| Message ID | CAHuqX+H1ELmquVL5uKhFdQr3gveYvNJPmVUrgWMzzSbnXt6N1Q@mail.gmail.com |
|---|---|
| State | New |
| Headers | show |
On 5 October 2013 13:41, Giridhar Maruthy <giridhar.maruthy@linaro.org> wrote: > I am using mach-virt in qemu which boots correctly when RAM start > address is 0x8000000. But if I change the address to anything like > 0x9000000, the mach-virt machine just hangs, not even an error > message. The kernel automatically figures out where in physical memory it should decompress itself to (CONFIG_AUTO_ZRELADDR), but the mechanism it uses to do this assumes that RAM starts at a 128MB boundary. So we must keep the board's RAM start address at a 128MB boundary. Why did you want to move VIRT_MEM up? There's plenty of space below it still, I would have thought. -- PMM
On 5 October 2013 10:19, Peter Maydell <peter.maydell@linaro.org> wrote: > On 5 October 2013 13:41, Giridhar Maruthy <giridhar.maruthy@linaro.org> wrote: >> I am using mach-virt in qemu which boots correctly when RAM start >> address is 0x8000000. But if I change the address to anything like >> 0x9000000, the mach-virt machine just hangs, not even an error >> message. > > The kernel automatically figures out where in physical memory it should > decompress itself to (CONFIG_AUTO_ZRELADDR), but the mechanism > it uses to do this assumes that RAM starts at a 128MB boundary. ok. But changing the RAM start to 0x20000000 (2 followed by seven zeros) still does not work even though is at 128MB boundary. > So we must keep the board's RAM start address at a 128MB boundary. > Why did you want to move VIRT_MEM up? There's plenty of space > below it still, I would have thought. The purpose is that I wanted to use mach-virt as a base to test other machines' properties like different RAM base and size, peripherals at different locations, etc. Thanks, Giridhar
On 5 October 2013 14:20, Giridhar Maruthy <giridhar.maruthy@linaro.org> wrote: > On 5 October 2013 10:19, Peter Maydell <peter.maydell@linaro.org> wrote: >> On 5 October 2013 13:41, Giridhar Maruthy <giridhar.maruthy@linaro.org> wrote: >>> I am using mach-virt in qemu which boots correctly when RAM start >>> address is 0x8000000. But if I change the address to anything like >>> 0x9000000, the mach-virt machine just hangs, not even an error >>> message. >> >> The kernel automatically figures out where in physical memory it should >> decompress itself to (CONFIG_AUTO_ZRELADDR), but the mechanism >> it uses to do this assumes that RAM starts at a 128MB boundary. > > ok. But changing the RAM start to 0x20000000 (2 followed by seven > zeros) still does not work even though is at 128MB boundary. Well, in theory that should work. You'll need to debug why the kernel isn't booting, then (try using a gdb connected to qemu's gdb stub); I'm afraid that's a pretty painful process. -- PMM
diff --git a/hw/arm/virt.c b/hw/arm/virt.c index 448a0e5..d3797c8 100644 --- a/hw/arm/virt.c +++ b/hw/arm/virt.c @@ -101,7 +101,7 @@ static const MemMapEntry a15memmap[] = { [VIRT_UART] = { 0x1008000, 0x1000 }, [VIRT_MMIO] = { 0x2000000, 0x200 }, /* ...repeating for a total of NUM_VIRTIO_TRANSPORTS, each of that size */ - [VIRT_MEM] = { 0x8000000, 30ULL * 1024 * 1024 * 1024 }, + [VIRT_MEM] = { 0x9000000, 30ULL * 1024 * 1024 * 1024 }, };