| Message ID | 20210917075057.20924-9-mark.cave-ayland@ilande.co.uk |
|---|---|
| State | New |
| Headers | show |
| Series | nubus: bus, device, bridge, IRQ and address space improvements | expand |
Le 17/09/2021 à 09:50, Mark Cave-Ayland a écrit : > According to "Designing Cards and Drivers for the Macintosh Family" any attempt > to access an unimplemented address location on Nubus generates a bus error. MacOS > uses a custom bus error handler to detect empty Nubus slots, and with the current > implementation assumes that all slots are occupied as the Nubus transactions > never fail. > > Switch nubus_slot_ops and nubus_super_slot_ops over to use {read,write}_with_attrs > and hard-code them to return MEMTX_DECODE_ERROR so that unoccupied Nubus slots > will generate the expected bus error. > > Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk> > Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org> > --- > hw/nubus/nubus-bus.c | 34 ++++++++++++++++++---------------- > 1 file changed, 18 insertions(+), 16 deletions(-) > > diff --git a/hw/nubus/nubus-bus.c b/hw/nubus/nubus-bus.c > index 39182db065..a617459a4f 100644 > --- a/hw/nubus/nubus-bus.c > +++ b/hw/nubus/nubus-bus.c > @@ -20,23 +20,23 @@ static NubusBus *nubus_find(void) > return NUBUS_BUS(object_resolve_path_type("", TYPE_NUBUS_BUS, NULL)); > } > > -static void nubus_slot_write(void *opaque, hwaddr addr, uint64_t val, > - unsigned int size) > +static MemTxResult nubus_slot_write(void *opaque, hwaddr addr, uint64_t val, > + unsigned size, MemTxAttrs attrs) > { > - /* read only */ > trace_nubus_slot_write(addr, val, size); > + return MEMTX_DECODE_ERROR; > } > > -static uint64_t nubus_slot_read(void *opaque, hwaddr addr, > - unsigned int size) > +static MemTxResult nubus_slot_read(void *opaque, hwaddr addr, uint64_t *data, > + unsigned size, MemTxAttrs attrs) > { > trace_nubus_slot_read(addr, size); > - return 0; > + return MEMTX_DECODE_ERROR; > } > > static const MemoryRegionOps nubus_slot_ops = { > - .read = nubus_slot_read, > - .write = nubus_slot_write, > + .read_with_attrs = nubus_slot_read, > + .write_with_attrs = nubus_slot_write, > .endianness = DEVICE_BIG_ENDIAN, > .valid = { > .min_access_size = 1, > @@ -44,23 +44,25 @@ static const MemoryRegionOps nubus_slot_ops = { > }, > }; > > -static void nubus_super_slot_write(void *opaque, hwaddr addr, uint64_t val, > - unsigned int size) > +static MemTxResult nubus_super_slot_write(void *opaque, hwaddr addr, > + uint64_t val, unsigned size, > + MemTxAttrs attrs) > { > - /* read only */ > trace_nubus_super_slot_write(addr, val, size); > + return MEMTX_DECODE_ERROR; > } > > -static uint64_t nubus_super_slot_read(void *opaque, hwaddr addr, > - unsigned int size) > +static MemTxResult nubus_super_slot_read(void *opaque, hwaddr addr, > + uint64_t *data, unsigned size, > + MemTxAttrs attrs) > { > trace_nubus_super_slot_read(addr, size); > - return 0; > + return MEMTX_DECODE_ERROR; > } > > static const MemoryRegionOps nubus_super_slot_ops = { > - .read = nubus_super_slot_read, > - .write = nubus_super_slot_write, > + .read_with_attrs = nubus_super_slot_read, > + .write_with_attrs = nubus_super_slot_write, > .endianness = DEVICE_BIG_ENDIAN, > .valid = { > .min_access_size = 1, > Reviewed-by: Laurent Vivier <laurent@vivier.eu>
diff --git a/hw/nubus/nubus-bus.c b/hw/nubus/nubus-bus.c index 39182db065..a617459a4f 100644 --- a/hw/nubus/nubus-bus.c +++ b/hw/nubus/nubus-bus.c @@ -20,23 +20,23 @@ static NubusBus *nubus_find(void) return NUBUS_BUS(object_resolve_path_type("", TYPE_NUBUS_BUS, NULL)); } -static void nubus_slot_write(void *opaque, hwaddr addr, uint64_t val, - unsigned int size) +static MemTxResult nubus_slot_write(void *opaque, hwaddr addr, uint64_t val, + unsigned size, MemTxAttrs attrs) { - /* read only */ trace_nubus_slot_write(addr, val, size); + return MEMTX_DECODE_ERROR; } -static uint64_t nubus_slot_read(void *opaque, hwaddr addr, - unsigned int size) +static MemTxResult nubus_slot_read(void *opaque, hwaddr addr, uint64_t *data, + unsigned size, MemTxAttrs attrs) { trace_nubus_slot_read(addr, size); - return 0; + return MEMTX_DECODE_ERROR; } static const MemoryRegionOps nubus_slot_ops = { - .read = nubus_slot_read, - .write = nubus_slot_write, + .read_with_attrs = nubus_slot_read, + .write_with_attrs = nubus_slot_write, .endianness = DEVICE_BIG_ENDIAN, .valid = { .min_access_size = 1, @@ -44,23 +44,25 @@ static const MemoryRegionOps nubus_slot_ops = { }, }; -static void nubus_super_slot_write(void *opaque, hwaddr addr, uint64_t val, - unsigned int size) +static MemTxResult nubus_super_slot_write(void *opaque, hwaddr addr, + uint64_t val, unsigned size, + MemTxAttrs attrs) { - /* read only */ trace_nubus_super_slot_write(addr, val, size); + return MEMTX_DECODE_ERROR; } -static uint64_t nubus_super_slot_read(void *opaque, hwaddr addr, - unsigned int size) +static MemTxResult nubus_super_slot_read(void *opaque, hwaddr addr, + uint64_t *data, unsigned size, + MemTxAttrs attrs) { trace_nubus_super_slot_read(addr, size); - return 0; + return MEMTX_DECODE_ERROR; } static const MemoryRegionOps nubus_super_slot_ops = { - .read = nubus_super_slot_read, - .write = nubus_super_slot_write, + .read_with_attrs = nubus_super_slot_read, + .write_with_attrs = nubus_super_slot_write, .endianness = DEVICE_BIG_ENDIAN, .valid = { .min_access_size = 1,
According to "Designing Cards and Drivers for the Macintosh Family" any attempt to access an unimplemented address location on Nubus generates a bus error. MacOS uses a custom bus error handler to detect empty Nubus slots, and with the current implementation assumes that all slots are occupied as the Nubus transactions never fail. Switch nubus_slot_ops and nubus_super_slot_ops over to use {read,write}_with_attrs and hard-code them to return MEMTX_DECODE_ERROR so that unoccupied Nubus slots will generate the expected bus error. Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk> Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org> --- hw/nubus/nubus-bus.c | 34 ++++++++++++++++++---------------- 1 file changed, 18 insertions(+), 16 deletions(-)