memory for an AFU
> + * afu: The AFU associated with the LPC memory
> + */
> +extern struct resource *ocxl_afu_lpc_mem(struct ocxl_afu *afu);
> +


You can drop the useless 'extern'.

  Fred


>   /**
>    * Get a pointer to the config for an AFU
>    *