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* [PATCH v2 1/2] hw/ppc: e500: Use a macro for the platform clock frequency
@ 2021-02-03 14:24 Bin Meng
  2021-02-03 14:24 ` [PATCH v2 2/2] hw/ppc: e500: Fill in correct <clock-frequency> for the serial nodes Bin Meng
  2021-02-04  2:59 ` [PATCH v2 1/2] hw/ppc: e500: Use a macro for the platform clock frequency David Gibson
  0 siblings, 2 replies; 6+ messages in thread
From: Bin Meng @ 2021-02-03 14:24 UTC (permalink / raw)
  To: David Gibson, Greg Kurz
  Cc: Bin Meng, qemu-ppc, qemu-devel, Philippe Mathieu-Daudé

From: Bin Meng <bin.meng@windriver.com>

At present the platform clock frequency is using a magic number.
Convert it to a macro and use it everywhere.

Signed-off-by: Bin Meng <bin.meng@windriver.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>

---

Changes in v2:
- Rename the macro per Philippe's comments

 hw/ppc/e500.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/hw/ppc/e500.c b/hw/ppc/e500.c
index c64b5d0..c795276 100644
--- a/hw/ppc/e500.c
+++ b/hw/ppc/e500.c
@@ -74,6 +74,8 @@
 #define MPC8544_I2C_IRQ            43
 #define RTC_REGS_OFFSET            0x68
 
+#define PLATFORM_CLK_FREQ_HZ       (400 * 1000 * 1000)
+
 struct boot_info
 {
     uint32_t dt_base;
@@ -320,8 +322,8 @@ static int ppce500_load_device_tree(PPCE500MachineState *pms,
     int fdt_size;
     void *fdt;
     uint8_t hypercall[16];
-    uint32_t clock_freq = 400000000;
-    uint32_t tb_freq = 400000000;
+    uint32_t clock_freq = PLATFORM_CLK_FREQ_HZ;
+    uint32_t tb_freq = PLATFORM_CLK_FREQ_HZ;
     int i;
     char compatible_sb[] = "fsl,mpc8544-immr\0simple-bus";
     char *soc;
@@ -890,7 +892,7 @@ void ppce500_init(MachineState *machine)
         env->spr_cb[SPR_BOOKE_PIR].default_value = cs->cpu_index = i;
         env->mpic_iack = pmc->ccsrbar_base + MPC8544_MPIC_REGS_OFFSET + 0xa0;
 
-        ppc_booke_timers_init(cpu, 400000000, PPC_TIMER_E500);
+        ppc_booke_timers_init(cpu, PLATFORM_CLK_FREQ_HZ, PPC_TIMER_E500);
 
         /* Register reset handler */
         if (!i) {
-- 
2.7.4



^ permalink raw reply related	[flat|nested] 6+ messages in thread

* [PATCH v2 2/2] hw/ppc: e500: Fill in correct <clock-frequency> for the serial nodes
  2021-02-03 14:24 [PATCH v2 1/2] hw/ppc: e500: Use a macro for the platform clock frequency Bin Meng
@ 2021-02-03 14:24 ` Bin Meng
  2021-02-04  2:59   ` David Gibson
  2021-02-04  2:59 ` [PATCH v2 1/2] hw/ppc: e500: Use a macro for the platform clock frequency David Gibson
  1 sibling, 1 reply; 6+ messages in thread
From: Bin Meng @ 2021-02-03 14:24 UTC (permalink / raw)
  To: David Gibson, Greg Kurz
  Cc: Bin Meng, qemu-ppc, qemu-devel, Philippe Mathieu-Daudé

From: Bin Meng <bin.meng@windriver.com>

At present the <clock-frequency> property of the serial node is
populated with value zero. U-Boot's ns16550 driver is not happy
about this, so let's fill in a meaningful value.

