This patch allocates Virtio MMIO params (IRQ and memory region) and pass
them to the backend, also update Guest device-tree based on Virtio GPIO
DT bindings [1].

[1] https://www.kernel.org/doc/Documentation/devicetree/bindings/gpio/gpio-virtio.yaml

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
---
 tools/libs/light/libxl_arm.c | 51 ++++++++++++++++++++++++++++++++++++
 1 file changed, 51 insertions(+)

diff --git a/tools/libs/light/libxl_arm.c b/tools/libs/light/libxl_arm.c
index 93ea8e3d3fa3..c0ffb7f179d4 100644
--- a/tools/libs/light/libxl_arm.c
+++ b/tools/libs/light/libxl_arm.c
@@ -119,6 +119,15 @@ int libxl__arch_domain_prepare_config(libxl__gc *gc,
             return rc;
     }
 
+    for (i = 0; i < d_config->num_gpios; i++) {
+        libxl_device_gpio *gpio = &d_config->gpios[i];
+
+    int rc = alloc_virtio_mmio_params(gc, &gpio->base, &gpio->irq,
+            &virtio_mmio_base, &virtio_mmio_irq);
+    if (rc)
+        return rc;
+    }
+
     /*
      * Every virtio-mmio device uses one emulated SPI. If Virtio devices are
      * present, make sure that we allocate enough SPIs for them.
@@ -976,6 +985,38 @@ static int make_virtio_mmio_node_i2c(libxl__gc *gc, void *fdt, uint64_t base,
     return fdt_end_node(fdt);
 }
 
+static int make_virtio_mmio_node_gpio(libxl__gc *gc, void *fdt, uint64_t base,
+                                      uint32_t irq, uint32_t backend_domid)
+{
+    int res;
+
+    res = make_virtio_mmio_node_common(gc, fdt, base, irq, backend_domid);
+    if (res) return res;
+
+    res = fdt_begin_node(fdt, "gpio");
+    if (res) return res;
+
+    res = fdt_property_compat(gc, fdt, 1, "virtio,device29");
+    if (res) return res;
+
+    res = fdt_property(fdt, "gpio-controller", NULL, 0);
+    if (res) return res;
+
+    res = fdt_property_cell(fdt, "#gpio-cells", 2);
+    if (res) return res;
+
+    res = fdt_property(fdt, "interrupt-controller", NULL, 0);
+    if (res) return res;
+
+    res = fdt_property_cell(fdt, "#interrupt-cells", 2);
+    if (res) return res;
+
+    res = fdt_end_node(fdt);
+    if (res) return res;
+
+    return fdt_end_node(fdt);
+}
+
 static const struct arch_info *get_arch_info(libxl__gc *gc,
                                              const struct xc_dom_image *dom)
 {
@@ -1308,6 +1349,16 @@ static int libxl__prepare_dtb(libxl__gc *gc, libxl_domain_config *d_config,
                                            i2c->backend_domid) );
         }
 
+        for (i = 0; i < d_config->num_gpios; i++) {
+            libxl_device_gpio *gpio = &d_config->gpios[i];
+
+            if (gpio->backend_domid != LIBXL_TOOLSTACK_DOMID)
+                iommu_needed = true;
+
+            FDT( make_virtio_mmio_node_gpio(gc, fdt, gpio->base, gpio->irq,
+                                            gpio->backend_domid) );
+        }
+
         /*
          * Note, this should be only called after creating all virtio-mmio
          * device nodes
-- 
2.31.1.272.g89b43f80a514

On 09.08.22 08:34, Viresh Kumar wrote:

Hello Viresh

> This patch allocates Virtio MMIO params (IRQ and memory region) and pass
> them to the backend, also update Guest device-tree based on Virtio GPIO
> DT bindings [1].
>
> [1] https://www.kernel.org/doc/Documentation/devicetree/bindings/gpio/gpio-virtio.yaml
>
> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
> ---
>   tools/libs/light/libxl_arm.c | 51 ++++++++++++++++++++++++++++++++++++
>   1 file changed, 51 insertions(+)
>
> diff --git a/tools/libs/light/libxl_arm.c b/tools/libs/light/libxl_arm.c
> index 93ea8e3d3fa3..c0ffb7f179d4 100644
> --- a/tools/libs/light/libxl_arm.c
> +++ b/tools/libs/light/libxl_arm.c
> @@ -119,6 +119,15 @@ int libxl__arch_domain_prepare_config(libxl__gc *gc,
>               return rc;
>       }
>   
> +    for (i = 0; i < d_config->num_gpios; i++) {
> +        libxl_device_gpio *gpio = &d_config->gpios[i];
> +

Nit: This blank line is not needed, I think


> +    int rc = alloc_virtio_mmio_params(gc, &gpio->base, &gpio->irq,
> +            &virtio_mmio_base, &virtio_mmio_irq);

Nit: Something wrong with the indentation and looks like the blank line 
is needed here.


> +    if (rc)
> +        return rc;
> +    }
> +
>       /*
>        * Every virtio-mmio device uses one emulated SPI. If Virtio devices are
>        * present, make sure that we allocate enough SPIs for them.
> @@ -976,6 +985,38 @@ static int make_virtio_mmio_node_i2c(libxl__gc *gc, void *fdt, uint64_t base,
>       return fdt_end_node(fdt);
>   }
>   
> +static int make_virtio_mmio_node_gpio(libxl__gc *gc, void *fdt, uint64_t base,
> +                                      uint32_t irq, uint32_t backend_domid)
> +{
> +    int res;
> +
> +    res = make_virtio_mmio_node_common(gc, fdt, base, irq, backend_domid);
> +    if (res) return res;
> +
> +    res = fdt_begin_node(fdt, "gpio");
> +    if (res) return res;
> +
> +    res = fdt_property_compat(gc, fdt, 1, "virtio,device29");
> +    if (res) return res;
> +
> +    res = fdt_property(fdt, "gpio-controller", NULL, 0);
> +    if (res) return res;
> +
> +    res = fdt_property_cell(fdt, "#gpio-cells", 2);
> +    if (res) return res;
> +
> +    res = fdt_property(fdt, "interrupt-controller", NULL, 0);
> +    if (res) return res;
> +
> +    res = fdt_property_cell(fdt, "#interrupt-cells", 2);
> +    if (res) return res;
> +
> +    res = fdt_end_node(fdt);
> +    if (res) return res;
> +
> +    return fdt_end_node(fdt);
> +}
> +
>   static const struct arch_info *get_arch_info(libxl__gc *gc,
>                                                const struct xc_dom_image *dom)
>   {
> @@ -1308,6 +1349,16 @@ static int libxl__prepare_dtb(libxl__gc *gc, libxl_domain_config *d_config,
>                                              i2c->backend_domid) );
>           }
>   
> +        for (i = 0; i < d_config->num_gpios; i++) {
> +            libxl_device_gpio *gpio = &d_config->gpios[i];
> +
> +            if (gpio->backend_domid != LIBXL_TOOLSTACK_DOMID)
> +                iommu_needed = true;
> +
> +            FDT( make_virtio_mmio_node_gpio(gc, fdt, gpio->base, gpio->irq,
> +                                            gpio->backend_domid) );
> +        }
> +
>           /*
>            * Note, this should be only called after creating all virtio-mmio
>            * device nodes


Preferably with above fixed:

Reviewed-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>


-- 
Regards,

Oleksandr Tyshchenko