| Message ID | 1479346221-18474-1-git-send-email-linux@roeck-us.net (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 17 November 2016 at 01:30, Guenter Roeck <linux@roeck-us.net> wrote: > While customary, the /chosen and /memory devicetree nodes do not have to > exist. Create if necessary. Also create the /memory/device_type property > if needed. > > Signed-off-by: Guenter Roeck <linux@roeck-us.net> > --- > The problem is seen with the latest version of the Linux kernel in > linux-next (next-20161116), where many of the /chosen and /memory nodes > in arm devicetree files have been removed. This results in a kernel hang > (sabrelite) or qemu abort (imx25-pdk). The lack of a memory node sounds to me like a bug in the Linux device trees. The 0.1 specification at http://www.devicetree.org/specifications/ says on page 21 "the following nodes shall be present at the root of all devicetrees: [...] At least one memory node". There's no harm in QEMU being robust against bogus input, though, especially if the dtbs are common in the wild, so this patch is worth having. (And 'chosen' is definitely optional.) I've applied this patch to target-arm.next. thanks -- PMM
diff --git a/hw/arm/boot.c b/hw/arm/boot.c index 942416d..ff621e4 100644 --- a/hw/arm/boot.c +++ b/hw/arm/boot.c @@ -9,6 +9,7 @@ #include "qemu/osdep.h" #include "qapi/error.h" +#include <libfdt.h> #include "hw/hw.h" #include "hw/arm/arm.h" #include "hw/arm/linux-boot-if.h" @@ -486,6 +487,17 @@ static int load_dtb(hwaddr addr, const struct arm_boot_info *binfo, g_free(nodename); } } else { + Error *err = NULL; + + rc = fdt_path_offset(fdt, "/memory"); + if (rc < 0) { + qemu_fdt_add_subnode(fdt, "/memory"); + } + + if (!qemu_fdt_getprop(fdt, "/memory", "device_type", NULL, &err)) { + qemu_fdt_setprop_string(fdt, "/memory", "device_type", "memory"); + } + rc = qemu_fdt_setprop_sized_cells(fdt, "/memory", "reg", acells, binfo->loader_start, scells, binfo->ram_size); @@ -495,6 +507,11 @@ static int load_dtb(hwaddr addr, const struct arm_boot_info *binfo, } } + rc = fdt_path_offset(fdt, "/chosen"); + if (rc < 0) { + qemu_fdt_add_subnode(fdt, "/chosen"); + } + if (binfo->kernel_cmdline && *binfo->kernel_cmdline) { rc = qemu_fdt_setprop_string(fdt, "/chosen", "bootargs", binfo->kernel_cmdline);
While customary, the /chosen and /memory devicetree nodes do not have to exist. Create if necessary. Also create the /memory/device_type property if needed. Signed-off-by: Guenter Roeck <linux@roeck-us.net> --- The problem is seen with the latest version of the Linux kernel in linux-next (next-20161116), where many of the /chosen and /memory nodes in arm devicetree files have been removed. This results in a kernel hang (sabrelite) or qemu abort (imx25-pdk). hw/arm/boot.c | 17 +++++++++++++++++ 1 file changed, 17 insertions(+)