CUR_HORZ_OFF becomes non-zero when the cursor needs to be drawn to the left of the left edge of the frame buffer.
CUR_VERT_OFF is handled differently. When CUR_VERT_OFF is non-zero, CUR_OFFSET is changed to point to the first line of the cursor that will be drawn, so CUR_VERT_OFF is the number of lines to remove from the total height of the cursor.
Alternatively, we could handle CUR_VERT_OFF the same way as CUR_HORZ_OFF by leaving the cursor height constant, drawing the cursor starting from the CUR_VERT_OFF line, and adjusting cursor Y position by negative CUR_VERT_OFF.
This method is used by both pci_io_read and pci_io_write to determine if ISA type I/O access is allowed.
The SPARSE_IO_BASE I/O address is defined. This I/O range is not defined by an I/O BAR.
- Add IOBusDevice (nvram_addr_hi_dev) for NVRAM addr hi.
- Add IOBusDevice (nvram_dev) for NVRAM data.
- Make all IOBusDevices use the same code.
- Log error if 4 least significant bits of offset are not zero.
- Correctly byte swap the value before passing it to the IOBusDevice.
- When reading, duplicate the bytes in a word or dword like a real Power Mac does.
PDM defaults to 640x480.
If you set --mon_id to MacRGB12in then it would draw 512x384 inside a 640x480 window.
If you set --mon_id to Multiscan20in then it would try to draw 832x624 inside a 640x480 window and crash.
If you set the Monitors control panel to switch multiscan display from 640x480 to 832x624 and restart then it would crash.
Now it will correctly change the window size every time the mode changes.
Add pixel format and pixel clock to the list of fields that will initiate a recalculation.
If frame rate is less than 24 or greater than 120 then assume 60Hz.
Consider write-only bits: ATI_CLOCK_STROBE can't be read so clear it.
8 bits at Offset 2 is PLL_DATA. If we don't modify PLL_DATA, then insert the current value of PLL_DATA into the value that will be read from ATI_CLOCK_CNTL.
When checking if a particular byte of a register is accessed, check both the starting position (offset) and ending position (offset + size) of the bytes being access.