Re: [PATCH v5 10/16] cxl/pci: Update RAS handler interfaces to also support CXL PCIe Ports

[Jonathan Cameron <Jonathan.Cameron@huawei.com>]

On Tue, 7 Jan 2025 08:38:46 -0600
Terry Bowman <terry.bowman@amd.com> wrote:

> CXL PCIe Port Protocol Error handling support will be added to the
> CXL drivers in the future. In preparation, rename the existing
> interfaces to support handling all CXL PCIe Port Protocol Errors.
> 
> The driver's RAS support functions currently rely on a 'struct
> cxl_dev_state' type parameter, which is not available for CXL Port
> devices. However, since the same CXL RAS capability structure is
> needed across most CXL components and devices, a common handling
> approach should be adopted.
> 
> To accommodate this, update the __cxl_handle_cor_ras() and
> __cxl_handle_ras() functions to use a `struct device` instead of
> `struct cxl_dev_state`.
> 
> No functional changes are introduced.
> 
> [1] CXL 3.1 Spec, 8.2.4 CXL.cache and CXL.mem Registers
> 
> Signed-off-by: Terry Bowman <terry.bowman@amd.com>
> Reviewed-by: Alejandro Lucero <alucerop@amd.com>
A few protections you introduce in later patches should be here
to make the change to dev safer.

Otherwise looks fine.

Jonathan

> ---
>  drivers/cxl/core/pci.c | 17 ++++++++---------
>  1 file changed, 8 insertions(+), 9 deletions(-)
> 
> diff --git a/drivers/cxl/core/pci.c b/drivers/cxl/core/pci.c
> index 97e6a15bea88..5699ee5b29df 100644
> --- a/drivers/cxl/core/pci.c
> +++ b/drivers/cxl/core/pci.c
> @@ -650,7 +650,7 @@ void read_cdat_data(struct cxl_port *port)
>  }
>  EXPORT_SYMBOL_NS_GPL(read_cdat_data, "CXL");
>  
> -static void __cxl_handle_cor_ras(struct cxl_dev_state *cxlds,
> +static void __cxl_handle_cor_ras(struct device *dev,
>  				 void __iomem *ras_base)
>  {
>  	void __iomem *addr;
> @@ -663,13 +663,13 @@ static void __cxl_handle_cor_ras(struct cxl_dev_state *cxlds,
>  	status = readl(addr);
>  	if (status & CXL_RAS_CORRECTABLE_STATUS_MASK) {
>  		writel(status & CXL_RAS_CORRECTABLE_STATUS_MASK, addr);
> -		trace_cxl_aer_correctable_error(cxlds->cxlmd, status);
> +		trace_cxl_aer_correctable_error(to_cxl_memdev(dev), status);

I'd expect the protection on the dev being a memdev to be in this patch
given the relaxation on the interface.  Pull that bit forward form patch 14.


>  	}
>  }
>  
>  static void cxl_handle_endpoint_cor_ras(struct cxl_dev_state *cxlds)
>  {
> -	return __cxl_handle_cor_ras(cxlds, cxlds->regs.ras);
> +	return __cxl_handle_cor_ras(&cxlds->cxlmd->dev, cxlds->regs.ras);
>  }
>  
>  /* CXL spec rev3.0 8.2.4.16.1 */
> @@ -693,8 +693,7 @@ static void header_log_copy(void __iomem *ras_base, u32 *log)
>   * Log the state of the RAS status registers and prepare them to log the
>   * next error status. Return 1 if reset needed.
>   */
> -static bool __cxl_handle_ras(struct cxl_dev_state *cxlds,
> -				  void __iomem *ras_base)
> +static bool __cxl_handle_ras(struct device *dev, void __iomem *ras_base)
>  {
>  	u32 hl[CXL_HEADERLOG_SIZE_U32];
>  	void __iomem *addr;
> @@ -721,7 +720,7 @@ static bool __cxl_handle_ras(struct cxl_dev_state *cxlds,
>  	}
>  
>  	header_log_copy(ras_base, hl);
> -	trace_cxl_aer_uncorrectable_error(cxlds->cxlmd, status, fe, hl);
> +	trace_cxl_aer_uncorrectable_error(to_cxl_memdev(dev), status, fe, hl);
>  	writel(status & CXL_RAS_UNCORRECTABLE_STATUS_MASK, addr);

As above.  If the interface takes a dev we need to check it is the right
type of dev.

>  
>  	return true;
> @@ -729,7 +728,7 @@ static bool __cxl_handle_ras(struct cxl_dev_state *cxlds,
>  
>  static bool cxl_handle_endpoint_ras(struct cxl_dev_state *cxlds)
>  {
> -	return __cxl_handle_ras(cxlds, cxlds->regs.ras);
> +	return __cxl_handle_ras(&cxlds->cxlmd->dev, cxlds->regs.ras);
>  }
>  
>  #ifdef CONFIG_PCIEAER_CXL
> @@ -818,13 +817,13 @@ EXPORT_SYMBOL_NS_GPL(cxl_dport_init_ras_reporting, "CXL");
>  static void cxl_handle_rdport_cor_ras(struct cxl_dev_state *cxlds,
>  					  struct cxl_dport *dport)
>  {
> -	return __cxl_handle_cor_ras(cxlds, dport->regs.ras);
> +	return __cxl_handle_cor_ras(&cxlds->cxlmd->dev, dport->regs.ras);
>  }
>  
>  static bool cxl_handle_rdport_ras(struct cxl_dev_state *cxlds,
>  				       struct cxl_dport *dport)
>  {
> -	return __cxl_handle_ras(cxlds, dport->regs.ras);
> +	return __cxl_handle_ras(&cxlds->cxlmd->dev, dport->regs.ras);
>  }
>  
>  /*