[PATCH V1 0/2] Fix the rtc issue on loongarch

[PATCH V1 0/2] Fix the rtc issue on loongarch

[Xianglai Li]

The first patch fixed the issue with rtc hardware
emulation on the loongarch platform.

The second patch adds an acpi table to the rtc hardware
simulation of the loongarch platform, enabling the virtual
machine kernel to use the loongson rtc driver through
the acpi table.

Cc: Bibo Mao <maobibo@loongson.cn>
Cc: Song Gao <gaosong@loongson.cn>
Cc: Jiaxun Yang <jiaxun.yang@flygoat.com>
Cc: Xianglai Li <lixianglai@loongson.cn>

Xianglai Li (2):
  hw/rtc: Fixed loongson rtc emulation errors
  hw/loongarch: add rtc acpi table

 hw/loongarch/virt-acpi-build.c | 24 ++++++++++++++++++++++++
 hw/loongarch/virt-fdt-build.c  | 11 +++++++++--
 hw/rtc/ls7a_rtc.c              | 26 +++++++++++++++++---------
 3 files changed, 50 insertions(+), 11 deletions(-)

-- 
2.39.1

[PATCH V1 1/2] hw/rtc: Fixed loongson rtc emulation errors

[Xianglai Li]

The expire time is sent to the timer only
when the expire Time is greater than 0 or
greater than now. Otherwise, the timer
will trigger interruption continuously.

Timer interrupts are sent using pulse functions.

Signed-off-by: Xianglai Li <lixianglai@loongson.cn>
---
Cc: Bibo Mao <maobibo@loongson.cn>
Cc: Song Gao <gaosong@loongson.cn>
Cc: Jiaxun Yang <jiaxun.yang@flygoat.com>
Cc: Xianglai Li <lixianglai@loongson.cn>

 hw/loongarch/virt-fdt-build.c | 11 +++++++++--
 hw/rtc/ls7a_rtc.c             | 26 +++++++++++++++++---------
 2 files changed, 26 insertions(+), 11 deletions(-)

diff --git a/hw/loongarch/virt-fdt-build.c b/hw/loongarch/virt-fdt-build.c
index 728ce46699..c613131a07 100644
--- a/hw/loongarch/virt-fdt-build.c
+++ b/hw/loongarch/virt-fdt-build.c
@@ -17,6 +17,11 @@
 #include "system/reset.h"
 #include "target/loongarch/cpu.h"
 
+#define FDT_IRQ_FLAGS_EDGE_LO_HI 1
+#define FDT_IRQ_FLAGS_EDGE_HI_LO 2
+#define FDT_IRQ_FLAGS_LEVEL_HI 4
+#define FDT_IRQ_FLAGS_LEVEL_LO 8
+
 static void create_fdt(LoongArchVirtMachineState *lvms)
 {
     MachineState *ms = MACHINE(lvms);
@@ -416,7 +421,8 @@ static void fdt_add_uart_node(LoongArchVirtMachineState *lvms,
     if (chosen) {
         qemu_fdt_setprop_string(ms->fdt, "/chosen", "stdout-path", nodename);
     }
-    qemu_fdt_setprop_cells(ms->fdt, nodename, "interrupts", irq, 0x4);
+    qemu_fdt_setprop_cells(ms->fdt, nodename, "interrupts", irq,
+                           FDT_IRQ_FLAGS_LEVEL_HI);
     qemu_fdt_setprop_cell(ms->fdt, nodename, "interrupt-parent",
                           *pch_pic_phandle);
     g_free(nodename);
@@ -436,7 +442,8 @@ static void fdt_add_rtc_node(LoongArchVirtMachineState *lvms,
                             "loongson,ls7a-rtc");
     qemu_fdt_setprop_sized_cells(ms->fdt, nodename, "reg", 2, base, 2, size);
     qemu_fdt_setprop_cells(ms->fdt, nodename, "interrupts",
-                           VIRT_RTC_IRQ - VIRT_GSI_BASE , 0x4);
+                           VIRT_RTC_IRQ - VIRT_GSI_BASE ,
+                           FDT_IRQ_FLAGS_EDGE_LO_HI);
     qemu_fdt_setprop_cell(ms->fdt, nodename, "interrupt-parent",
                           *pch_pic_phandle);
     g_free(nodename);
diff --git a/hw/rtc/ls7a_rtc.c b/hw/rtc/ls7a_rtc.c
index 10097b2db7..7eca75a42a 100644
--- a/hw/rtc/ls7a_rtc.c
+++ b/hw/rtc/ls7a_rtc.c
@@ -145,20 +145,24 @@ static void toymatch_write(LS7ARtcState *s, uint64_t val, int num)
         now = qemu_clock_get_ms(rtc_clock);
         toymatch_val_to_time(s, val, &tm);
         expire_time = now + (qemu_timedate_diff(&tm) - s->offset_toy) * 1000;
-        timer_mod(s->toy_timer[num], expire_time);
+        if (expire_time > now) {
+            timer_mod(s->toy_timer[num], expire_time);
+        }
     }
 }
 
 static void rtcmatch_write(LS7ARtcState *s, uint64_t val, int num)
 {
-    uint64_t expire_ns;
+    int64_t expire_ns;
 
     /* it do not support write when toy disabled */
     if (rtc_enabled(s)) {
         s->rtcmatch[num] = val;
         /* calculate expire time */
         expire_ns = ticks_to_ns(val) - ticks_to_ns(s->offset_rtc);
-        timer_mod_ns(s->rtc_timer[num], expire_ns);
+        if (expire_ns > 0) {
+            timer_mod_ns(s->rtc_timer[num], expire_ns);
+        }
     }
 }
 
