diff mbox series

[kvmtool,02/21] hw/serial: Use device abstraction for FDT generator function

Message ID 20201210142908.169597-3-andre.przywara@arm.com (mailing list archive)
State New, archived
Headers show
Series Unify I/O port and MMIO trap handling | expand

Commit Message

Andre Przywara Dec. 10, 2020, 2:28 p.m. UTC
At the moment we use the .generate_fdt_node member of the ioport ops
structure to store the function pointer for the FDT node generator
function. ioport__register() will then put a wrapper and this pointer
into the device header.
The serial device is the only device making use of this special ioport
feature, so let's move this over to using the device header directly.

This will allow us to get rid of this .generate_fdt_node member in the
ops and simplify the code.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
---
 hw/serial.c       | 49 +++++++++++++++++++++++++++++++++++++----------
 include/kvm/kvm.h |  2 ++
 2 files changed, 41 insertions(+), 10 deletions(-)

Comments

Alexandru Elisei Feb. 11, 2021, 12:05 p.m. UTC | #1
Hi Andre,

On 12/10/20 2:28 PM, Andre Przywara wrote:
> At the moment we use the .generate_fdt_node member of the ioport ops
> structure to store the function pointer for the FDT node generator
> function. ioport__register() will then put a wrapper and this pointer
> into the device header.
> The serial device is the only device making use of this special ioport
> feature, so let's move this over to using the device header directly.
>
> This will allow us to get rid of this .generate_fdt_node member in the
> ops and simplify the code.
>
> Signed-off-by: Andre Przywara <andre.przywara@arm.com>
> ---
>  hw/serial.c       | 49 +++++++++++++++++++++++++++++++++++++----------
>  include/kvm/kvm.h |  2 ++
>  2 files changed, 41 insertions(+), 10 deletions(-)
>
> diff --git a/hw/serial.c b/hw/serial.c
> index 13c4663e..b0465d99 100644
> --- a/hw/serial.c
> +++ b/hw/serial.c
> @@ -23,6 +23,7 @@
>  #define UART_IIR_TYPE_BITS	0xc0
>  
>  struct serial8250_device {
> +	struct device_header	dev_hdr;
>  	struct mutex		mutex;
>  	u8			id;
>  
> @@ -53,9 +54,20 @@ struct serial8250_device {
>  	.msr			= UART_MSR_DCD | UART_MSR_DSR | UART_MSR_CTS, \
>  	.mcr			= UART_MCR_OUT2,
>  
> +#ifdef CONFIG_HAS_LIBFDT
> +static
> +void serial8250_generate_fdt_node(void *fdt, struct device_header *dev_hdr,
> +				  fdt_irq_fn irq_fn);
> +#else
> +#define serial8250_generate_fdt_node	NULL
> +#endif
>  static struct serial8250_device devices[] = {
>  	/* ttyS0 */
>  	[0]	= {
> +		.dev_hdr = {
> +			.bus_type	= DEVICE_BUS_IOPORT,
> +			.data		= serial8250_generate_fdt_node,
