Subject: Re: Fwd: [PATCH v4 06/18] cxl: Isolate a few bare-metal-specific calls

From: Manoj Kumar <[email-masked]>
Date: Sun, 21 Feb 2016 16:13:08 -0600

Reviewed-by: Manoj Kumar <[email-masked]>

---
Manoj Kumar

> Subject: [PATCH v4 06/18] cxl: Isolate a few bare-metal-specific calls
> Date: Tue, 16 Feb 2016 22:38:59 +0100
> From: Frederic Barrat <[email-masked]>
> To: [email-masked], [email-masked],
> [email-masked], [email-masked]
>
> A few functions are mostly common between bare-metal and guest and
> just need minor tuning. To avoid crowding the backend API, introduce a
> few 'if' based on the CPU being in HV mode.
>
> Co-authored-by: Christophe Lombard <[email-masked]>
> Signed-off-by: Frederic Barrat <[email-masked]>
> Signed-off-by: Christophe Lombard <[email-masked]>
> Acked-by: Ian Munsie <[email-masked]>
> ---
>   drivers/misc/cxl/context.c |  3 ++-
>   drivers/misc/cxl/cxl.h     |  7 +++++--
>   drivers/misc/cxl/debugfs.c |  4 ++++
>   drivers/misc/cxl/fault.c   | 19 +++++++++++--------
>   4 files changed, 22 insertions(+), 11 deletions(-)
>
> diff --git a/drivers/misc/cxl/context.c b/drivers/misc/cxl/context.c
> index aa65262..46f9844 100644
> --- a/drivers/misc/cxl/context.c
> +++ b/drivers/misc/cxl/context.c
> @@ -95,7 +95,8 @@ int cxl_context_init(struct cxl_context *ctx, struct
> cxl_afu *afu, bool master,
>           return i;
>
>       ctx->pe = i;
> -    ctx->elem = &ctx->afu->spa[i];
> +    if (cpu_has_feature(CPU_FTR_HVMODE))
> +        ctx->elem = &ctx->afu->spa[i];
>       ctx->pe_inserted = false;
>
>       /*
> diff --git a/drivers/misc/cxl/cxl.h b/drivers/misc/cxl/cxl.h
> index 02065b4..40f6783 100644
> --- a/drivers/misc/cxl/cxl.h
> +++ b/drivers/misc/cxl/cxl.h
> @@ -560,8 +560,11 @@ static inline bool cxl_adapter_link_ok(struct cxl
> *cxl)
>   {
>       struct pci_dev *pdev;
>
> -    pdev = to_pci_dev(cxl->dev.parent);
> -    return !pci_channel_offline(pdev);
> +    if (cpu_has_feature(CPU_FTR_HVMODE)) {
> +        pdev = to_pci_dev(cxl->dev.parent);
> +        return !pci_channel_offline(pdev);
> +    }
> +    return true;
>   }
>
>   static inline void __iomem *_cxl_p1_addr(struct cxl *cxl, cxl_p1_reg_t
> reg)
> diff --git a/drivers/misc/cxl/debugfs.c b/drivers/misc/cxl/debugfs.c
> index 18df6f4..5751899 100644
> --- a/drivers/misc/cxl/debugfs.c
> +++ b/drivers/misc/cxl/debugfs.c
> @@ -118,6 +118,10 @@ void cxl_debugfs_afu_remove(struct cxl_afu *afu)
>   int __init cxl_debugfs_init(void)
>   {
>       struct dentry *ent;
> +
> +    if (!cpu_has_feature(CPU_FTR_HVMODE))
> +        return 0;
> +
>       ent = debugfs_create_dir("cxl", NULL);
>       if (IS_ERR(ent))
>           return PTR_ERR(ent);
> diff --git a/drivers/misc/cxl/fault.c b/drivers/misc/cxl/fault.c
> index ab740a1..9a8650b 100644
> --- a/drivers/misc/cxl/fault.c
> +++ b/drivers/misc/cxl/fault.c
> @@ -254,14 +254,17 @@ void cxl_handle_fault(struct work_struct *fault_work)
>       u64 dar = ctx->dar;
>       struct mm_struct *mm = NULL;
>
> -    if (cxl_p2n_read(ctx->afu, CXL_PSL_DSISR_An) != dsisr ||
> -        cxl_p2n_read(ctx->afu, CXL_PSL_DAR_An) != dar ||
> -        cxl_p2n_read(ctx->afu, CXL_PSL_PEHandle_An) != ctx->pe) {
> -        /* Most likely explanation is harmless - a dedicated process
> -         * has detached and these were cleared by the PSL purge, but
> -         * warn about it just in case */
> -        dev_notice(&ctx->afu->dev, "cxl_handle_fault: Translation fault
> regs changed\n");
> -        return;
> +    if (cpu_has_feature(CPU_FTR_HVMODE)) {
> +        if (cxl_p2n_read(ctx->afu, CXL_PSL_DSISR_An) != dsisr ||
> +            cxl_p2n_read(ctx->afu, CXL_PSL_DAR_An) != dar ||
> +            cxl_p2n_read(ctx->afu, CXL_PSL_PEHandle_An) != ctx->pe) {
> +            /* Most likely explanation is harmless - a dedicated
> +             * process has detached and these were cleared by the
> +             * PSL purge, but warn about it just in case
> +             */
> +            dev_notice(&ctx->afu->dev, "cxl_handle_fault: Translation
> fault regs changed\n");
> +            return;
> +        }
>       }
>
>       /* Early return if the context is being / has been detached */