@@ -185,7 +189,7 @@ static void ls7a_rtc_stop(LS7ARtcState *s)
 static void ls7a_toy_start(LS7ARtcState *s)
 {
     int i;
-    uint64_t expire_time, now;
+    int64_t expire_time, now;
     struct tm tm = {};
 
     now = qemu_clock_get_ms(rtc_clock);
@@ -194,19 +198,23 @@ static void ls7a_toy_start(LS7ARtcState *s)
     for (i = 0; i < TIMER_NUMS; i++) {
         toymatch_val_to_time(s, s->toymatch[i], &tm);
         expire_time = now + (qemu_timedate_diff(&tm) - s->offset_toy) * 1000;
-        timer_mod(s->toy_timer[i], expire_time);
+        if (expire_time > now) {
+            timer_mod(s->toy_timer[i], expire_time);
+        }
     }
 }
 
 static void ls7a_rtc_start(LS7ARtcState *s)
 {
     int i;
-    uint64_t expire_time;
+    int64_t expire_time;
 
     /* recalculate expire time and enable timer */
     for (i = 0; i < TIMER_NUMS; i++) {
         expire_time = ticks_to_ns(s->rtcmatch[i]) - ticks_to_ns(s->offset_rtc);
-        timer_mod_ns(s->rtc_timer[i], expire_time);
+        if (expire_time > 0) {
+            timer_mod_ns(s->rtc_timer[i], expire_time);
+        }
     }
 }
 
@@ -370,7 +378,7 @@ static void toy_timer_cb(void *opaque)
     LS7ARtcState *s = opaque;
 
     if (toy_enabled(s)) {
-        qemu_irq_raise(s->irq);
+        qemu_irq_pulse(s->irq);
     }
 }
 
@@ -379,7 +387,7 @@ static void rtc_timer_cb(void *opaque)
     LS7ARtcState *s = opaque;
 
     if (rtc_enabled(s)) {
-        qemu_irq_raise(s->irq);
+        qemu_irq_pulse(s->irq);
     }
 }
 
-- 
2.39.1

[PATCH V1 2/2] hw/loongarch: add rtc acpi table

[Xianglai Li]

Add the acpi table to the loongson rtc hardware
so that the virtual machine kernel can use the
loongson RTC-related drivers.

Signed-off-by: Xianglai Li <lixianglai@loongson.cn>
---
Cc: Bibo Mao <maobibo@loongson.cn>
Cc: Song Gao <gaosong@loongson.cn>
Cc: Jiaxun Yang <jiaxun.yang@flygoat.com>
Cc: Xianglai Li <lixianglai@loongson.cn>

 hw/loongarch/virt-acpi-build.c | 24 ++++++++++++++++++++++++
 1 file changed, 24 insertions(+)

diff --git a/hw/loongarch/virt-acpi-build.c b/hw/loongarch/virt-acpi-build.c
index 2cd2d9d842..2cfc5421c5 100644
--- a/hw/loongarch/virt-acpi-build.c
+++ b/hw/loongarch/virt-acpi-build.c
@@ -473,6 +473,29 @@ static void acpi_dsdt_add_tpm(Aml *scope, LoongArchVirtMachineState *vms)
 }
 #endif
 
+static void acpi_dsdt_add_rtc(Aml *scope)
+{
+    uint32_t rtc_irq = VIRT_RTC_IRQ;
+    Aml *dev = aml_device("RTC");
+
+    aml_append(dev, aml_name_decl("_HID", aml_string("LOON0001")));
+    aml_append(dev, aml_name_decl("_UID", aml_int(0)));
+
+    Aml *crs = aml_resource_template();
+    aml_append(crs,
+        aml_qword_memory(AML_POS_DECODE, AML_MIN_FIXED, AML_MAX_FIXED,
+                         AML_NON_CACHEABLE, AML_READ_WRITE,
+                         0, VIRT_RTC_REG_BASE,
+                         VIRT_RTC_REG_BASE + VIRT_RTC_LEN - 1,
+                         0, VIRT_RTC_LEN));
+    aml_append(crs,
+               aml_interrupt(AML_CONSUMER, AML_EDGE, AML_ACTIVE_HIGH,
+                             AML_EXCLUSIVE, &rtc_irq, 1));
+
+    aml_append(dev, aml_name_decl("_CRS", crs));
+    aml_append(scope, dev);
+}
+
 /* build DSDT */
 static void
 build_dsdt(GArray *table_data, BIOSLinker *linker, MachineState *machine)
@@ -488,6 +511,7 @@ build_dsdt(GArray *table_data, BIOSLinker *linker, MachineState *machine)
     for (i = 0; i < VIRT_UART_COUNT; i++) {
         build_uart_device_aml(dsdt, i);
     }
+    acpi_dsdt_add_rtc(dsdt);
     build_pci_device_aml(dsdt, lvms);
     build_la_ged_aml(dsdt, machine);
     build_flash_aml(dsdt, lvms);
-- 
2.39.1

Re: [PATCH V1 2/2] hw/loongarch: add rtc acpi table

[Bibo Mao]

Xianglai,

On 2025/6/13 上午9:31, Xianglai Li wrote:
> Add the acpi table to the loongson rtc hardware
> so that the virtual machine kernel can use the
> loongson RTC-related drivers.
One line of the comments is no more than 75 bytes, it seems that it is 
far less than 75 bytes.

