On Tue, 25 Jan 2022 19:09:25 -0800
Dan Williams <dan.j.williams@xxxxxxxxx> wrote:
> Unlike the decoder enumeration for "root decoders" described by platform
> firmware, standard coders can be enumerated from the component registers
> space once the base address has been identified (via PCI, ACPI, or
> another mechanism).
>
> Add common infrastructure for HDM (Host-managed-Device-Memory) Decoder
> enumeration and share it between host-bridge, upstream switch port, and
> cxl_test defined decoders.
>
> The locking model for switch level decoders is to hold the port lock
> over the enumeration. This facilitates moving the dport and decoder
> enumeration to a 'port' driver. For now, the only enumerator of decoder
> resources is the cxl_acpi root driver.
>
> [ben: fixup kdoc]
> Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx>
One trivial thing noticed.
> ---
> Changes since v3:
> - Fixup kdoc for devm_cxl_enumerate_decoders() (Ben)
> - Cleanup a sparse warning around __iomem usage (Ben)
...
> +/**
> + * devm_cxl_setup_hdm - map HDM decoder component registers
> + * @port: cxl_port to map
I think you drop it again later in the series, but it would be nice to
avoid kernel doc warnings whilst the host parameter is here.
> + */
> +struct cxl_hdm *devm_cxl_setup_hdm(struct device *host, struct cxl_port *port)
> +{
> + struct device *dev = &port->dev;
> + void __iomem *crb, *hdm;
> + struct cxl_hdm *cxlhdm;
> +
> + cxlhdm = devm_kzalloc(host, sizeof(*cxlhdm), GFP_KERNEL);
> + if (!cxlhdm)
> + return ERR_PTR(-ENOMEM);
> +
> + cxlhdm->port = port;
> + crb = devm_cxl_iomap_block(host, port->component_reg_phys,
> + CXL_COMPONENT_REG_BLOCK_SIZE);
> + if (!crb) {
> + dev_err(dev, "No component registers mapped\n");
> + return ERR_PTR(-ENXIO);
> + }
> +
> + hdm = map_hdm_decoder_regs(port, crb);
> + if (IS_ERR(hdm))
> + return ERR_CAST(hdm);
> + cxlhdm->regs.hdm_decoder = hdm;
> +
> + parse_hdm_decoder_caps(cxlhdm);
> + if (cxlhdm->decoder_count == 0) {
> + dev_err(dev, "Spec violation. Caps invalid\n");
> + return ERR_PTR(-ENXIO);
> + }
> +
> + return cxlhdm;
> +}
> +EXPORT_SYMBOL_NS_GPL(devm_cxl_setup_hdm, CXL);
>
