diff options
Diffstat (limited to 'drivers/scsi/sun3_NCR5380.c')
-rw-r--r-- | drivers/scsi/sun3_NCR5380.c | 58 |
1 files changed, 0 insertions, 58 deletions
diff --git a/drivers/scsi/sun3_NCR5380.c b/drivers/scsi/sun3_NCR5380.c index f3cffdf..7e12a2e 100644 --- a/drivers/scsi/sun3_NCR5380.c +++ b/drivers/scsi/sun3_NCR5380.c @@ -49,13 +49,6 @@ * inside the execution of NCR5380_intr(), leading to recursive * calls. * - * - I've added a function merge_contiguous_buffers() that tries to - * merge scatter-gather buffers that are located at contiguous - * physical addresses and can be processed with the same DMA setup. - * Since most scatter-gather operations work on a page (4K) of - * 4 buffers (1K), in more than 90% of all cases three interrupts and - * DMA setup actions are saved. - * * - I've deleted all the stuff for AUTOPROBE_IRQ, REAL_DMA_POLL, PSEUDO_DMA * and USLEEP, because these were messing up readability and will never be * needed for Atari SCSI. @@ -460,47 +453,6 @@ static void free_all_tags( void ) /* - * Function: void merge_contiguous_buffers(struct scsi_cmnd *cmd) - * - * Purpose: Try to merge several scatter-gather requests into one DMA - * transfer. This is possible if the scatter buffers lie on - * physical contiguous addresses. - * - * Parameters: struct scsi_cmnd *cmd - * The command to work on. The first scatter buffer's data are - * assumed to be already transferred into ptr/this_residual. - */ - -static void merge_contiguous_buffers(struct scsi_cmnd *cmd) -{ - unsigned long endaddr; -#if (NDEBUG & NDEBUG_MERGING) - unsigned long oldlen = cmd->SCp.this_residual; - int cnt = 1; -#endif - - for (endaddr = virt_to_phys(cmd->SCp.ptr + cmd->SCp.this_residual - 1) + 1; - cmd->SCp.buffers_residual && - virt_to_phys(SGADDR(&(cmd->SCp.buffer[1]))) == endaddr; ) { - - MER_PRINTK("VTOP(%p) == %08lx -> merging\n", - SGADDR(&(cmd->SCp.buffer[1])), endaddr); -#if (NDEBUG & NDEBUG_MERGING) - ++cnt; -#endif - ++cmd->SCp.buffer; - --cmd->SCp.buffers_residual; - cmd->SCp.this_residual += cmd->SCp.buffer->length; - endaddr += cmd->SCp.buffer->length; - } -#if (NDEBUG & NDEBUG_MERGING) - if (oldlen != cmd->SCp.this_residual) - MER_PRINTK("merged %d buffers from %p, new length %08x\n", - cnt, cmd->SCp.ptr, cmd->SCp.this_residual); -#endif -} - -/* * Function : void initialize_SCp(struct scsi_cmnd *cmd) * * Purpose : initialize the saved data pointers for cmd to point to the @@ -521,11 +473,6 @@ static __inline__ void initialize_SCp(struct scsi_cmnd *cmd) cmd->SCp.buffers_residual = scsi_sg_count(cmd) - 1; cmd->SCp.ptr = (char *) SGADDR(cmd->SCp.buffer); cmd->SCp.this_residual = cmd->SCp.buffer->length; - - /* ++roman: Try to merge some scatter-buffers if they are at - * contiguous physical addresses. - */ -// merge_contiguous_buffers( cmd ); } else { cmd->SCp.buffer = NULL; cmd->SCp.buffers_residual = 0; @@ -2076,11 +2023,6 @@ static void NCR5380_information_transfer (struct Scsi_Host *instance) --cmd->SCp.buffers_residual; cmd->SCp.this_residual = cmd->SCp.buffer->length; cmd->SCp.ptr = SGADDR(cmd->SCp.buffer); - - /* ++roman: Try to merge some scatter-buffers if - * they are at contiguous physical addresses. - */ -// merge_contiguous_buffers( cmd ); INF_PRINTK("scsi%d: %d bytes and %d buffers left\n", HOSTNO, cmd->SCp.this_residual, cmd->SCp.buffers_residual); |