> 
> Signed-off-by: Xianglai Li <lixianglai@loongson.cn>
> ---
> Cc: Bibo Mao <maobibo@loongson.cn>
> Cc: Song Gao <gaosong@loongson.cn>
> Cc: Jiaxun Yang <jiaxun.yang@flygoat.com>
> Cc: Xianglai Li <lixianglai@loongson.cn>
> 
>   hw/loongarch/virt-acpi-build.c | 24 ++++++++++++++++++++++++
>   1 file changed, 24 insertions(+)
> 
> diff --git a/hw/loongarch/virt-acpi-build.c b/hw/loongarch/virt-acpi-build.c
> index 2cd2d9d842..2cfc5421c5 100644
> --- a/hw/loongarch/virt-acpi-build.c
> +++ b/hw/loongarch/virt-acpi-build.c
> @@ -473,6 +473,29 @@ static void acpi_dsdt_add_tpm(Aml *scope, LoongArchVirtMachineState *vms)
>   }
>   #endif
>   
> +static void acpi_dsdt_add_rtc(Aml *scope)
> +{
> +    uint32_t rtc_irq = VIRT_RTC_IRQ;
> +    Aml *dev = aml_device("RTC");
> +
> +    aml_append(dev, aml_name_decl("_HID", aml_string("LOON0001")));
> +    aml_append(dev, aml_name_decl("_UID", aml_int(0)));
> +
> +    Aml *crs = aml_resource_template();
> +    aml_append(crs,
> +        aml_qword_memory(AML_POS_DECODE, AML_MIN_FIXED, AML_MAX_FIXED,
> +                         AML_NON_CACHEABLE, AML_READ_WRITE,
> +                         0, VIRT_RTC_REG_BASE,
> +                         VIRT_RTC_REG_BASE + VIRT_RTC_LEN - 1,
> +                         0, VIRT_RTC_LEN));
> +    aml_append(crs,
> +               aml_interrupt(AML_CONSUMER, AML_EDGE, AML_ACTIVE_HIGH,
> +                             AML_EXCLUSIVE, &rtc_irq, 1));
> +
> +    aml_append(dev, aml_name_decl("_CRS", crs));
> +    aml_append(scope, dev);
> +}
> +
>   /* build DSDT */
>   static void
>   build_dsdt(GArray *table_data, BIOSLinker *linker, MachineState *machine)
> @@ -488,6 +511,7 @@ build_dsdt(GArray *table_data, BIOSLinker *linker, MachineState *machine)
>       for (i = 0; i < VIRT_UART_COUNT; i++) {
>           build_uart_device_aml(dsdt, i);
>       }
> +    acpi_dsdt_add_rtc(dsdt);
>       build_pci_device_aml(dsdt, lvms);
>       build_la_ged_aml(dsdt, machine);
>       build_flash_aml(dsdt, lvms);
> 
Otherwise looks good to me except comments alignment.

Reviewed-by: Bibo Mao <maobibo@loongson.cn>

Re: [PATCH V1 1/2] hw/rtc: Fixed loongson rtc emulation errors

[Bibo Mao]

On 2025/6/13 上午9:31, Xianglai Li wrote:
> The expire time is sent to the timer only
> when the expire Time is greater than 0 or
> greater than now. Otherwise, the timer
> will trigger interruption continuously.
Again, one line of the comments should no more than 75 bytes :)

I think it should be split into two patches, one is fixup with irq pulse 
type setting, the other is fixup with expired time out calculation in 
rtc emulation driver.

Regards
Bibo Mao
> 
> Timer interrupts are sent using pulse functions.

> 
> Signed-off-by: Xianglai Li <lixianglai@loongson.cn>
> ---
> Cc: Bibo Mao <maobibo@loongson.cn>
> Cc: Song Gao <gaosong@loongson.cn>
> Cc: Jiaxun Yang <jiaxun.yang@flygoat.com>
> Cc: Xianglai Li <lixianglai@loongson.cn>
> 
>   hw/loongarch/virt-fdt-build.c | 11 +++++++++--
>   hw/rtc/ls7a_rtc.c             | 26 +++++++++++++++++---------
>   2 files changed, 26 insertions(+), 11 deletions(-)
> 
> diff --git a/hw/loongarch/virt-fdt-build.c b/hw/loongarch/virt-fdt-build.c
> index 728ce46699..c613131a07 100644
> --- a/hw/loongarch/virt-fdt-build.c
> +++ b/hw/loongarch/virt-fdt-build.c
> @@ -17,6 +17,11 @@
>   #include "system/reset.h"
>   #include "target/loongarch/cpu.h"
>   
> +#define FDT_IRQ_FLAGS_EDGE_LO_HI 1
> +#define FDT_IRQ_FLAGS_EDGE_HI_LO 2
> +#define FDT_IRQ_FLAGS_LEVEL_HI 4
> +#define FDT_IRQ_FLAGS_LEVEL_LO 8
> +
>   static void create_fdt(LoongArchVirtMachineState *lvms)
>   {
>       MachineState *ms = MACHINE(lvms);
> @@ -416,7 +421,8 @@ static void fdt_add_uart_node(LoongArchVirtMachineState *lvms,
>       if (chosen) {
>           qemu_fdt_setprop_string(ms->fdt, "/chosen", "stdout-path", nodename);
>       }
> -    qemu_fdt_setprop_cells(ms->fdt, nodename, "interrupts", irq, 0x4);
> +    qemu_fdt_setprop_cells(ms->fdt, nodename, "interrupts", irq,
> +                           FDT_IRQ_FLAGS_LEVEL_HI);
>       qemu_fdt_setprop_cell(ms->fdt, nodename, "interrupt-parent",
>                             *pch_pic_phandle);
>       g_free(nodename);
> @@ -436,7 +442,8 @@ static void fdt_add_rtc_node(LoongArchVirtMachineState *lvms,
>                               "loongson,ls7a-rtc");
>       qemu_fdt_setprop_sized_cells(ms->fdt, nodename, "reg", 2, base, 2, size);
>       qemu_fdt_setprop_cells(ms->fdt, nodename, "interrupts",
> -                           VIRT_RTC_IRQ - VIRT_GSI_BASE , 0x4);
> +                           VIRT_RTC_IRQ - VIRT_GSI_BASE ,
> +                           FDT_IRQ_FLAGS_EDGE_LO_HI);
>       qemu_fdt_setprop_cell(ms->fdt, nodename, "interrupt-parent",
>                             *pch_pic_phandle);
>       g_free(nodename);
> diff --git a/hw/rtc/ls7a_rtc.c b/hw/rtc/ls7a_rtc.c
> index 10097b2db7..7eca75a42a 100644
> --- a/hw/rtc/ls7a_rtc.c
> +++ b/hw/rtc/ls7a_rtc.c
> @@ -145,20 +145,24 @@ static void toymatch_write(LS7ARtcState *s, uint64_t val, int num)
>           now = qemu_clock_get_ms(rtc_clock);
>           toymatch_val_to_time(s, val, &tm);
>           expire_time = now + (qemu_timedate_diff(&tm) - s->offset_toy) * 1000;
> -        timer_mod(s->toy_timer[num], expire_time);
> +        if (expire_time > now) {
> +            timer_mod(s->toy_timer[num], expire_time);
> +        }
>       }
>   }
>   
>   static void rtcmatch_write(LS7ARtcState *s, uint64_t val, int num)
>   {
> -    uint64_t expire_ns;
> +    int64_t expire_ns;
>   
>       /* it do not support write when toy disabled */
>       if (rtc_enabled(s)) {
>           s->rtcmatch[num] = val;
>           /* calculate expire time */
>           expire_ns = ticks_to_ns(val) - ticks_to_ns(s->offset_rtc);
> -        timer_mod_ns(s->rtc_timer[num], expire_ns);
> +        if (expire_ns > 0) {
> +            timer_mod_ns(s->rtc_timer[num], expire_ns);
> +        }
>       }
>   }
>   
> @@ -185,7 +189,7 @@ static void ls7a_rtc_stop(LS7ARtcState *s)
>   static void ls7a_toy_start(LS7ARtcState *s)
>   {
>       int i;
> -    uint64_t expire_time, now;
> +    int64_t expire_time, now;
>       struct tm tm = {};
>   
>       now = qemu_clock_get_ms(rtc_clock);
> @@ -194,19 +198,23 @@ static void ls7a_toy_start(LS7ARtcState *s)
>       for (i = 0; i < TIMER_NUMS; i++) {
>           toymatch_val_to_time(s, s->toymatch[i], &tm);
>           expire_time = now + (qemu_timedate_diff(&tm) - s->offset_toy) * 1000;
> -        timer_mod(s->toy_timer[i], expire_time);
> +        if (expire_time > now) {
> +            timer_mod(s->toy_timer[i], expire_time);
> +        }
>       }
>   }
>   
>   static void ls7a_rtc_start(LS7ARtcState *s)
>   {
>       int i;
> -    uint64_t expire_time;
> +    int64_t expire_time;
>   
>       /* recalculate expire time and enable timer */
>       for (i = 0; i < TIMER_NUMS; i++) {
>           expire_time = ticks_to_ns(s->rtcmatch[i]) - ticks_to_ns(s->offset_rtc);
> -        timer_mod_ns(s->rtc_timer[i], expire_time);
> +        if (expire_time > 0) {
> +            timer_mod_ns(s->rtc_timer[i], expire_time);
> +        }
>       }
>   }
>   
> @@ -370,7 +378,7 @@ static void toy_timer_cb(void *opaque)
>       LS7ARtcState *s = opaque;
>   
>       if (toy_enabled(s)) {
> -        qemu_irq_raise(s->irq);
> +        qemu_irq_pulse(s->irq);
>       }
>   }
>   
> @@ -379,7 +387,7 @@ static void rtc_timer_cb(void *opaque)
>       LS7ARtcState *s = opaque;
>   
>       if (rtc_enabled(s)) {
> -        qemu_irq_raise(s->irq);
> +        qemu_irq_pulse(s->irq);
>       }
>   }
>   
> 