> +		},
>  		.mutex			= MUTEX_INITIALIZER,
>  
>  		.id			= 0,
> @@ -66,6 +78,10 @@ static struct serial8250_device devices[] = {
>  	},
>  	/* ttyS1 */
>  	[1]	= {
> +		.dev_hdr = {
> +			.bus_type	= DEVICE_BUS_IOPORT,
> +			.data		= serial8250_generate_fdt_node,
> +		},
>  		.mutex			= MUTEX_INITIALIZER,
>  
>  		.id			= 1,
> @@ -76,6 +92,10 @@ static struct serial8250_device devices[] = {
>  	},
>  	/* ttyS2 */
>  	[2]	= {
> +		.dev_hdr = {
> +			.bus_type	= DEVICE_BUS_IOPORT,
> +			.data		= serial8250_generate_fdt_node,
> +		},
>  		.mutex			= MUTEX_INITIALIZER,
>  
>  		.id			= 2,
> @@ -86,6 +106,10 @@ static struct serial8250_device devices[] = {
>  	},
>  	/* ttyS3 */
>  	[3]	= {
> +		.dev_hdr = {
> +			.bus_type	= DEVICE_BUS_IOPORT,
> +			.data		= serial8250_generate_fdt_node,
> +		},
>  		.mutex			= MUTEX_INITIALIZER,
>  
>  		.id			= 3,
> @@ -371,13 +395,14 @@ char *fdt_stdout_path = NULL;
>  
>  #define DEVICE_NAME_MAX_LEN 32
>  static
> -void serial8250_generate_fdt_node(struct ioport *ioport, void *fdt,
> -				  void (*generate_irq_prop)(void *fdt,
> -							    u8 irq,
> -							    enum irq_type))
> +void serial8250_generate_fdt_node(void *fdt, struct device_header *dev_hdr,
> +				  fdt_irq_fn irq_fn)
>  {
>  	char dev_name[DEVICE_NAME_MAX_LEN];
> -	struct serial8250_device *dev = ioport->priv;
> +	struct serial8250_device *dev = container_of(dev_hdr,
> +						     struct serial8250_device,
> +						     dev_hdr);
> +
>  	u64 addr = KVM_IOPORT_AREA + dev->iobase;
>  	u64 reg_prop[] = {
>  		cpu_to_fdt64(addr),
> @@ -395,24 +420,26 @@ void serial8250_generate_fdt_node(struct ioport *ioport, void *fdt,
>  	_FDT(fdt_begin_node(fdt, dev_name));
>  	_FDT(fdt_property_string(fdt, "compatible", "ns16550a"));
>  	_FDT(fdt_property(fdt, "reg", reg_prop, sizeof(reg_prop)));
> -	generate_irq_prop(fdt, dev->irq, IRQ_TYPE_LEVEL_HIGH);
> +	irq_fn(fdt, dev->irq, IRQ_TYPE_LEVEL_HIGH);
>  	_FDT(fdt_property_cell(fdt, "clock-frequency", 1843200));
>  	_FDT(fdt_end_node(fdt));
>  }
> -#else
> -#define serial8250_generate_fdt_node	NULL
>  #endif
>  
>  static struct ioport_operations serial8250_ops = {
>  	.io_in			= serial8250_in,
>  	.io_out			= serial8250_out,
> -	.generate_fdt_node	= serial8250_generate_fdt_node,
>  };
>  
> -static int serial8250__device_init(struct kvm *kvm, struct serial8250_device *dev)
> +static int serial8250__device_init(struct kvm *kvm,
> +				   struct serial8250_device *dev)
>  {
>  	int r;
>  
> +	r = device__register(&dev->dev_hdr);
> +	if (r < 0)
> +		return r;
> +
>  	ioport__map_irq(&dev->irq);
>  	r = ioport__register(kvm, dev->iobase, &serial8250_ops, 8, dev);

