Re: [PATCH v2 08/10] cxl/pci: Use CDAT DOE mailbox created by PCI core

[Ira Weiny <ira.weiny@intel.com>]

Lukas Wunner wrote:
> The PCI core has just been amended to create a pci_doe_mb struct for
> every DOE instance on device enumeration.
> 
> Drop creation of a (duplicate) CDAT DOE mailbox on cxl probing in favor
> of the one already created by the PCI core.
> 
> Tested-by: Ira Weiny <ira.weiny@intel.com>

Reviewed-by: Ira Weiny <ira.weiny@intel.com>

> Signed-off-by: Lukas Wunner <lukas@wunner.de>
> ---
>  drivers/cxl/core/pci.c | 27 +++++------------------
>  drivers/cxl/cxlmem.h   |  3 ---
>  drivers/cxl/pci.c      | 49 ------------------------------------------
>  3 files changed, 5 insertions(+), 74 deletions(-)
> 
> diff --git a/drivers/cxl/core/pci.c b/drivers/cxl/core/pci.c
> index a02a2b005e6a..5cb6ffa8df0e 100644
> --- a/drivers/cxl/core/pci.c
> +++ b/drivers/cxl/core/pci.c
> @@ -459,27 +459,6 @@ EXPORT_SYMBOL_NS_GPL(cxl_hdm_decode_init, CXL);
>  #define CXL_DOE_TABLE_ACCESS_LAST_ENTRY		0xffff
>  #define CXL_DOE_PROTOCOL_TABLE_ACCESS 2
>  
> -static struct pci_doe_mb *find_cdat_doe(struct device *uport)
> -{
> -	struct cxl_memdev *cxlmd;
> -	struct cxl_dev_state *cxlds;
> -	unsigned long index;
> -	void *entry;
> -
> -	cxlmd = to_cxl_memdev(uport);
> -	cxlds = cxlmd->cxlds;
> -
> -	xa_for_each(&cxlds->doe_mbs, index, entry) {
> -		struct pci_doe_mb *cur = entry;
> -
> -		if (pci_doe_supports_prot(cur, PCI_DVSEC_VENDOR_ID_CXL,
> -					  CXL_DOE_PROTOCOL_TABLE_ACCESS))
> -			return cur;
> -	}
> -
> -	return NULL;
> -}
> -
>  #define CDAT_DOE_REQ(entry_handle)					\
>  	(FIELD_PREP(CXL_DOE_TABLE_ACCESS_REQ_CODE,			\
>  		    CXL_DOE_TABLE_ACCESS_REQ_CODE_READ) |		\
> @@ -569,10 +548,14 @@ void read_cdat_data(struct cxl_port *port)
>  	struct pci_doe_mb *cdat_doe;
>  	struct device *dev = &port->dev;
>  	struct device *uport = port->uport;
> +	struct cxl_memdev *cxlmd = to_cxl_memdev(uport);
> +	struct cxl_dev_state *cxlds = cxlmd->cxlds;
> +	struct pci_dev *pdev = to_pci_dev(cxlds->dev);
>  	size_t cdat_length;
>  	int rc;
>  
> -	cdat_doe = find_cdat_doe(uport);
> +	cdat_doe = pci_find_doe_mailbox(pdev, PCI_DVSEC_VENDOR_ID_CXL,
> +					CXL_DOE_PROTOCOL_TABLE_ACCESS);
>  	if (!cdat_doe) {
>  		dev_dbg(dev, "No CDAT mailbox\n");
>  		return;
> diff --git a/drivers/cxl/cxlmem.h b/drivers/cxl/cxlmem.h
> index ab138004f644..e1a1b23cf56c 100644
> --- a/drivers/cxl/cxlmem.h
> +++ b/drivers/cxl/cxlmem.h
> @@ -227,7 +227,6 @@ struct cxl_endpoint_dvsec_info {
>   * @component_reg_phys: register base of component registers
>   * @info: Cached DVSEC information about the device.
>   * @serial: PCIe Device Serial Number
> - * @doe_mbs: PCI DOE mailbox array
>   * @mbox_send: @dev specific transport for transmitting mailbox commands
>   *
>   * See section 8.2.9.5.2 Capacity Configuration and Label Storage for
> @@ -264,8 +263,6 @@ struct cxl_dev_state {
>  	resource_size_t component_reg_phys;
>  	u64 serial;
>  
> -	struct xarray doe_mbs;
> -
>  	int (*mbox_send)(struct cxl_dev_state *cxlds, struct cxl_mbox_cmd *cmd);
>  };
>  
> diff --git a/drivers/cxl/pci.c b/drivers/cxl/pci.c
> index 33083a522fd1..f8b8e514a3c6 100644
> --- a/drivers/cxl/pci.c
> +++ b/drivers/cxl/pci.c
> @@ -8,7 +8,6 @@
>  #include <linux/mutex.h>
>  #include <linux/list.h>
>  #include <linux/pci.h>
> -#include <linux/pci-doe.h>
>  #include <linux/aer.h>
>  #include <linux/io.h>
>  #include "cxlmem.h"
> @@ -359,52 +358,6 @@ static int cxl_setup_regs(struct pci_dev *pdev, enum cxl_regloc_type type,
>  	return rc;
>  }
>  
> -static void cxl_pci_destroy_doe(void *mbs)
> -{
> -	xa_destroy(mbs);
> -}
> -
> -static void devm_cxl_pci_create_doe(struct cxl_dev_state *cxlds)
> -{
> -	struct device *dev = cxlds->dev;
> -	struct pci_dev *pdev = to_pci_dev(dev);
> -	u16 off = 0;
> -
> -	xa_init(&cxlds->doe_mbs);
> -	if (devm_add_action(&pdev->dev, cxl_pci_destroy_doe, &cxlds->doe_mbs)) {
> -		dev_err(dev, "Failed to create XArray for DOE's\n");
> -		return;
> -	}
> -
> -	/*
> -	 * Mailbox creation is best effort.  Higher layers must determine if
> -	 * the lack of a mailbox for their protocol is a device failure or not.
> -	 */
> -	pci_doe_for_each_off(pdev, off) {
> -		struct pci_doe_mb *doe_mb;
> -
> -		doe_mb = pcim_doe_create_mb(pdev, off);
> -		if (IS_ERR(doe_mb)) {
> -			dev_err(dev, "Failed to create MB object for MB @ %x\n",
> -				off);
> -			continue;
> -		}
> -
> -		if (!pci_request_config_region_exclusive(pdev, off,
> -							 PCI_DOE_CAP_SIZEOF,
> -							 dev_name(dev)))
> -			pci_err(pdev, "Failed to exclude DOE registers\n");
> -
> -		if (xa_insert(&cxlds->doe_mbs, off, doe_mb, GFP_KERNEL)) {
> -			dev_err(dev, "xa_insert failed to insert MB @ %x\n",
> -				off);
> -			continue;
> -		}
> -
> -		dev_dbg(dev, "Created DOE mailbox @%x\n", off);
> -	}
> -}
> -
>  /*
>   * Assume that any RCIEP that emits the CXL memory expander class code
>   * is an RCD
> @@ -469,8 +422,6 @@ static int cxl_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
>  
>  	cxlds->component_reg_phys = map.resource;
>  
> -	devm_cxl_pci_create_doe(cxlds);
> -
>  	rc = cxl_map_component_regs(&pdev->dev, &cxlds->regs.component,
>  				    &map, BIT(CXL_CM_CAP_CAP_ID_RAS));
>  	if (rc)
> -- 
> 2.39.1
>