Re: [PATCH V1 1/2] hw/rtc: Fixed loongson rtc emulation errors

[Bibo Mao]

On 2025/6/13 上午9:31, Xianglai Li wrote:
> The expire time is sent to the timer only
> when the expire Time is greater than 0 or
> greater than now. Otherwise, the timer
> will trigger interruption continuously.
> 
> Timer interrupts are sent using pulse functions.
> 
> Signed-off-by: Xianglai Li <lixianglai@loongson.cn>
> ---
> Cc: Bibo Mao <maobibo@loongson.cn>
> Cc: Song Gao <gaosong@loongson.cn>
> Cc: Jiaxun Yang <jiaxun.yang@flygoat.com>
> Cc: Xianglai Li <lixianglai@loongson.cn>
> 
>   hw/loongarch/virt-fdt-build.c | 11 +++++++++--
>   hw/rtc/ls7a_rtc.c             | 26 +++++++++++++++++---------
>   2 files changed, 26 insertions(+), 11 deletions(-)
> 
> diff --git a/hw/loongarch/virt-fdt-build.c b/hw/loongarch/virt-fdt-build.c
> index 728ce46699..c613131a07 100644
> --- a/hw/loongarch/virt-fdt-build.c
> +++ b/hw/loongarch/virt-fdt-build.c
> @@ -17,6 +17,11 @@
>   #include "system/reset.h"
>   #include "target/loongarch/cpu.h"
>   
> +#define FDT_IRQ_FLAGS_EDGE_LO_HI 1
> +#define FDT_IRQ_FLAGS_EDGE_HI_LO 2
> +#define FDT_IRQ_FLAGS_LEVEL_HI 4
> +#define FDT_IRQ_FLAGS_LEVEL_LO 8
> +
>   static void create_fdt(LoongArchVirtMachineState *lvms)
>   {
>       MachineState *ms = MACHINE(lvms);
> @@ -416,7 +421,8 @@ static void fdt_add_uart_node(LoongArchVirtMachineState *lvms,
>       if (chosen) {
>           qemu_fdt_setprop_string(ms->fdt, "/chosen", "stdout-path", nodename);
>       }
> -    qemu_fdt_setprop_cells(ms->fdt, nodename, "interrupts", irq, 0x4);
> +    qemu_fdt_setprop_cells(ms->fdt, nodename, "interrupts", irq,
> +                           FDT_IRQ_FLAGS_LEVEL_HI);
>       qemu_fdt_setprop_cell(ms->fdt, nodename, "interrupt-parent",
>                             *pch_pic_phandle);
>       g_free(nodename);
> @@ -436,7 +442,8 @@ static void fdt_add_rtc_node(LoongArchVirtMachineState *lvms,
>                               "loongson,ls7a-rtc");
>       qemu_fdt_setprop_sized_cells(ms->fdt, nodename, "reg", 2, base, 2, size);
>       qemu_fdt_setprop_cells(ms->fdt, nodename, "interrupts",
> -                           VIRT_RTC_IRQ - VIRT_GSI_BASE , 0x4);
> +                           VIRT_RTC_IRQ - VIRT_GSI_BASE ,
> +                           FDT_IRQ_FLAGS_EDGE_LO_HI);
>       qemu_fdt_setprop_cell(ms->fdt, nodename, "interrupt-parent",
>                             *pch_pic_phandle);
>       g_free(nodename);
> diff --git a/hw/rtc/ls7a_rtc.c b/hw/rtc/ls7a_rtc.c
> index 10097b2db7..7eca75a42a 100644
> --- a/hw/rtc/ls7a_rtc.c
> +++ b/hw/rtc/ls7a_rtc.c
> @@ -145,20 +145,24 @@ static void toymatch_write(LS7ARtcState *s, uint64_t val, int num)
>           now = qemu_clock_get_ms(rtc_clock);
>           toymatch_val_to_time(s, val, &tm);
>           expire_time = now + (qemu_timedate_diff(&tm) - s->offset_toy) * 1000;
> -        timer_mod(s->toy_timer[num], expire_time);
> +        if (expire_time > now) {
> +            timer_mod(s->toy_timer[num], expire_time);
> +        }
Should rtc alarm interrupt be injected directly if (expire_time <= now)?

