Re: [PATCH 6/7] cxl/mem: Create a helper to setup device regs

Jonathan Cameron
2021-04-08T17:35:16Z

On Wed, 7 Apr 2021 15:26:24 -0700
Ben Widawsky <ben.widawsky@intel.com> wrote:

> Memory devices have a list of required register regions within the
> register block, but this isn't required of all CXL components or
> devices. To make things more tidy, and allow for easily setting up other
> block types in this loop, the helper is introduced.

Two things in here, the move and allowing it to be missing.
I would call that out explicitly in the patch description.

>
> Signed-off-by: Ben Widawsky <ben.widawsky@intel.com>
> ---
> drivers/cxl/mem.c | 38 +++++++++++++++++++++++---------------
> 1 file changed, 23 insertions(+), 15 deletions(-)
>
> diff --git a/drivers/cxl/mem.c b/drivers/cxl/mem.c
> index 49f651694cb0..b7342aaf38c4 100644
> --- a/drivers/cxl/mem.c
> +++ b/drivers/cxl/mem.c
> @@ -974,6 +974,24 @@ static int cxl_mem_dvsec(struct pci_dev *pdev, int dvsec)
> return 0;
> }
>
> +static int __cxl_setup_device_regs(struct cxl_mem *cxlm, void __iomem *base)

Naming is a little unusual. Normally __ would imply unlocked or something
like that, whereas here it's mostly implying more error checks.

I don't immediately have a good idea for a name however...

> +{
> + struct cxl_regs *regs = &cxlm->regs;
> + struct pci_dev *pdev = cxlm->pdev;
> + struct device *dev = &pdev->dev;
> +
> + cxl_setup_device_regs(dev, base, &regs->device_regs);
> + if (!regs->status || !regs->mbox || !regs->memdev) {
> + dev_err(dev, "registers not found: %s%s%s\n",
> + !regs->status ? "status " : "",
> + !regs->mbox ? "mbox " : "",
> + !regs->memdev ? "memdev" : "");
> + return -ENXIO;
> + }
> +
> + return 0;
> +}
> +
> /**
> * cxl_mem_setup_regs() - Setup necessary MMIO.
> * @cxlm: The CXL memory device to communicate with.
> @@ -986,12 +1004,11 @@ static int cxl_mem_dvsec(struct pci_dev *pdev, int dvsec)
> */
> static int cxl_mem_setup_regs(struct cxl_mem *cxlm)
> {
> - struct cxl_regs *regs = &cxlm->regs;
> struct pci_dev *pdev = cxlm->pdev;
> struct device *dev = &pdev->dev;
> u32 regloc_size, regblocks;
> void __iomem *base;
> - int regloc, i;
> + int regloc, i, rc;
>
> regloc = cxl_mem_dvsec(pdev, PCI_DVSEC_ID_CXL_REGLOC_OFFSET);
> if (!regloc) {
> @@ -1021,23 +1038,14 @@ static int cxl_mem_setup_regs(struct cxl_mem *cxlm)
> if (IS_ERR(base))
> return PTR_ERR(base);
>
> - cxl_setup_device_regs(dev, base, &regs->device_regs);
> - if (!regs->status || !regs->mbox || !regs->memdev) {
> - dev_err(dev, "registers not found: %s%s%s\n",
> - !regs->status ? "status " : "",
> - !regs->mbox ? "mbox " : "",
> - !regs->memdev ? "memdev" : "");
> - return -ENXIO;
> - }
> + rc = __cxl_setup_device_regs(cxlm, base);
> + if (rc)
> + return rc;
> +
> break;
> }
> }
>
> - if (i == regblocks) {
> - dev_err(dev, "Missing register locator for device registers\n");
> - return -ENXIO;
> - }
> -
> return 0;
> }
>