On 02/16/2010 02:35 AM, Frediano Ziglio wrote:
Add a QEMU timer only when needed (timeout status not set, timeout
irq wanted and timer set).
This patch is required for Darwin. Patch has been tested under
FreeBSD, Darwin and Linux.
Signed-off-by: Frediano Ziglio<fredd...@gmail.com>
---
hw/rtl8139.c | 136 ++++++++++++++++++++++++++++++++++-----------------------
1 files changed, 81 insertions(+), 55 deletions(-)
diff --git a/hw/rtl8139.c b/hw/rtl8139.c
index f04dd54..e43c15c 100644
--- a/hw/rtl8139.c
+++ b/hw/rtl8139.c
@@ -41,6 +41,10 @@
* segmentation offloading
* Removed slirp.h dependency
* Added rx/tx buffer reset when enabling
rx/tx operation
+ *
+ * 2010-Feb-04 Frediano Ziglio: Rewrote timer support using QEMU timer only
+ * when strictly needed (required for for
+ * Darwin)
*/
#include "hw.h"
@@ -60,9 +64,6 @@
/* Calculate CRCs properly on Rx packets */
#define RTL8139_CALCULATE_RXCRC 1
-/* Uncomment to enable on-board timer interrupts */
-//#define RTL8139_ONBOARD_TIMER 1
-
#if defined(RTL8139_CALCULATE_RXCRC)
/* For crc32 */
#include<zlib.h>
@@ -491,9 +492,12 @@ typedef struct RTL8139State {
/* PCI interrupt timer */
QEMUTimer *timer;
+ int64_t TimerExpire;
} RTL8139State;
+static void rtl8139_set_next_tctr_time(RTL8139State *s, int64_t current_time);
+
static void prom9346_decode_command(EEprom9346 *eeprom, uint8_t command)
{
DEBUG_PRINT(("RTL8139: eeprom command 0x%02x\n", command));
@@ -2522,7 +2526,9 @@ static void rtl8139_IntrMask_write(RTL8139State *s,
uint32_t val)
s->IntrMask = val;
+ rtl8139_set_next_tctr_time(s, qemu_get_clock(vm_clock));
rtl8139_update_irq(s);
+
}
static uint32_t rtl8139_IntrMask_read(RTL8139State *s)
@@ -2555,12 +2561,22 @@ static void rtl8139_IntrStatus_write(RTL8139State *s,
uint32_t val)
rtl8139_update_irq(s);
s->IntrStatus = newStatus;
+ /*
+ * Computing if we miss an interrupt here is not that correct but
+ * considered that we should have had already an interrupt
+ * and probably emulated is slower is better to assume this resetting was
+ * done before testing on previous rtl8139_update_irq lead to IRQ loosing
+ */
+ rtl8139_set_next_tctr_time(s, qemu_get_clock(vm_clock));
rtl8139_update_irq(s);
+
#endif
}
static uint32_t rtl8139_IntrStatus_read(RTL8139State *s)
{
+ rtl8139_set_next_tctr_time(s, qemu_get_clock(vm_clock));
+
uint32_t ret = s->IntrStatus;
DEBUG_PRINT(("RTL8139: IntrStatus read(w) val=0x%04x\n", ret));
@@ -2739,6 +2755,43 @@ static void rtl8139_io_writew(void *opaque, uint8_t
addr, uint32_t val)
}
}
+static void rtl8139_set_next_tctr_time(RTL8139State *s, int64_t current_time)
+{
+ DEBUG_PRINT(("RTL8139: entered rtl8139_set_next_tctr_time\n"));
+
+ if (s->TimerExpire&& current_time>= s->TimerExpire) {
+ s->IntrStatus |= PCSTimeout;
+ rtl8139_update_irq(s);
+ }
+
+ /* Set QEMU timer only if needed that is
+ * - TimerInt<> 0 (we have a timer)
+ * - mask = 1 (we want an interrupt timer)
+ * - irq = 0 (irq is not already active)
+ * If any of above change we need to compute timer again
+ * Also we must check if timer is passed without QEMU timer
+ */
+ s->TimerExpire = 0;
+ if (!s->TimerInt) {
+ return;
+ }
+
+ int64_t pci_time = muldiv64(current_time - s->TCTR_base, PCI_FREQUENCY,
+ get_ticks_per_sec());
+ uint32_t low_pci = pci_time& 0xffffffff;
Please don't mix variable declarations in code.
+ pci_time = pci_time - low_pci + s->TimerInt;
+ if (low_pci>= s->TimerInt) {
+ pci_time += 0x100000000LL;
+ }
+ int64_t next_time = s->TCTR_base + muldiv64(pci_time, get_ticks_per_sec(),
+ PCI_FREQUENCY);
+ s->TimerExpire = next_time;
+
+ if ((s->IntrMask& PCSTimeout) != 0&& (s->IntrStatus& PCSTimeout) == 0) {
+ qemu_mod_timer(s->timer, next_time);
+ }
+}
+
static void rtl8139_io_writel(void *opaque, uint8_t addr, uint32_t val)
{
RTL8139State *s = opaque;
@@ -2784,13 +2837,16 @@ static void rtl8139_io_writel(void *opaque, uint8_t
addr, uint32_t val)
case Timer:
DEBUG_PRINT(("RTL8139: TCTR Timer reset on write\n"));
- s->TCTR = 0;
s->TCTR_base = qemu_get_clock(vm_clock);
+ rtl8139_set_next_tctr_time(s, s->TCTR_base);
break;
case FlashReg:
DEBUG_PRINT(("RTL8139: FlashReg TimerInt write val=0x%08x\n",
val));
- s->TimerInt = val;
+ if (s->TimerInt != val) {
+ s->TimerInt = val;
+ rtl8139_set_next_tctr_time(s, qemu_get_clock(vm_clock));
+ }
break;
default:
@@ -3000,7 +3056,8 @@ static uint32_t rtl8139_io_readl(void *opaque, uint8_t
addr)
break;
case Timer:
- ret = s->TCTR;
+ ret = muldiv64(qemu_get_clock(vm_clock) - s->TCTR_base,
+ PCI_FREQUENCY, get_ticks_per_sec());
DEBUG_PRINT(("RTL8139: TCTR Timer read val=0x%08x\n", ret));
break;
@@ -3105,6 +3162,7 @@ static uint32_t rtl8139_mmio_readl(void *opaque,
target_phys_addr_t addr)
static int rtl8139_post_load(void *opaque, int version_id)
{
RTL8139State* s = opaque;
+ rtl8139_set_next_tctr_time(s, qemu_get_clock(vm_clock));
if (version_id< 4) {
s->cplus_enabled = s->CpCmd != 0;
}
@@ -3112,12 +3170,24 @@ static int rtl8139_post_load(void *opaque, int
version_id)
return 0;
}
+static void rtl8139_pre_save(void *opaque)
+{
+ RTL8139State* s = opaque;
+
+ // set IntrStatus correctly
Please avoid C99 comments.
+ int64_t current_time = qemu_get_clock(vm_clock);
+ rtl8139_set_next_tctr_time(s, current_time);
+ s->TCTR = muldiv64(current_time - s->TCTR_base, PCI_FREQUENCY,
+ get_ticks_per_sec());
+}
Usually, timers have to be saved as part of save/restore in order for
them to fire correctly when restarted. I suspect this breaks save/restore.
I'd like to see some performance data too. I'm concerned that a change
like this could have a significant impact on performance.
Regards,
Anthony Liguori