Regards
Bibo Mao
>       }
>   }
>   
>   static void rtcmatch_write(LS7ARtcState *s, uint64_t val, int num)
>   {
> -    uint64_t expire_ns;
> +    int64_t expire_ns;
>   
>       /* it do not support write when toy disabled */
>       if (rtc_enabled(s)) {
>           s->rtcmatch[num] = val;
>           /* calculate expire time */
>           expire_ns = ticks_to_ns(val) - ticks_to_ns(s->offset_rtc);
> -        timer_mod_ns(s->rtc_timer[num], expire_ns);
> +        if (expire_ns > 0) {
> +            timer_mod_ns(s->rtc_timer[num], expire_ns);
> +        }
>       }
>   }
>   
> @@ -185,7 +189,7 @@ static void ls7a_rtc_stop(LS7ARtcState *s)
>   static void ls7a_toy_start(LS7ARtcState *s)
>   {
>       int i;
> -    uint64_t expire_time, now;
> +    int64_t expire_time, now;
>       struct tm tm = {};
>   
>       now = qemu_clock_get_ms(rtc_clock);
> @@ -194,19 +198,23 @@ static void ls7a_toy_start(LS7ARtcState *s)
>       for (i = 0; i < TIMER_NUMS; i++) {
>           toymatch_val_to_time(s, s->toymatch[i], &tm);
>           expire_time = now + (qemu_timedate_diff(&tm) - s->offset_toy) * 1000;
> -        timer_mod(s->toy_timer[i], expire_time);
> +        if (expire_time > now) {
> +            timer_mod(s->toy_timer[i], expire_time);
> +        }
>       }
>   }
>   
>   static void ls7a_rtc_start(LS7ARtcState *s)
>   {
>       int i;
> -    uint64_t expire_time;
> +    int64_t expire_time;
>   
>       /* recalculate expire time and enable timer */
>       for (i = 0; i < TIMER_NUMS; i++) {
>           expire_time = ticks_to_ns(s->rtcmatch[i]) - ticks_to_ns(s->offset_rtc);
> -        timer_mod_ns(s->rtc_timer[i], expire_time);
> +        if (expire_time > 0) {
> +            timer_mod_ns(s->rtc_timer[i], expire_time);
> +        }
>       }
>   }
>   
> @@ -370,7 +378,7 @@ static void toy_timer_cb(void *opaque)
>       LS7ARtcState *s = opaque;
>   
>       if (toy_enabled(s)) {
> -        qemu_irq_raise(s->irq);
> +        qemu_irq_pulse(s->irq);
>       }
>   }
>   
> @@ -379,7 +387,7 @@ static void rtc_timer_cb(void *opaque)
>       LS7ARtcState *s = opaque;
>   
>       if (rtc_enabled(s)) {
> -        qemu_irq_raise(s->irq);
> +        qemu_irq_pulse(s->irq);
>       }
>   }
>   
> 

Re: [PATCH V1 2/2] hw/loongarch: add rtc acpi table

[Bibo Mao]

On 2025/6/13 上午9:31, Xianglai Li wrote:
> Add the acpi table to the loongson rtc hardware
> so that the virtual machine kernel can use the
> loongson RTC-related drivers.
> 
> Signed-off-by: Xianglai Li <lixianglai@loongson.cn>
> ---
> Cc: Bibo Mao <maobibo@loongson.cn>
> Cc: Song Gao <gaosong@loongson.cn>
> Cc: Jiaxun Yang <jiaxun.yang@flygoat.com>
> Cc: Xianglai Li <lixianglai@loongson.cn>
> 
>   hw/loongarch/virt-acpi-build.c | 24 ++++++++++++++++++++++++
>   1 file changed, 24 insertions(+)
> 
> diff --git a/hw/loongarch/virt-acpi-build.c b/hw/loongarch/virt-acpi-build.c
> index 2cd2d9d842..2cfc5421c5 100644
> --- a/hw/loongarch/virt-acpi-build.c
> +++ b/hw/loongarch/virt-acpi-build.c
> @@ -473,6 +473,29 @@ static void acpi_dsdt_add_tpm(Aml *scope, LoongArchVirtMachineState *vms)
>   }
>   #endif
>   
> +static void acpi_dsdt_add_rtc(Aml *scope)
> +{
> +    uint32_t rtc_irq = VIRT_RTC_IRQ;
> +    Aml *dev = aml_device("RTC");
> +
> +    aml_append(dev, aml_name_decl("_HID", aml_string("LOON0001")));
> +    aml_append(dev, aml_name_decl("_UID", aml_int(0)));
> +
> +    Aml *crs = aml_resource_template();
> +    aml_append(crs,
> +        aml_qword_memory(AML_POS_DECODE, AML_MIN_FIXED, AML_MAX_FIXED,
> +                         AML_NON_CACHEABLE, AML_READ_WRITE,
> +                         0, VIRT_RTC_REG_BASE,
> +                         VIRT_RTC_REG_BASE + VIRT_RTC_LEN - 1,
> +                         0, VIRT_RTC_LEN));
> +    aml_append(crs,
> +               aml_interrupt(AML_CONSUMER, AML_EDGE, AML_ACTIVE_HIGH,
> +                             AML_EXCLUSIVE, &rtc_irq, 1));
> +
> +    aml_append(dev, aml_name_decl("_CRS", crs));
> +    aml_append(scope, dev);
> +}
> +
The rtc loongson driver drivers/rtc/rtc-loongson.c is bond with acpi pm1 
device since rtc device is wake-up source on physical machine, however 
acpi ged device rather than pm1 device is used on virt machine.

