On Fri, Mar 12, 2021 at 09:36:00PM +0800, Bin Meng wrote: > QEMU ppce500 target can dynamically instantiate an eTSEC device on > a platform bus if "-device eTSEC" is given to QEMU. It is presented > as a "simple-bus" in the device tree, with an additional compatible > string "qemu,platform". > > Let's create a virtual memory mapping for it in misc_init_r(), in > preparation to adding eTSEC support. > > Signed-off-by: Bin Meng <bmeng...@gmail.com> > > --- > > Changes in v2: > - turn on CONFIG_SIMPLE_BUS_CORRECT_RANGE in qemu-ppce500_defconfig > > board/emulation/qemu-ppce500/Kconfig | 6 ++++++ > board/emulation/qemu-ppce500/qemu-ppce500.c | 18 ++++++++++++++++++ > configs/qemu-ppce500_defconfig | 1 + > 3 files changed, 25 insertions(+) > > diff --git a/board/emulation/qemu-ppce500/Kconfig > b/board/emulation/qemu-ppce500/Kconfig > index 4312d986d8..1c5aa18aa9 100644 > --- a/board/emulation/qemu-ppce500/Kconfig > +++ b/board/emulation/qemu-ppce500/Kconfig > @@ -9,4 +9,10 @@ config SYS_VENDOR > config SYS_CONFIG_NAME > default "qemu-ppce500" > > +config PLATFORM_BUS_MAP_ADDR > + hex > + default 0xf0000000 > + help > + The QEMU platform bus base mapped address in the virtual memory space. > + > endif > diff --git a/board/emulation/qemu-ppce500/qemu-ppce500.c > b/board/emulation/qemu-ppce500/qemu-ppce500.c > index daa103c564..0960dd1f97 100644 > --- a/board/emulation/qemu-ppce500/qemu-ppce500.c > +++ b/board/emulation/qemu-ppce500/qemu-ppce500.c > @@ -14,6 +14,8 @@ > #include <net.h> > #include <pci.h> > #include <time.h> > +#include <dm/simple_bus.h> > +#include <dm/uclass-internal.h> > #include <asm/global_data.h> > #include <asm/processor.h> > #include <asm/mmu.h> > @@ -148,6 +150,22 @@ int misc_init_r(void) > */ > disable_tlb(find_tlb_idx((void *)CONFIG_SYS_TMPVIRT, 1)); > > + /* > + * Detect the presence of the platform bus node, and > + * create a virtual memory mapping for it. > + */ > + for (ret = uclass_find_first_device(UCLASS_SIMPLE_BUS, &dev); > + dev; > + ret = uclass_find_next_device(&dev)) { > + if (device_is_compatible(dev, "qemu,platform")) { > + struct simple_bus_plat *plat = dev_get_uclass_plat(dev); > + > + assert(!tlb_map_range(CONFIG_PLATFORM_BUS_MAP_ADDR, > + plat->target, plat->size, > + TLB_MAP_IO));
A break here, maybe? If there are multiple qemu,platform nodes, your code will attempt to create multiple TLB mappings towards the same virtual address CONFIG_PLATFORM_BUS_MAP_ADDR, which will not work. So better avoid that. And maybe you can refactor this into a dedicated function, similar to what exists for PCI. > + } > + } > + > return 0; > } } > > diff --git a/configs/qemu-ppce500_defconfig b/configs/qemu-ppce500_defconfig > index 536fe7d6e1..151834b4cf 100644 > --- a/configs/qemu-ppce500_defconfig > +++ b/configs/qemu-ppce500_defconfig > @@ -28,6 +28,7 @@ CONFIG_OF_BOARD=y > CONFIG_ENV_OVERWRITE=y > CONFIG_SYS_RELOC_GD_ENV_ADDR=y > CONFIG_DM=y > +CONFIG_SIMPLE_BUS_CORRECT_RANGE=y > CONFIG_BLK=y > CONFIG_HAVE_BLOCK_DEVICE=y > CONFIG_MPC8XXX_GPIO=y > -- > 2.25.1 >