m68k/atari: Reserve some ST-RAM early on for device buffer use

Based on an original patch from Michael Schmitz:

Because mem_init() is now called before device init, devices that rely on
ST-RAM may find all ST-RAM already allocated to other users by the time
device init happens. In particular, a large initrd RAM disk may use up
enough of ST-RAM to cause atari_stram_alloc() to resort to
__get_dma_pages() allocation.

In the current state of Atari memory management, all of RAM is marked
DMA capable, so __get_dma_pages() may well return RAM that is not in actual
fact DMA capable. Using this for frame buffer or SCSI DMA buffer causes
subtle failure.

The ST-RAM allocator has been changed to allocate memory from a pool of
reserved ST-RAM of configurable size, set aside on ST-RAM init (i.e.
before mem_init()). As long as this pool is not exhausted, allocation of
real ST-RAM can be guaranteed.

Other changes:
  - Replace the custom allocator in the ST-RAM pool by the existing allocator
    in the resource subsystem,
  - Remove mem_init_done and its hook, as memory init is now done before
    device init,
  - Remove /proc/stram, as ST-RAM usage now shows up under /proc/iomem, e.g.

	005f2000-006f1fff : ST-RAM Pool
	  005f2000-0063dfff : atafb
	  0063e000-00641fff : ataflop
	  00642000-00642fff : SCSI

Signed-off-by: Michael Schmitz <schmitz@debian.org>
[Andreas Schwab <schwab@linux-m68k.org>: Use memparse()]
[Geert: Use the resource subsystem instead of a custom allocator]
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>

1 files changed, 0 insertions, 5 deletions

diff --git a/arch/m68k/mm/init_mm.c b/arch/m68k/mm/init_mm.c
index 9113c2f..bbe5254 100644
--- a/arch/m68k/mm/init_mm.c
+++ b/arch/m68k/mm/init_mm.c
@@ -83,11 +83,6 @@ void __init mem_init(void)
 	int initpages = 0;
 	int i;
 
-#ifdef CONFIG_ATARI
-	if (MACH_IS_ATARI)
-		atari_stram_mem_init_hook();
-#endif
-
 	/* this will put all memory onto the freelists */
 	totalram_pages = num_physpages = 0;
 	for_each_online_pgdat(pgdat) {