I think firstly we should submit patch to rtc loongson driver 
drivers/rtc/rtc-loongson.c so that it supports non acpi pm1 device, then 
submit rtc acpi dsdt table.

Regards
Bibo Mao
>   /* build DSDT */
>   static void
>   build_dsdt(GArray *table_data, BIOSLinker *linker, MachineState *machine)
> @@ -488,6 +511,7 @@ build_dsdt(GArray *table_data, BIOSLinker *linker, MachineState *machine)
>       for (i = 0; i < VIRT_UART_COUNT; i++) {
>           build_uart_device_aml(dsdt, i);
>       }
> +    acpi_dsdt_add_rtc(dsdt);
>       build_pci_device_aml(dsdt, lvms);
>       build_la_ged_aml(dsdt, machine);
>       build_flash_aml(dsdt, lvms);
> 

Re: [PATCH V1 1/2] hw/rtc: Fixed loongson rtc emulation errors

[lixianglai]

Hi Bibo Mao:
>
>
> On 2025/6/13 上午9:31, Xianglai Li wrote:
>> The expire time is sent to the timer only
>> when the expire Time is greater than 0 or
>> greater than now. Otherwise, the timer
>> will trigger interruption continuously.
>>
>> Timer interrupts are sent using pulse functions.
>>
>> Signed-off-by: Xianglai Li <lixianglai@loongson.cn>
>> ---
>> Cc: Bibo Mao <maobibo@loongson.cn>
>> Cc: Song Gao <gaosong@loongson.cn>
>> Cc: Jiaxun Yang <jiaxun.yang@flygoat.com>
>> Cc: Xianglai Li <lixianglai@loongson.cn>
>>
>>   hw/loongarch/virt-fdt-build.c | 11 +++++++++--
>>   hw/rtc/ls7a_rtc.c             | 26 +++++++++++++++++---------
>>   2 files changed, 26 insertions(+), 11 deletions(-)
>>
>> diff --git a/hw/loongarch/virt-fdt-build.c 
>> b/hw/loongarch/virt-fdt-build.c
>> index 728ce46699..c613131a07 100644
>> --- a/hw/loongarch/virt-fdt-build.c
>> +++ b/hw/loongarch/virt-fdt-build.c
>> @@ -17,6 +17,11 @@
>>   #include "system/reset.h"
>>   #include "target/loongarch/cpu.h"
>>   +#define FDT_IRQ_FLAGS_EDGE_LO_HI 1
>> +#define FDT_IRQ_FLAGS_EDGE_HI_LO 2
>> +#define FDT_IRQ_FLAGS_LEVEL_HI 4
>> +#define FDT_IRQ_FLAGS_LEVEL_LO 8
>> +
>>   static void create_fdt(LoongArchVirtMachineState *lvms)
>>   {
>>       MachineState *ms = MACHINE(lvms);
>> @@ -416,7 +421,8 @@ static void 
>> fdt_add_uart_node(LoongArchVirtMachineState *lvms,
>>       if (chosen) {
>>           qemu_fdt_setprop_string(ms->fdt, "/chosen", "stdout-path", 
>> nodename);
>>       }
>> -    qemu_fdt_setprop_cells(ms->fdt, nodename, "interrupts", irq, 0x4);
>> +    qemu_fdt_setprop_cells(ms->fdt, nodename, "interrupts", irq,
>> +                           FDT_IRQ_FLAGS_LEVEL_HI);
>>       qemu_fdt_setprop_cell(ms->fdt, nodename, "interrupt-parent",
>>                             *pch_pic_phandle);
>>       g_free(nodename);
>> @@ -436,7 +442,8 @@ static void 
>> fdt_add_rtc_node(LoongArchVirtMachineState *lvms,
>>                               "loongson,ls7a-rtc");
>>       qemu_fdt_setprop_sized_cells(ms->fdt, nodename, "reg", 2, base, 
>> 2, size);
>>       qemu_fdt_setprop_cells(ms->fdt, nodename, "interrupts",
>> -                           VIRT_RTC_IRQ - VIRT_GSI_BASE , 0x4);
>> +                           VIRT_RTC_IRQ - VIRT_GSI_BASE ,
>> +                           FDT_IRQ_FLAGS_EDGE_LO_HI);
>>       qemu_fdt_setprop_cell(ms->fdt, nodename, "interrupt-parent",
>>                             *pch_pic_phandle);
>>       g_free(nodename);
>> diff --git a/hw/rtc/ls7a_rtc.c b/hw/rtc/ls7a_rtc.c
>> index 10097b2db7..7eca75a42a 100644
>> --- a/hw/rtc/ls7a_rtc.c
>> +++ b/hw/rtc/ls7a_rtc.c
>> @@ -145,20 +145,24 @@ static void toymatch_write(LS7ARtcState *s, 
>> uint64_t val, int num)
>>           now = qemu_clock_get_ms(rtc_clock);
>>           toymatch_val_to_time(s, val, &tm);
>>           expire_time = now + (qemu_timedate_diff(&tm) - 
>> s->offset_toy) * 1000;
>> -        timer_mod(s->toy_timer[num], expire_time);
>> +        if (expire_time > now) {
>> +            timer_mod(s->toy_timer[num], expire_time);
>> +        }
> Should rtc alarm interrupt be injected directly if (expire_time <= now)?
>
Through experiments on the hardware platform, sending an alarm less than
the current time to loongson rtc alarm does not trigger an interrupt.

