hw/mips/malta: Trace FPGA LEDs/ASCII display updates

The FPGA LEDs/ASCII display is mostly used by the bootloader
to show very low-level debug info. QEMU connects its output
to a character device backend, which is not very practical
to correlate with ASM instruction executed, interrupts or
MMIO accesses. Also, the display discard the previous states.

To ease bootloader debugging experience, add a pair of trace
events. Such events can be analyzed over time or diff-ed
between different runs.

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230104133935.4639-4-philmd@linaro.org>

diff --git a/hw/mips/malta.c b/hw/mips/malta.c
index e9424150aa564995c8cb5c85feca252127e5e3af..44d88a24a71d21ee3c603e8d58e0f92cdbf252cd 100644 (file)
--- a/hw/mips/malta.c
+++ b/hw/mips/malta.c
@@ -58,6 +58,7 @@
 #include "semihosting/semihost.h"
 #include "hw/mips/cps.h"
 #include "hw/qdev-clock.h"
+#include "trace.h"
 
 #define ENVP_PADDR          0x2000
 #define ENVP_VADDR          cpu_mips_phys_to_kseg0(NULL, ENVP_PADDR)
@@ -120,12 +121,14 @@ static void malta_fpga_update_display_leds(MaltaFPGAState *s)
     }
     leds_text[8] = '\0';
 
+    trace_malta_fpga_leds(leds_text);
     qemu_chr_fe_printf(&s->display, "\e[H\n\n|\e[32m%-8.8s\e[00m|\r\n",
                        leds_text);
 }
 
 static void malta_fpga_update_display_ascii(MaltaFPGAState *s)
 {
+    trace_malta_fpga_display(s->display_text);
     qemu_chr_fe_printf(&s->display, "\n\n\n\n|\e[31m%-8.8s\e[00m|",
                        s->display_text);
 }

diff --git a/hw/mips/trace-events b/hw/mips/trace-events
index 13ee731a4882d73ddd583c4b2dc68035d41a0aa6..b5b882c6c299f44df25e9158aeffb3d6101452a8 100644 (file)
--- a/hw/mips/trace-events
+++ b/hw/mips/trace-events
@@ -4,3 +4,7 @@ gt64120_write(uint64_t addr, uint64_t value) "gt64120 write 0x%03"PRIx64" value:
 gt64120_read_intreg(const char *regname, unsigned size, uint64_t value) "gt64120 read %s size:%u value:0x%08" PRIx64
 gt64120_write_intreg(const char *regname, unsigned size, uint64_t value) "gt64120 write %s size:%u value:0x%08" PRIx64
 gt64120_isd_remap(uint64_t from_length, uint64_t from_addr, uint64_t to_length, uint64_t to_addr) "ISD: 0x%08" PRIx64 "@0x%08" PRIx64 " -> 0x%08" PRIx64 "@0x%08" PRIx64
+
+# malta.c
+malta_fpga_leds(const char *text) "LEDs %s"
+malta_fpga_display(const char *text) "ASCII '%s'"