From 959b373f8cdc2c1ad11c67c6916f88f48769438f Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?=C3=98yvind=20Harboe?= Date: Tue, 17 Nov 2009 11:03:55 +0100 Subject: jtag_registers: Avalon bridge flushing tweaks MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The code is now much more explicit. It flushes every N writes. For now flush every time, but tinkering with the bridge FIFO size and how often we flush clearly points in the direction of the Avalon write FIFO full being the culprit. Signed-off-by: Øyvind Harboe --- src/jtag/zy1000/jtag_minidriver.h | 13 ++++++++++++- 1 file changed, 12 insertions(+), 1 deletion(-) (limited to 'src') diff --git a/src/jtag/zy1000/jtag_minidriver.h b/src/jtag/zy1000/jtag_minidriver.h index 3fe16ef..afbea13 100644 --- a/src/jtag/zy1000/jtag_minidriver.h +++ b/src/jtag/zy1000/jtag_minidriver.h @@ -30,8 +30,19 @@ int diag_printf(const char *fmt, ...); #define ZY1000_POKE(a, b) HAL_WRITE_UINT32(a, b); diag_printf("poke 0x%08x,0x%08x\n", a, b) #define ZY1000_PEEK(a, b) HAL_READ_UINT32(a, b); diag_printf("peek 0x%08x = 0x%08x\n", a, b) #else -#define ZY1000_POKE(a, b) HAL_WRITE_UINT32(a, b) #define ZY1000_PEEK(a, b) HAL_READ_UINT32(a, b) +#define ZY1000_POKE(a, b) HAL_WRITE_UINT32(a, b);\ + {/* This will flush the bridge FIFO. Overflowed bridge FIFO fails. We must \ + flush every "often". No precise system has been found, but 4 seems solid. \ + */ \ + static int overflow_counter = 0; \ + if (++overflow_counter >= 1) \ + { \ + /* clear FIFO */ \ + cyg_uint32 empty; ZY1000_PEEK(ZY1000_JTAG_BASE + 0x10, empty); \ + overflow_counter = 0; \ + } \ + } #endif // FIFO empty? -- cgit v1.1