According to the behavior of the hardware, we do not need to trigger an
interrupt immediately when expire_time <= now

Thanks,
Xianglai Li.

> Regards
> Bibo Mao
>>       }
>>   }
>>     static void rtcmatch_write(LS7ARtcState *s, uint64_t val, int num)
>>   {
>> -    uint64_t expire_ns;
>> +    int64_t expire_ns;
>>         /* it do not support write when toy disabled */
>>       if (rtc_enabled(s)) {
>>           s->rtcmatch[num] = val;
>>           /* calculate expire time */
>>           expire_ns = ticks_to_ns(val) - ticks_to_ns(s->offset_rtc);
>> -        timer_mod_ns(s->rtc_timer[num], expire_ns);
>> +        if (expire_ns > 0) {
>> +            timer_mod_ns(s->rtc_timer[num], expire_ns);
>> +        }
>>       }
>>   }
>>   @@ -185,7 +189,7 @@ static void ls7a_rtc_stop(LS7ARtcState *s)
>>   static void ls7a_toy_start(LS7ARtcState *s)
>>   {
>>       int i;
>> -    uint64_t expire_time, now;
>> +    int64_t expire_time, now;
>>       struct tm tm = {};
>>         now = qemu_clock_get_ms(rtc_clock);
>> @@ -194,19 +198,23 @@ static void ls7a_toy_start(LS7ARtcState *s)
>>       for (i = 0; i < TIMER_NUMS; i++) {
>>           toymatch_val_to_time(s, s->toymatch[i], &tm);
>>           expire_time = now + (qemu_timedate_diff(&tm) - 
>> s->offset_toy) * 1000;
>> -        timer_mod(s->toy_timer[i], expire_time);
>> +        if (expire_time > now) {
>> +            timer_mod(s->toy_timer[i], expire_time);
>> +        }
>>       }
>>   }
>>     static void ls7a_rtc_start(LS7ARtcState *s)
>>   {
>>       int i;
>> -    uint64_t expire_time;
>> +    int64_t expire_time;
>>         /* recalculate expire time and enable timer */
>>       for (i = 0; i < TIMER_NUMS; i++) {
>>           expire_time = ticks_to_ns(s->rtcmatch[i]) - 
>> ticks_to_ns(s->offset_rtc);
>> -        timer_mod_ns(s->rtc_timer[i], expire_time);
>> +        if (expire_time > 0) {
>> +            timer_mod_ns(s->rtc_timer[i], expire_time);
>> +        }
>>       }
>>   }
>>   @@ -370,7 +378,7 @@ static void toy_timer_cb(void *opaque)
>>       LS7ARtcState *s = opaque;
>>         if (toy_enabled(s)) {
>> -        qemu_irq_raise(s->irq);
>> +        qemu_irq_pulse(s->irq);
>>       }
>>   }
>>   @@ -379,7 +387,7 @@ static void rtc_timer_cb(void *opaque)
>>       LS7ARtcState *s = opaque;
>>         if (rtc_enabled(s)) {
>> -        qemu_irq_raise(s->irq);
>> +        qemu_irq_pulse(s->irq);
>>       }
>>   }
>>

Re: [PATCH V1 1/2] hw/rtc: Fixed loongson rtc emulation errors

[Bibo Mao]

