[PULL 22/41] hw/char/pl011: Display register name in trace events

["Philippe Mathieu-Daudé" <philmd@linaro.org>]

To avoid knowing the register addresses by heart,
display their name along in the trace events.

Since the MMIO region is 4K wide (0x1000 bytes),
displaying the address with 3 digits is enough,
so reduce the address format.

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230522153144.30610-5-philmd@linaro.org>
---
 hw/char/pl011.c      | 25 ++++++++++++++++++++++---
 hw/char/trace-events |  4 ++--
 2 files changed, 24 insertions(+), 5 deletions(-)

diff --git a/hw/char/pl011.c b/hw/char/pl011.c
index 73f1a3aea2..c3203e5b41 100644
--- a/hw/char/pl011.c
+++ b/hw/char/pl011.c
@@ -51,6 +51,7 @@ DeviceState *pl011_create(hwaddr addr, qemu_irq irq, Chardev *chr)
 #define PL011_INT_TX 0x20
 #define PL011_INT_RX 0x10
 
+/* Flag Register, UARTFR */
 #define PL011_FLAG_TXFE 0x80
 #define PL011_FLAG_RXFF 0x40
 #define PL011_FLAG_TXFF 0x20
@@ -76,6 +77,24 @@ static const unsigned char pl011_id_arm[8] =
 static const unsigned char pl011_id_luminary[8] =
   { 0x11, 0x00, 0x18, 0x01, 0x0d, 0xf0, 0x05, 0xb1 };
 
+static const char *pl011_regname(hwaddr offset)
+{
+    static const char *const rname[] = {
+        [0] = "DR", [1] = "RSR", [6] = "FR", [8] = "ILPR", [9] = "IBRD",
+        [10] = "FBRD", [11] = "LCRH", [12] = "CR", [13] = "IFLS", [14] = "IMSC",
+        [15] = "RIS", [16] = "MIS", [17] = "ICR", [18] = "DMACR",
+    };
+    unsigned idx = offset >> 2;
+
+    if (idx < ARRAY_SIZE(rname) && rname[idx]) {
+        return rname[idx];
+    }
+    if (idx >= 0x3f8 && idx <= 0x400) {
+        return "ID";
+    }
+    return "UNKN";
+}
+
 /* Which bits in the interrupt status matter for each outbound IRQ line ? */
 static const uint32_t irqmask[] = {
     INT_E | INT_MS | INT_RT | INT_TX | INT_RX, /* combined IRQ */
@@ -191,7 +210,7 @@ static uint64_t pl011_read(void *opaque, hwaddr offset,
         break;
     }
 
-    trace_pl011_read(offset, r);
+    trace_pl011_read(offset, r, pl011_regname(offset));
     return r;
 }
 
@@ -234,7 +253,7 @@ static void pl011_write(void *opaque, hwaddr offset,
     PL011State *s = (PL011State *)opaque;
     unsigned char ch;
 
-    trace_pl011_write(offset, value);
+    trace_pl011_write(offset, value, pl011_regname(offset));
 
     switch (offset >> 2) {
     case 0: /* UARTDR */
@@ -252,7 +271,7 @@ static void pl011_write(void *opaque, hwaddr offset,
     case 6: /* UARTFR */
         /* Writes to Flag register are ignored.  */
         break;
-    case 8: /* UARTUARTILPR */
+    case 8: /* UARTILPR */
         s->ilpr = value;
         break;
     case 9: /* UARTIBRD */
diff --git a/hw/char/trace-events b/hw/char/trace-events
index 2ecb36232e..babf4d35ea 100644
--- a/hw/char/trace-events
+++ b/hw/char/trace-events
@@ -54,9 +54,9 @@ escc_sunmouse_event(int dx, int dy, int buttons_state) "dx=%d dy=%d buttons=0x%0
 
 # pl011.c
 pl011_irq_state(int level) "irq state %d"
-pl011_read(uint32_t addr, uint32_t value) "addr 0x%08x value 0x%08x"
+pl011_read(uint32_t addr, uint32_t value, const char *regname) "addr 0x%03x value 0x%08x reg %s"
 pl011_read_fifo(int read_count) "FIFO read, read_count now %d"
-pl011_write(uint32_t addr, uint32_t value) "addr 0x%08x value 0x%08x"
+pl011_write(uint32_t addr, uint32_t value, const char *regname) "addr 0x%03x value 0x%08x reg %s"
 pl011_can_receive(uint32_t lcr, int read_count, int r) "LCR 0x%08x read_count %d returning %d"
 pl011_put_fifo(uint32_t c, int read_count) "new char 0x%x read_count now %d"
 pl011_put_fifo_full(void) "FIFO now full, RXFF set"
-- 
2.41.0