It's unfortunate that we now create two devices for one serial instance: one here,
and one created by ioport__register(). But I guess that's unavoidable in this
patch, and later patches will remove it.

>  
> @@ -438,6 +465,7 @@ cleanup:
>  		struct serial8250_device *dev = &devices[j];
>  
>  		ioport__unregister(kvm, dev->iobase);
> +		device__unregister(&dev->dev_hdr);
>  	}
>  
>  	return r;
> @@ -455,6 +483,7 @@ int serial8250__exit(struct kvm *kvm)
>  		r = ioport__unregister(kvm, dev->iobase);
>  		if (r < 0)
>  			return r;
> +		device__unregister(&dev->dev_hdr);
>  	}
>  
>  	return 0;
> diff --git a/include/kvm/kvm.h b/include/kvm/kvm.h
> index 53373b08..ee99c28e 100644
> --- a/include/kvm/kvm.h
> +++ b/include/kvm/kvm.h
> @@ -31,6 +31,8 @@
>  	.name = #ext,			\
>  	.code = ext
>  
> +typedef void (*fdt_irq_fn)(void *fdt, u8 irq, enum irq_type);

Shouldn't that last parameter be enum irq_type irq_type? Would you consider moving
the typedef to include/kvm/fdt.h?

Other than the nitpicks above, the patch looks sound to me. I also did a quick
test by running kvm-unit-tests:

Reviewed-by: Alexandru Elisei <alexandru.elisei@arm.com>

Thanks,
Alex
> +
>  enum {
>  	KVM_VMSTATE_RUNNING,
>  	KVM_VMSTATE_PAUSED,
Andre Przywara Feb. 11, 2021, 5:45 p.m. UTC | #2
On Thu, 11 Feb 2021 12:05:35 +0000
Alexandru Elisei <alexandru.elisei@arm.com> wrote:

Hi,

> On 12/10/20 2:28 PM, Andre Przywara wrote:
> > At the moment we use the .generate_fdt_node member of the ioport ops
> > structure to store the function pointer for the FDT node generator
> > function. ioport__register() will then put a wrapper and this pointer
> > into the device header.
> > The serial device is the only device making use of this special ioport
> > feature, so let's move this over to using the device header directly.
> >
> > This will allow us to get rid of this .generate_fdt_node member in the
> > ops and simplify the code.
> >
> > Signed-off-by: Andre Przywara <andre.przywara@arm.com>
> > ---
> >  hw/serial.c       | 49 +++++++++++++++++++++++++++++++++++++----------
> >  include/kvm/kvm.h |  2 ++
> >  2 files changed, 41 insertions(+), 10 deletions(-)
> >
> > diff --git a/hw/serial.c b/hw/serial.c
> > index 13c4663e..b0465d99 100644
> > --- a/hw/serial.c
> > +++ b/hw/serial.c
> > @@ -23,6 +23,7 @@
> >  #define UART_IIR_TYPE_BITS	0xc0
> >  
> >  struct serial8250_device {
> > +	struct device_header	dev_hdr;
> >  	struct mutex		mutex;
> >  	u8			id;
> >  
> > @@ -53,9 +54,20 @@ struct serial8250_device {
> >  	.msr			= UART_MSR_DCD | UART_MSR_DSR | UART_MSR_CTS, \
> >  	.mcr			= UART_MCR_OUT2,
> >  
> > +#ifdef CONFIG_HAS_LIBFDT
> > +static
> > +void serial8250_generate_fdt_node(void *fdt, struct device_header *dev_hdr,
> > +				  fdt_irq_fn irq_fn);
> > +#else
> > +#define serial8250_generate_fdt_node	NULL
> > +#endif
> >  static struct serial8250_device devices[] = {
> >  	/* ttyS0 */
> >  	[0]	= {
> > +		.dev_hdr = {
> > +			.bus_type	= DEVICE_BUS_IOPORT,
> > +			.data		= serial8250_generate_fdt_node,
> > +		},
> >  		.mutex			= MUTEX_INITIALIZER,
> >  
> >  		.id			= 0,
> > @@ -66,6 +78,10 @@ static struct serial8250_device devices[] = {
> >  	},
> >  	/* ttyS1 */
> >  	[1]	= {
> > +		.dev_hdr = {
> > +			.bus_type	= DEVICE_BUS_IOPORT,
> > +			.data		= serial8250_generate_fdt_node,
> > +		},
> >  		.mutex			= MUTEX_INITIALIZER,
> >  
> >  		.id			= 1,
> > @@ -76,6 +92,10 @@ static struct serial8250_device devices[] = {
> >  	},
> >  	/* ttyS2 */
