Re: [Update][PATCH v9.1 15/15] irqchip: mbigen: Add ACPI support

From: Al Stone
Date: Tue Mar 28 2017 - 15:14:15 EST

On 03/28/2017 06:21 AM, Hanjun Guo wrote:
> With the preparation of platform msi support and interrupt producer
> in commit d44fa3d46079 ("ACPI: Add support for ResourceSource/IRQ
> domain mapping"), we can add mbigen ACPI support now.
>
> Now that the major framework changes are ready, we just need to add
> the ACPI probe code which creates the irqdomain for devices connecting
> to it.
>
> In order to create the irqdomain, we need to know the number of hw
> irqs as input which is provided by mbigen. In DT case, we are using
> "num-pins" property to describe it, and we will take advantage of
> that too using _DSD in ACPI as there is no standard way of describe
> it in ACPI way, also according to the _DSD rule described in
> Documentation/acpi/DSD-properties-rules.txt, it doesn't break
> the rules.
>
> The DSDT is represented as below:
>
> For mbigen,
> Device(MBI0) {
> Name(_HID, "HISI0152")
> Name(_UID, Zero)
> Name(_CRS, ResourceTemplate() {
> Memory32Fixed(ReadWrite, 0xa0080000, 0x10000)
> })
>
> Name(_DSD, Package () {
> ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"),
> Package () {
> Package () {"num-pins", 378}
> }
> })
> }
>
> For devices,
> Device(SAS0) {
> Name(_HID, "HISIxxxx")
> Name(_UID, Zero)
> Name(_CRS, ResourceTemplate() {
> Memory32Fixed(ReadWrite, 0xb0030000, 0x10000)
> Interrupt(ResourceConsumer,..., "\_SB.MBI0") {12, ...}
> })
> }
>
> So for the devices connected to the mbigen, as we clearly say that
> it refers to a specific interrupt controller (mbigen), we can get
> the virq from mbigen's irqdomain once it's created successfully.
>
> Signed-off-by: Hanjun Guo <hanjun.guo@xxxxxxxxxx>
> Signed-off-by: MaJun <majun258@xxxxxxxxxx>
> Cc: Al Stone <ahs3@xxxxxxxxxx>
> Cc: Darren Hart <dvhart@xxxxxxxxxxxxx>
> Cc: Lorenzo Pieralisi <lorenzo.pieralisi@xxxxxxx>
> Cc: Marc Zyngier <marc.zyngier@xxxxxxx>
> ---
> drivers/irqchip/irq-mbigen.c | 75 ++++++++++++++++++++++++++++++++++++++++++--
> 1 file changed, 72 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/irqchip/irq-mbigen.c b/drivers/irqchip/irq-mbigen.c
> index 3756408..061cdb8 100644
> --- a/drivers/irqchip/irq-mbigen.c
> +++ b/drivers/irqchip/irq-mbigen.c
> @@ -16,6 +16,7 @@
> * along with this program. If not, see <http://www.gnu.org/licenses/>.
> */
>
> +#include <linux/acpi.h>
> #include <linux/interrupt.h>
> #include <linux/irqchip.h>
> #include <linux/module.h>
> @@ -180,7 +181,7 @@ static int mbigen_domain_translate(struct irq_domain *d,
> unsigned long *hwirq,
> unsigned int *type)
> {
> - if (is_of_node(fwspec->fwnode)) {
> + if (is_of_node(fwspec->fwnode) || is_acpi_device_node(fwspec->fwnode)) {
> if (fwspec->param_count != 2)
> return -EINVAL;
>
> @@ -271,6 +272,58 @@ static int mbigen_of_create_domain(struct platform_device *pdev,
> return 0;
> }
>
> +#ifdef CONFIG_ACPI
> +static int mbigen_acpi_create_domain(struct platform_device *pdev,
> + struct mbigen_device *mgn_chip)
> +{
> + struct irq_domain *domain;
> + u32 num_pins = 0;
> + int ret;
> +
> + /*
> + * "num-pins" is the total number of interrupt pins implemented in
> + * this mbigen instance, and mbigen is an interrupt controller
> + * connected to ITS converting wired interrupts into MSI, so we
> + * use "num-pins" to alloc MSI vectors which are needed by client
> + * devices connected to it.
> + *
> + * Here is the DSDT device node used for mbigen in firmware:
> + * Device(MBI0) {
> + * Name(_HID, "HISI0152")
> + * Name(_UID, Zero)
> + * Name(_CRS, ResourceTemplate() {
> + * Memory32Fixed(ReadWrite, 0xa0080000, 0x10000)
> + * })
> + *
> + * Name(_DSD, Package () {
> + * ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"),
> + * Package () {
> + * Package () {"num-pins", 378}
> + * }
> + * })
> + * }
> + */

Excellent. These comments I really like. Thanks for doing this!

> + ret = device_property_read_u32(&pdev->dev, "num-pins", &num_pins);
> + if (ret || num_pins == 0)
> + return -EINVAL;
> +
> + domain = platform_msi_create_device_domain(&pdev->dev, num_pins,
> + mbigen_write_msg,
> + &mbigen_domain_ops,
> + mgn_chip);
> + if (!domain)
> + return -ENOMEM;
> +
> + return 0;
> +}
> +#else
> +static inline int mbigen_acpi_create_domain(struct platform_device *pdev,
> + struct mbigen_device *mgn_chip)
> +{
> + return -ENODEV;
> +}
> +#endif
> +
> static int mbigen_device_probe(struct platform_device *pdev)
> {
> struct mbigen_device *mgn_chip;
> @@ -289,9 +342,18 @@ static int mbigen_device_probe(struct platform_device *pdev)
> if (IS_ERR(mgn_chip->base))
> return PTR_ERR(mgn_chip->base);
>
> - err = mbigen_of_create_domain(pdev, mgn_chip);
> - if (err)
> + if (IS_ENABLED(CONFIG_OF) && pdev->dev.of_node)
> + err = mbigen_of_create_domain(pdev, mgn_chip);
> + else if (ACPI_COMPANION(&pdev->dev))
> + err = mbigen_acpi_create_domain(pdev, mgn_chip);
> + else
> + err = -EINVAL;
> +
> + if (err) {
> + dev_err(&pdev->dev, "Failed to create mbi-gen@%p irqdomain",
> + mgn_chip->base);
> return err;
> + }
>
> platform_set_drvdata(pdev, mgn_chip);
> return 0;
> @@ -303,10 +365,17 @@ static int mbigen_device_probe(struct platform_device *pdev)
> };
> MODULE_DEVICE_TABLE(of, mbigen_of_match);
>
> +static const struct acpi_device_id mbigen_acpi_match[] = {
> + { "HISI0152", 0 },
> + {}
> +};
> +MODULE_DEVICE_TABLE(acpi, mbigen_acpi_match);
> +
> static struct platform_driver mbigen_platform_driver = {
> .driver = {
> .name = "Hisilicon MBIGEN-V2",
> .of_match_table = mbigen_of_match,
> + .acpi_match_table = ACPI_PTR(mbigen_acpi_match),
> },
> .probe = mbigen_device_probe,
> };
>

All LGTM.

Reviewed-by: Al Stone <ahs3@xxxxxxxxxx>

--
ciao,
al
-----------------------------------
Al Stone
Software Engineer
Red Hat, Inc.
ahs3@xxxxxxxxxx
-----------------------------------