add block write function to spartan3 slave serial load

Using seperate function calls for each bit-bang of slave serial
load can be painfully slow. This patch adds the possibility to
supply a block write function that loads the complete block of
data in one call (like it can already be done with Altera FPGAs).
On an MCF5373L (240 MHz) loading an XC3S4000 this reduces the load
time from around 15 seconds to around 3 seconds

Signed-off-by: Wolfgang Wegner <w.wegner at astro-kom.de>

1 files changed, 29 insertions, 25 deletions

diff --git a/drivers/fpga/spartan3.c b/drivers/fpga/spartan3.c
index 0fe3041..7a89b56 100644
--- a/drivers/fpga/spartan3.c
+++ b/drivers/fpga/spartan3.c
@@ -385,34 +385,38 @@ static int Spartan3_ss_load (Xilinx_desc * desc, void *buf, size_t bsize)
 		} while ((*fn->init) (cookie));
 
 		/* Load the data */
-		while (bytecount < bsize) {
-
-			/* Xilinx detects an error if INIT goes low (active)
-			   while DONE is low (inactive) */
-			if ((*fn->done) (cookie) == 0 && (*fn->init) (cookie)) {
-				puts ("** CRC error during FPGA load.\n");
-				return (FPGA_FAIL);
-			}
-			val = data [bytecount ++];
-			i = 8;
-			do {
-				/* Deassert the clock */
-				(*fn->clk) (FALSE, TRUE, cookie);
-				CONFIG_FPGA_DELAY ();
-				/* Write data */
-				(*fn->wr) ((val & 0x80), TRUE, cookie);
-				CONFIG_FPGA_DELAY ();
-				/* Assert the clock */
-				(*fn->clk) (TRUE, TRUE, cookie);
-				CONFIG_FPGA_DELAY ();
-				val <<= 1;
-				i --;
-			} while (i > 0);
+		if(*fn->bwr)
+			(*fn->bwr) (data, bsize, TRUE, cookie);
+		else {
+			while (bytecount < bsize) {
+
+				/* Xilinx detects an error if INIT goes low (active)
+				   while DONE is low (inactive) */
+				if ((*fn->done) (cookie) == 0 && (*fn->init) (cookie)) {
+					puts ("** CRC error during FPGA load.\n");
+					return (FPGA_FAIL);
+				}
+				val = data [bytecount ++];
+				i = 8;
+				do {
+					/* Deassert the clock */
+					(*fn->clk) (FALSE, TRUE, cookie);
+					CONFIG_FPGA_DELAY ();
+					/* Write data */
+					(*fn->wr) ((val & 0x80), TRUE, cookie);
+					CONFIG_FPGA_DELAY ();
+					/* Assert the clock */
+					(*fn->clk) (TRUE, TRUE, cookie);
+					CONFIG_FPGA_DELAY ();
+					val <<= 1;
+					i --;
+				} while (i > 0);
 
 #ifdef CONFIG_SYS_FPGA_PROG_FEEDBACK
-			if (bytecount % (bsize / 40) == 0)
-				putc ('.');		/* let them know we are alive */
+				if (bytecount % (bsize / 40) == 0)
+					putc ('.');		/* let them know we are alive */
 #endif
+			}
 		}
 
 		CONFIG_FPGA_DELAY ();