[OpenBIOS] r648 - in trunk/openbios-devel: arch/sparc64 drivers

[Blue Swirl]

On Wed, Dec 30, 2009 at 6:08 AM, Igor Kovalenko
<igor.v.kovalenko at gmail.com> wrote:
> On Wed, Dec 30, 2009 at 12:27 AM, Blue Swirl <blauwirbel at gmail.com> wrote:
>> On Tue, Dec 29, 2009 at 9:15 PM, Igor Kovalenko
>> <igor.v.kovalenko at gmail.com> wrote:
>>> On Mon, Dec 28, 2009 at 1:15 PM,  <svn at openbios.org> wrote:
>>>> Author: blueswirl
>>>> Date: 2009-12-28 11:15:33 +0100 (Mon, 28 Dec 2009)
>>>> New Revision: 648
>>>>
>>>> Modified:
>>>>   trunk/openbios-devel/arch/sparc64/entry.S
>>>>   trunk/openbios-devel/drivers/pci.c
>>>>   trunk/openbios-devel/drivers/vga_vbe.c
>>>> Log:
>>>> Map VGA buffer only during PCI probe
>>>>
>>>> Also pass physical addresses instead of bus addresses to VGA init.
>>>>
>>>> Signed-off-by: Blue Swirl <blauwirbel at gmail.com>
>>>>
>>>> Modified: trunk/openbios-devel/drivers/vga_vbe.c
>>>> ===================================================================
>>>> --- trunk/openbios-devel/drivers/vga_vbe.c      2009-12-21 09:57:53 UTC (rev 647)
>>>> +++ trunk/openbios-devel/drivers/vga_vbe.c      2009-12-28 10:15:33 UTC (rev 648)
>>>> @@ -25,6 +25,7 @@
>>>>  #include "asm/io.h"
>>>>  #include "libc/vsprintf.h"
>>>>  #include "video_subr.h"
>>>> +#include "ofmem.h"
>>>>
>>>>  /* VGA init. We use the Bochs VESA VBE extensions  */
>>>>  #define VBE_DISPI_INDEX_ID              0x0
>>>> @@ -142,7 +143,10 @@
>>>>                depth = d;
>>>>                linebytes = (width * ((depth + 7) / 8));
>>>>        }
>>>> +#ifdef CONFIG_SPARC64
>>>> +        ofmem_map_page_range(fb, fb, fb_size, 0x36);
>>>>  #endif
>>>> +#endif
>>>>
>>>>        vga_vbe_set_mode(width, height, depth);
>>>
>>> You pass flags so mapping is unlocked, this can cause
>>> problems with translations being evicted from tlb table.
>>> Do you see any issues? Linux kernel has it's own idea
>>> of address translations, and we still do not switch trap
>>> handlers so probably framebuffer should be mapped
>>> locked into tlb table (mode=0x76)
>>
>> If I use locked entries, with 8k pages there are soon no free TLB
>> entries left. I've tried to fix this with the attached patch which
>> adds support for 64k, 512k and 4M pages, then the entry can be changed
>> to locked one.
>>
>> However I get regressions with some tests. The new MMU entries created
>> by the miss handler look OK but Linux creates a bogus entry.
>
> You can use ofmem_map instead of ofmem_map_page_range
> to install locked entries. It uses ofmem_arch_early_map_pages
> so is able to install 4M locked entries as well. Something
> suggests we should use only page-sized unlocked translations.
>
> Also it would be good to provide framebuffer for client.
> Since client gets framebuffer address from device tree
> we are required to map framebuffer in 32bit space.
>
> The following change combines both suggestions.
> I think recent linux kernel would be now able to use
> framebuffer console driver.
>
> diff --git a/drivers/vga_vbe.c b/drivers/vga_vbe.c
> index 783125a..3c9b7b1 100644
> --- a/drivers/vga_vbe.c
> +++ b/drivers/vga_vbe.c
> @@ -144,7 +144,11 @@ void vga_vbe_init(const char *path, unsigned long
> fb, uint32_t fb_size,
>                linebytes = (width * ((depth + 7) / 8));
>        }
>  #ifdef CONFIG_SPARC64
> -        ofmem_map_page_range(fb, fb, fb_size, 0x36);
> +#define VGA_VADDR  0xfe000000
> +        ofmem_claim_phys(fb, fb_size, 0);
> +        ofmem_claim_virt(VGA_VADDR, fb_size, 0);
> +        ofmem_map(fb, VGA_VADDR, fb_size, 0x76);
> +        fb = VGA_VADDR;
>  #endif
>  #endif

That does help. I guess Linux gets confused with the 4M page entries.