Signed-off-by: Bin Meng <bin.meng@windriver.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>

---

(no changes since v1)

 hw/ppc/e500.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/hw/ppc/e500.c b/hw/ppc/e500.c
index c795276..01517a6 100644
--- a/hw/ppc/e500.c
+++ b/hw/ppc/e500.c
@@ -126,7 +126,7 @@ static void dt_serial_create(void *fdt, unsigned long long offset,
     qemu_fdt_setprop_string(fdt, ser, "compatible", "ns16550");
     qemu_fdt_setprop_cells(fdt, ser, "reg", offset, 0x100);
     qemu_fdt_setprop_cell(fdt, ser, "cell-index", idx);
-    qemu_fdt_setprop_cell(fdt, ser, "clock-frequency", 0);
+    qemu_fdt_setprop_cell(fdt, ser, "clock-frequency", PLATFORM_CLK_FREQ_HZ);
     qemu_fdt_setprop_cells(fdt, ser, "interrupts", 42, 2);
     qemu_fdt_setprop_phandle(fdt, ser, "interrupt-parent", mpic);
     qemu_fdt_setprop_string(fdt, "/aliases", alias, ser);
-- 
2.7.4



^ permalink raw reply related	[flat|nested] 6+ messages in thread

* Re: [PATCH v2 1/2] hw/ppc: e500: Use a macro for the platform clock frequency
  2021-02-03 14:24 [PATCH v2 1/2] hw/ppc: e500: Use a macro for the platform clock frequency Bin Meng
  2021-02-03 14:24 ` [PATCH v2 2/2] hw/ppc: e500: Fill in correct <clock-frequency> for the serial nodes Bin Meng
@ 2021-02-04  2:59 ` David Gibson
  1 sibling, 0 replies; 6+ messages in thread
From: David Gibson @ 2021-02-04  2:59 UTC (permalink / raw)
  To: Bin Meng
  Cc: Bin Meng, Philippe Mathieu-Daudé, qemu-ppc, Greg Kurz,
	qemu-devel

[-- Attachment #1: Type: text/plain, Size: 1964 bytes --]

On Wed, Feb 03, 2021 at 10:24:47PM +0800, Bin Meng wrote:
> From: Bin Meng <bin.meng@windriver.com>
> 
> At present the platform clock frequency is using a magic number.
> Convert it to a macro and use it everywhere.
> 
> Signed-off-by: Bin Meng <bin.meng@windriver.com>
> Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>

Applied to ppc-for-6.0, thanks.

> 
> ---
> 
> Changes in v2:
> - Rename the macro per Philippe's comments
> 
>  hw/ppc/e500.c | 8 +++++---
>  1 file changed, 5 insertions(+), 3 deletions(-)
> 
> diff --git a/hw/ppc/e500.c b/hw/ppc/e500.c
> index c64b5d0..c795276 100644
> --- a/hw/ppc/e500.c
> +++ b/hw/ppc/e500.c
> @@ -74,6 +74,8 @@
>  #define MPC8544_I2C_IRQ            43
>  #define RTC_REGS_OFFSET            0x68
>  
> +#define PLATFORM_CLK_FREQ_HZ       (400 * 1000 * 1000)
> +
>  struct boot_info
>  {
>      uint32_t dt_base;
> @@ -320,8 +322,8 @@ static int ppce500_load_device_tree(PPCE500MachineState *pms,
>      int fdt_size;
>      void *fdt;
>      uint8_t hypercall[16];
> -    uint32_t clock_freq = 400000000;
> -    uint32_t tb_freq = 400000000;
> +    uint32_t clock_freq = PLATFORM_CLK_FREQ_HZ;
> +    uint32_t tb_freq = PLATFORM_CLK_FREQ_HZ;
>      int i;
>      char compatible_sb[] = "fsl,mpc8544-immr\0simple-bus";
>      char *soc;
> @@ -890,7 +892,7 @@ void ppce500_init(MachineState *machine)
>          env->spr_cb[SPR_BOOKE_PIR].default_value = cs->cpu_index = i;
>          env->mpic_iack = pmc->ccsrbar_base + MPC8544_MPIC_REGS_OFFSET + 0xa0;
>  
> -        ppc_booke_timers_init(cpu, 400000000, PPC_TIMER_E500);
> +        ppc_booke_timers_init(cpu, PLATFORM_CLK_FREQ_HZ, PPC_TIMER_E500);
>  
>          /* Register reset handler */
>          if (!i) {