On 2025/7/7 下午2:36, lixianglai wrote:
> Hi Bibo Mao:
>>
>>
>> On 2025/6/13 上午9:31, Xianglai Li wrote:
>>> The expire time is sent to the timer only
>>> when the expire Time is greater than 0 or
>>> greater than now. Otherwise, the timer
>>> will trigger interruption continuously.
>>>
>>> Timer interrupts are sent using pulse functions.
>>>
>>> Signed-off-by: Xianglai Li <lixianglai@loongson.cn>
>>> ---
>>> Cc: Bibo Mao <maobibo@loongson.cn>
>>> Cc: Song Gao <gaosong@loongson.cn>
>>> Cc: Jiaxun Yang <jiaxun.yang@flygoat.com>
>>> Cc: Xianglai Li <lixianglai@loongson.cn>
>>>
>>>   hw/loongarch/virt-fdt-build.c | 11 +++++++++--
>>>   hw/rtc/ls7a_rtc.c             | 26 +++++++++++++++++---------
>>>   2 files changed, 26 insertions(+), 11 deletions(-)
>>>
>>> diff --git a/hw/loongarch/virt-fdt-build.c 
>>> b/hw/loongarch/virt-fdt-build.c
>>> index 728ce46699..c613131a07 100644
>>> --- a/hw/loongarch/virt-fdt-build.c
>>> +++ b/hw/loongarch/virt-fdt-build.c
>>> @@ -17,6 +17,11 @@
>>>   #include "system/reset.h"
>>>   #include "target/loongarch/cpu.h"
>>>   +#define FDT_IRQ_FLAGS_EDGE_LO_HI 1
>>> +#define FDT_IRQ_FLAGS_EDGE_HI_LO 2
>>> +#define FDT_IRQ_FLAGS_LEVEL_HI 4
>>> +#define FDT_IRQ_FLAGS_LEVEL_LO 8
>>> +
>>>   static void create_fdt(LoongArchVirtMachineState *lvms)
>>>   {
>>>       MachineState *ms = MACHINE(lvms);
>>> @@ -416,7 +421,8 @@ static void 
>>> fdt_add_uart_node(LoongArchVirtMachineState *lvms,
>>>       if (chosen) {
>>>           qemu_fdt_setprop_string(ms->fdt, "/chosen", "stdout-path", 
>>> nodename);
>>>       }
>>> -    qemu_fdt_setprop_cells(ms->fdt, nodename, "interrupts", irq, 0x4);
>>> +    qemu_fdt_setprop_cells(ms->fdt, nodename, "interrupts", irq,
>>> +                           FDT_IRQ_FLAGS_LEVEL_HI);
>>>       qemu_fdt_setprop_cell(ms->fdt, nodename, "interrupt-parent",
>>>                             *pch_pic_phandle);
>>>       g_free(nodename);
>>> @@ -436,7 +442,8 @@ static void 
>>> fdt_add_rtc_node(LoongArchVirtMachineState *lvms,
>>>                               "loongson,ls7a-rtc");
>>>       qemu_fdt_setprop_sized_cells(ms->fdt, nodename, "reg", 2, base, 
>>> 2, size);
>>>       qemu_fdt_setprop_cells(ms->fdt, nodename, "interrupts",
>>> -                           VIRT_RTC_IRQ - VIRT_GSI_BASE , 0x4);
>>> +                           VIRT_RTC_IRQ - VIRT_GSI_BASE ,
>>> +                           FDT_IRQ_FLAGS_EDGE_LO_HI);
>>>       qemu_fdt_setprop_cell(ms->fdt, nodename, "interrupt-parent",
>>>                             *pch_pic_phandle);
>>>       g_free(nodename);
>>> diff --git a/hw/rtc/ls7a_rtc.c b/hw/rtc/ls7a_rtc.c
>>> index 10097b2db7..7eca75a42a 100644
>>> --- a/hw/rtc/ls7a_rtc.c
>>> +++ b/hw/rtc/ls7a_rtc.c
>>> @@ -145,20 +145,24 @@ static void toymatch_write(LS7ARtcState *s, 
>>> uint64_t val, int num)
>>>           now = qemu_clock_get_ms(rtc_clock);
>>>           toymatch_val_to_time(s, val, &tm);
>>>           expire_time = now + (qemu_timedate_diff(&tm) - 
>>> s->offset_toy) * 1000;
>>> -        timer_mod(s->toy_timer[num], expire_time);
>>> +        if (expire_time > now) {
>>> +            timer_mod(s->toy_timer[num], expire_time);
>>> +        }
>> Should rtc alarm interrupt be injected directly if (expire_time <= now)?
>>
> Through experiments on the hardware platform, sending an alarm less than
> the current time to loongson rtc alarm does not trigger an interrupt.
> 
> According to the behavior of the hardware, we do not need to trigger an
> interrupt immediately when expire_time <= now
Sounds good. yes, the behavior of qemu emulation should be the same with 
real HW.

Regards
Bibo Mao
> 
> Thanks,
> Xianglai Li.
> 
>> Regards
>> Bibo Mao
>>>       }
>>>   }
>>>     static void rtcmatch_write(LS7ARtcState *s, uint64_t val, int num)
>>>   {
>>> -    uint64_t expire_ns;
>>> +    int64_t expire_ns;
>>>         /* it do not support write when toy disabled */
>>>       if (rtc_enabled(s)) {
>>>           s->rtcmatch[num] = val;
>>>           /* calculate expire time */
>>>           expire_ns = ticks_to_ns(val) - ticks_to_ns(s->offset_rtc);
>>> -        timer_mod_ns(s->rtc_timer[num], expire_ns);
>>> +        if (expire_ns > 0) {
>>> +            timer_mod_ns(s->rtc_timer[num], expire_ns);
>>> +        }
>>>       }
>>>   }
>>>   @@ -185,7 +189,7 @@ static void ls7a_rtc_stop(LS7ARtcState *s)
>>>   static void ls7a_toy_start(LS7ARtcState *s)
>>>   {
>>>       int i;
>>> -    uint64_t expire_time, now;
>>> +    int64_t expire_time, now;
>>>       struct tm tm = {};
>>>         now = qemu_clock_get_ms(rtc_clock);
>>> @@ -194,19 +198,23 @@ static void ls7a_toy_start(LS7ARtcState *s)
>>>       for (i = 0; i < TIMER_NUMS; i++) {
>>>           toymatch_val_to_time(s, s->toymatch[i], &tm);
>>>           expire_time = now + (qemu_timedate_diff(&tm) - 
>>> s->offset_toy) * 1000;
>>> -        timer_mod(s->toy_timer[i], expire_time);
>>> +        if (expire_time > now) {
>>> +            timer_mod(s->toy_timer[i], expire_time);
>>> +        }
>>>       }
>>>   }
>>>     static void ls7a_rtc_start(LS7ARtcState *s)
>>>   {
>>>       int i;
>>> -    uint64_t expire_time;
>>> +    int64_t expire_time;
>>>         /* recalculate expire time and enable timer */
>>>       for (i = 0; i < TIMER_NUMS; i++) {
>>>           expire_time = ticks_to_ns(s->rtcmatch[i]) - 
>>> ticks_to_ns(s->offset_rtc);
>>> -        timer_mod_ns(s->rtc_timer[i], expire_time);
>>> +        if (expire_time > 0) {
>>> +            timer_mod_ns(s->rtc_timer[i], expire_time);
>>> +        }
>>>       }
>>>   }
>>>   @@ -370,7 +378,7 @@ static void toy_timer_cb(void *opaque)
>>>       LS7ARtcState *s = opaque;
>>>         if (toy_enabled(s)) {
>>> -        qemu_irq_raise(s->irq);
>>> +        qemu_irq_pulse(s->irq);
>>>       }
>>>   }
>>>   @@ -379,7 +387,7 @@ static void rtc_timer_cb(void *opaque)
>>>       LS7ARtcState *s = opaque;
>>>         if (rtc_enabled(s)) {
>>> -        qemu_irq_raise(s->irq);
>>> +        qemu_irq_pulse(s->irq);
>>>       }
>>>   }
>>>