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-rw-r--r--sound/isa/sb/emu8000.c31
1 files changed, 15 insertions, 16 deletions
diff --git a/sound/isa/sb/emu8000.c b/sound/isa/sb/emu8000.c
index 45fcdff611f9..d25e384fa8c9 100644
--- a/sound/isa/sb/emu8000.c
+++ b/sound/isa/sb/emu8000.c
@@ -378,13 +378,12 @@ init_arrays(struct snd_emu8000 *emu)
static void
size_dram(struct snd_emu8000 *emu)
{
- int i, size, detected_size;
+ int i, size;
if (emu->dram_checked)
return;
size = 0;
- detected_size = 0;
/* write out a magic number */
snd_emu8000_dma_chan(emu, 0, EMU8000_RAM_WRITE);
@@ -392,10 +391,19 @@ size_dram(struct snd_emu8000 *emu)
EMU8000_SMALW_WRITE(emu, EMU8000_DRAM_OFFSET);
EMU8000_SMLD_WRITE(emu, UNIQUE_ID1);
snd_emu8000_init_fm(emu); /* This must really be here and not 2 lines back even */
+ snd_emu8000_write_wait(emu);
- while (size < EMU8000_MAX_DRAM) {
+ /*
+ * Detect first 512 KiB. If a write succeeds at the beginning of a
+ * 512 KiB page we assume that the whole page is there.
+ */
+ EMU8000_SMALR_WRITE(emu, EMU8000_DRAM_OFFSET);
+ EMU8000_SMLD_READ(emu); /* discard stale data */
+ if (EMU8000_SMLD_READ(emu) != UNIQUE_ID1)
+ goto skip_detect; /* No RAM */
+ snd_emu8000_read_wait(emu);
- size += 512 * 1024; /* increment 512kbytes */
+ for (size = 512 * 1024; size < EMU8000_MAX_DRAM; size += 512 * 1024) {
/* Write a unique data on the test address.
* if the address is out of range, the data is written on
@@ -431,18 +439,9 @@ size_dram(struct snd_emu8000 *emu)
snd_emu8000_read_wait(emu);
/* Otherwise, it's valid memory. */
- detected_size = size + 512 * 1024;
- }
-
- /* Distinguish 512 KiB from 0. */
- if (detected_size == 0) {
- snd_emu8000_read_wait(emu);
- EMU8000_SMALR_WRITE(emu, EMU8000_DRAM_OFFSET);
- EMU8000_SMLD_READ(emu); /* discard stale data */
- if (EMU8000_SMLD_READ(emu) == UNIQUE_ID1)
- detected_size = 512 * 1024;
}
+skip_detect:
/* wait until FULL bit in SMAxW register is false */
for (i = 0; i < 10000; i++) {
if ((EMU8000_SMALW_READ(emu) & 0x80000000) == 0)
@@ -455,9 +454,9 @@ size_dram(struct snd_emu8000 *emu)
snd_emu8000_dma_chan(emu, 1, EMU8000_RAM_CLOSE);
snd_printdd("EMU8000 [0x%lx]: %d Kb on-board memory detected\n",
- emu->port1, detected_size/1024);
+ emu->port1, size/1024);
- emu->mem_size = detected_size;
+ emu->mem_size = size;
emu->dram_checked = 1;
}