-- 
David Gibson			| I'll have my music baroque, and my code
david AT gibson.dropbear.id.au	| minimalist, thank you.  NOT _the_ _other_
				| _way_ _around_!
http://www.ozlabs.org/~dgibson

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^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: [PATCH v2 2/2] hw/ppc: e500: Fill in correct <clock-frequency> for the serial nodes
  2021-02-03 14:24 ` [PATCH v2 2/2] hw/ppc: e500: Fill in correct <clock-frequency> for the serial nodes Bin Meng
@ 2021-02-04  2:59   ` David Gibson
  2021-02-04  5:05     ` Bin Meng
  0 siblings, 1 reply; 6+ messages in thread
From: David Gibson @ 2021-02-04  2:59 UTC (permalink / raw)
  To: Bin Meng
  Cc: Bin Meng, Philippe Mathieu-Daudé, qemu-ppc, Greg Kurz,
	qemu-devel

[-- Attachment #1: Type: text/plain, Size: 1641 bytes --]

On Wed, Feb 03, 2021 at 10:24:48PM +0800, Bin Meng wrote:
> From: Bin Meng <bin.meng@windriver.com>
> 
> At present the <clock-frequency> property of the serial node is
> populated with value zero. U-Boot's ns16550 driver is not happy
> about this, so let's fill in a meaningful value.

Are you sure this is correct - that is that the serial clock is really
the same as the overall system clock?  Quite often there's some kind
of divider in between.

> 
> Signed-off-by: Bin Meng <bin.meng@windriver.com>
> Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
> 
> ---
> 
> (no changes since v1)
> 
>  hw/ppc/e500.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/hw/ppc/e500.c b/hw/ppc/e500.c
> index c795276..01517a6 100644
> --- a/hw/ppc/e500.c
> +++ b/hw/ppc/e500.c
> @@ -126,7 +126,7 @@ static void dt_serial_create(void *fdt, unsigned long long offset,
>      qemu_fdt_setprop_string(fdt, ser, "compatible", "ns16550");
>      qemu_fdt_setprop_cells(fdt, ser, "reg", offset, 0x100);
>      qemu_fdt_setprop_cell(fdt, ser, "cell-index", idx);
> -    qemu_fdt_setprop_cell(fdt, ser, "clock-frequency", 0);
> +    qemu_fdt_setprop_cell(fdt, ser, "clock-frequency", PLATFORM_CLK_FREQ_HZ);
>      qemu_fdt_setprop_cells(fdt, ser, "interrupts", 42, 2);
>      qemu_fdt_setprop_phandle(fdt, ser, "interrupt-parent", mpic);
>      qemu_fdt_setprop_string(fdt, "/aliases", alias, ser);

-- 
David Gibson			| I'll have my music baroque, and my code
david AT gibson.dropbear.id.au	| minimalist, thank you.  NOT _the_ _other_
				| _way_ _around_!
http://www.ozlabs.org/~dgibson

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^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: [PATCH v2 2/2] hw/ppc: e500: Fill in correct <clock-frequency> for the serial nodes
  2021-02-04  2:59   ` David Gibson
@ 2021-02-04  5:05     ` Bin Meng
  2021-02-04 23:51       ` David Gibson
  0 siblings, 1 reply; 6+ messages in thread
From: Bin Meng @ 2021-02-04  5:05 UTC (permalink / raw)
  To: David Gibson
  Cc: Bin Meng, Philippe Mathieu-Daudé, qemu-ppc, Greg Kurz,
	qemu-devel@nongnu.org Developers

