On Thu, 16 Sep 2021, Mark Cave-Ayland wrote:
On 16/09/2021 13:48, BALATON Zoltan wrote:
On Thu, 16 Sep 2021, Mark Cave-Ayland wrote:
According to "Designing Cards and Drivers for the Macintosh Family" the
Nubus
has its own 32-bit address space based upon physical slot addressing.
Move Nubus to its own 32-bit address space and then use memory region
aliases
to map available slot and super slot ranges into the q800 system address
space via the Macintosh Nubus bridge.
Signed-off-by: Mark Cave-Ayland <mark.cave-ayl...@ilande.co.uk>
Reviewed-by: Philippe Mathieu-Daudé <f4...@amsat.org>
---
hw/m68k/q800.c | 8 +++-----
hw/nubus/mac-nubus-bridge.c | 15 +++++++++++++--
hw/nubus/nubus-bus.c | 18 ++++++++++++++++++
hw/nubus/nubus-device.c | 2 +-
include/hw/nubus/mac-nubus-bridge.h | 2 ++
include/hw/nubus/nubus.h | 10 +++++++---
6 files changed, 44 insertions(+), 11 deletions(-)
diff --git a/hw/m68k/q800.c b/hw/m68k/q800.c
index 5ba87f789c..0a0051a296 100644
--- a/hw/m68k/q800.c
+++ b/hw/m68k/q800.c
@@ -67,9 +67,6 @@
#define ASC_BASE (IO_BASE + 0x14000)
#define SWIM_BASE (IO_BASE + 0x1E000)
-#define NUBUS_SUPER_SLOT_BASE 0x60000000
-#define NUBUS_SLOT_BASE 0xf0000000
-
#define SONIC_PROM_SIZE 0x1000
/*
@@ -396,8 +393,9 @@ static void q800_init(MachineState *machine)
dev = qdev_new(TYPE_MAC_NUBUS_BRIDGE);
sysbus_realize_and_unref(SYS_BUS_DEVICE(dev), &error_fatal);
- sysbus_mmio_map(SYS_BUS_DEVICE(dev), 0, NUBUS_SUPER_SLOT_BASE);
- sysbus_mmio_map(SYS_BUS_DEVICE(dev), 1, NUBUS_SLOT_BASE);
+ sysbus_mmio_map(SYS_BUS_DEVICE(dev), 0, 9 * NUBUS_SUPER_SLOT_SIZE);
+ sysbus_mmio_map(SYS_BUS_DEVICE(dev), 1, NUBUS_SLOT_BASE +
+ 9 * NUBUS_SLOT_SIZE);
nubus = MAC_NUBUS_BRIDGE(dev)->bus;
diff --git a/hw/nubus/mac-nubus-bridge.c b/hw/nubus/mac-nubus-bridge.c
index c1d77e2bc7..574bc7831e 100644
--- a/hw/nubus/mac-nubus-bridge.c
+++ b/hw/nubus/mac-nubus-bridge.c
@@ -21,8 +21,19 @@ static void mac_nubus_bridge_init(Object *obj)
/* Macintosh only has slots 0x9 to 0xe available */
s->bus->slot_available_mask = MAKE_64BIT_MASK(9, 6);
- sysbus_init_mmio(sbd, &s->bus->super_slot_io);
- sysbus_init_mmio(sbd, &s->bus->slot_io);
+ /* Aliases for slots 0x9 to 0xe */
+ memory_region_init_alias(&s->super_slot_alias, obj,
"super-slot-alias",
+ &s->bus->nubus_mr,
+ 9 * NUBUS_SUPER_SLOT_SIZE,
+ 6 * NUBUS_SUPER_SLOT_SIZE);
Sorry for not spotting it yesterday in v2 but I only had time to have a
closer look now. Do these 9 and 6 worth a #define? Are these something like
MAC_FIST_SLOT and MAC_NUM_SLOTS? As they maybe always appear together with
NUBUS_SUPER_SLOT_SIZE (I haven't checked all but most look like that) so
those products could have a #define just to make it shorter in these calls.
(Are those the #defines that you've removed above?) Maybe
#define MAC_FIRST_SLOT 9
#define MAC_NUM_SLOTS 6
then use these to
#define MAC_SLOTS_MASK MAKE_64BIT_MASK(MAC_FIRST_SLOT, MAC_NUM_SLOTS)
and similarly the memory address and size as
#define MAC_SLOT_BASE 9 * NUBUS_SUPER_SLOT_SIZE #define MAC_SLOT_SIZE 6 *
NUBUS_SUPER_SLOT_SIZE
or so and then use these latter three where they appear now open coded
could be shorter and clearer but I don't mind either way so if you want to
keep the current version that's OK with me as well. (I may have got the
names for these wrong but hopefully you get the idea, I haven't tried to
understand in detail what these really are.)
Regards,
BALATON Zoltan
I'm not amazingly sold on this since it introduces another layer of
indirection: in its current form you can immediately correlate all of mask,
offset, and size with the comment without having to look up another set of
constants first.
As I said I'm OK with it as it as too.
Regards,
BALATON Zoltan
