[Stratos-dev] Re: [PATCH V3 6/6] libxl: Allocate MMIO params for GPIO device and update DT

On 04.08.22 10:01, 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-virti...

Signed-off-by: Viresh Kumar viresh.kumar@linaro.org

tools/libs/light/libxl_arm.c | 47 ++++++++++++++++++++++++++++++++++++ 1 file changed, 47 insertions(+)

diff --git a/tools/libs/light/libxl_arm.c b/tools/libs/light/libxl_arm.c index 08a1499c9523..14b95087f027 100644 --- a/tools/libs/light/libxl_arm.c +++ b/tools/libs/light/libxl_arm.c @@ -121,6 +121,15 @@ 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.
  

@@ -974,6 +983,38 @@ 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)
  

+{

• int res;
• res = make_virtio_mmio_node_common(gc, fdt, base, irq);
• 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) {

@@ -1305,6 +1346,12 @@ static int libxl__prepare_dtb(libxl__gc *gc, libxl_domain_config *d_config, FDT( make_virtio_mmio_node_i2c(gc, fdt, i2c->base, i2c->irq) ); }

•    for (i = 0; i < d_config->num_gpios; i++) {
  

•        libxl_device_gpio *gpio = &d_config->gpios[i];
  

•        FDT( make_virtio_mmio_node_gpio(gc, fdt, gpio->base, gpio->irq) );
  

•    }
  

•     if (pfdt)
          FDT( copy_partial_fdt(gc, fdt, pfdt) );
  

I think that patch needs to be updated taking into the account suggestions provided for two previous patches (of course, if you agree with them).

If so, the make_virtio_mmio_node_gpio() should gain "uint32_t backend_domid" argument, etc. And we need to make sure that make_xen_iommu_node() will be called for virtio gpio.

Something like the diff on top of current patch below (not tested):

diff --git a/tools/libs/light/libxl_arm.c b/tools/libs/light/libxl_arm.c index 9bd8d49f3c..54756b3dd5 100644 --- a/tools/libs/light/libxl_arm.c +++ b/tools/libs/light/libxl_arm.c @@ -986,11 +986,11 @@ static int make_virtio_mmio_node_i2c(libxl__gc *gc, void *fdt, uint64_t base,  }

static int make_virtio_mmio_node_gpio(libxl__gc *gc, void *fdt, uint64_t base, -                                      uint32_t irq) +                                      uint32_t irq, uint32_t backend_domid)  {      int res;

-    res = make_virtio_mmio_node_common(gc, fdt, base, irq); +    res = make_virtio_mmio_node_common(gc, fdt, base, irq, backend_domid);      if (res) return res;

res = fdt_begin_node(fdt, "gpio"); @@ -1350,8 +1350,11 @@ next_resize:

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) ); +            FDT( make_virtio_mmio_node_gpio(gc, fdt, gpio->base, gpio->irq, + gpio->backend_domid) );          }

/*

Other changes look good.