On Thu, Feb 4, 2021 at 12:58 PM David Gibson
<david@gibson.dropbear.id.au> wrote:
>
> On Wed, Feb 03, 2021 at 10:24:48PM +0800, Bin Meng wrote:
> > From: Bin Meng <bin.meng@windriver.com>
> >
> > At present the <clock-frequency> property of the serial node is
> > populated with value zero. U-Boot's ns16550 driver is not happy
> > about this, so let's fill in a meaningful value.
>
> Are you sure this is correct - that is that the serial clock is really
> the same as the overall system clock?  Quite often there's some kind
> of divider in between.
>

Yes, see the U-Boot codes include/configs/qemu-ppce500.h

#define CONFIG_SYS_NS16550_CLK          (get_bus_freq(0))

get_bus_freq(0) eventually returns the platform clock frequency which is 400MHz.

But the value doesn't matter anyway for QEMU. We don't emulate any
baud rate specific thing for a serial port. We only need a sane value
that is non-zero.

Regards,
Bin


^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: [PATCH v2 2/2] hw/ppc: e500: Fill in correct <clock-frequency> for the serial nodes
  2021-02-04  5:05     ` Bin Meng
@ 2021-02-04 23:51       ` David Gibson
  0 siblings, 0 replies; 6+ messages in thread
From: David Gibson @ 2021-02-04 23:51 UTC (permalink / raw)
  To: Bin Meng
  Cc: Bin Meng, Philippe Mathieu-Daudé, qemu-ppc, Greg Kurz,
	qemu-devel@nongnu.org Developers

[-- Attachment #1: Type: text/plain, Size: 1276 bytes --]

On Thu, Feb 04, 2021 at 01:05:19PM +0800, Bin Meng wrote:
> On Thu, Feb 4, 2021 at 12:58 PM David Gibson
> <david@gibson.dropbear.id.au> wrote:
> >
> > On Wed, Feb 03, 2021 at 10:24:48PM +0800, Bin Meng wrote:
> > > From: Bin Meng <bin.meng@windriver.com>
> > >
> > > At present the <clock-frequency> property of the serial node is
> > > populated with value zero. U-Boot's ns16550 driver is not happy
> > > about this, so let's fill in a meaningful value.
> >
> > Are you sure this is correct - that is that the serial clock is really
> > the same as the overall system clock?  Quite often there's some kind
> > of divider in between.
> >
> 
> Yes, see the U-Boot codes include/configs/qemu-ppce500.h
> 
> #define CONFIG_SYS_NS16550_CLK          (get_bus_freq(0))
> 
> get_bus_freq(0) eventually returns the platform clock frequency which is 400MHz.
> 
> But the value doesn't matter anyway for QEMU. We don't emulate any
> baud rate specific thing for a serial port. We only need a sane value
> that is non-zero.

Understood.  Applied to ppc-for-6.0.

-- 
David Gibson			| I'll have my music baroque, and my code
david AT gibson.dropbear.id.au	| minimalist, thank you.  NOT _the_ _other_
				| _way_ _around_!
http://www.ozlabs.org/~dgibson

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^ permalink raw reply	[flat|nested] 6+ messages in thread

end of thread, other threads:[~2021-02-05  0:02 UTC | newest]

Thread overview: 6+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2021-02-03 14:24 [PATCH v2 1/2] hw/ppc: e500: Use a macro for the platform clock frequency Bin Meng
2021-02-03 14:24 ` [PATCH v2 2/2] hw/ppc: e500: Fill in correct <clock-frequency> for the serial nodes Bin Meng
2021-02-04  2:59   ` David Gibson
2021-02-04  5:05     ` Bin Meng
2021-02-04 23:51       ` David Gibson
2021-02-04  2:59 ` [PATCH v2 1/2] hw/ppc: e500: Use a macro for the platform clock frequency David Gibson

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