> >  	[2]	= {
> > +		.dev_hdr = {
> > +			.bus_type	= DEVICE_BUS_IOPORT,
> > +			.data		= serial8250_generate_fdt_node,
> > +		},
> >  		.mutex			= MUTEX_INITIALIZER,
> >  
> >  		.id			= 2,
> > @@ -86,6 +106,10 @@ static struct serial8250_device devices[] = {
> >  	},
> >  	/* ttyS3 */
> >  	[3]	= {
> > +		.dev_hdr = {
> > +			.bus_type	= DEVICE_BUS_IOPORT,
> > +			.data		= serial8250_generate_fdt_node,
> > +		},
> >  		.mutex			= MUTEX_INITIALIZER,
> >  
> >  		.id			= 3,
> > @@ -371,13 +395,14 @@ char *fdt_stdout_path = NULL;
> >  
> >  #define DEVICE_NAME_MAX_LEN 32
> >  static
> > -void serial8250_generate_fdt_node(struct ioport *ioport, void *fdt,
> > -				  void (*generate_irq_prop)(void *fdt,
> > -							    u8 irq,
> > -							    enum irq_type))
> > +void serial8250_generate_fdt_node(void *fdt, struct device_header *dev_hdr,
> > +				  fdt_irq_fn irq_fn)
> >  {
> >  	char dev_name[DEVICE_NAME_MAX_LEN];
> > -	struct serial8250_device *dev = ioport->priv;
> > +	struct serial8250_device *dev = container_of(dev_hdr,
> > +						     struct serial8250_device,
> > +						     dev_hdr);
> > +
> >  	u64 addr = KVM_IOPORT_AREA + dev->iobase;
> >  	u64 reg_prop[] = {
> >  		cpu_to_fdt64(addr),
> > @@ -395,24 +420,26 @@ void serial8250_generate_fdt_node(struct ioport *ioport, void *fdt,
> >  	_FDT(fdt_begin_node(fdt, dev_name));
> >  	_FDT(fdt_property_string(fdt, "compatible", "ns16550a"));
> >  	_FDT(fdt_property(fdt, "reg", reg_prop, sizeof(reg_prop)));
> > -	generate_irq_prop(fdt, dev->irq, IRQ_TYPE_LEVEL_HIGH);
> > +	irq_fn(fdt, dev->irq, IRQ_TYPE_LEVEL_HIGH);
> >  	_FDT(fdt_property_cell(fdt, "clock-frequency", 1843200));
> >  	_FDT(fdt_end_node(fdt));
> >  }
> > -#else
> > -#define serial8250_generate_fdt_node	NULL
> >  #endif
> >  
> >  static struct ioport_operations serial8250_ops = {
> >  	.io_in			= serial8250_in,
> >  	.io_out			= serial8250_out,
> > -	.generate_fdt_node	= serial8250_generate_fdt_node,
> >  };
> >  
> > -static int serial8250__device_init(struct kvm *kvm, struct serial8250_device *dev)
> > +static int serial8250__device_init(struct kvm *kvm,
> > +				   struct serial8250_device *dev)
> >  {
> >  	int r;
> >  
> > +	r = device__register(&dev->dev_hdr);
> > +	if (r < 0)
> > +		return r;
> > +
> >  	ioport__map_irq(&dev->irq);
> >  	r = ioport__register(kvm, dev->iobase, &serial8250_ops, 8, dev);  
> 
> It's unfortunate that we now create two devices for one serial instance: one here,
> and one created by ioport__register(). But I guess that's unavoidable in this
> patch, and later patches will remove it.

Well, we do this already, wherever we register multiple I/O ports per
device, RTC and i8042 are an example (because we register one device
per I/O port). This really isn't a particular problem, it's just ugly,
so just get's a tiny bit more uglier for a few patches that
hopefully nobody will actually use (in anger).

> 
> >  
> > @@ -438,6 +465,7 @@ cleanup:
> >  		struct serial8250_device *dev = &devices[j];
> >  
> >  		ioport__unregister(kvm, dev->iobase);
> > +		device__unregister(&dev->dev_hdr);
> >  	}
> >  
> >  	return r;
> > @@ -455,6 +483,7 @@ int serial8250__exit(struct kvm *kvm)
> >  		r = ioport__unregister(kvm, dev->iobase);
> >  		if (r < 0)
> >  			return r;
> > +		device__unregister(&dev->dev_hdr);
> >  	}
> >  
> >  	return 0;
> > diff --git a/include/kvm/kvm.h b/include/kvm/kvm.h
> > index 53373b08..ee99c28e 100644
> > --- a/include/kvm/kvm.h
> > +++ b/include/kvm/kvm.h
> > @@ -31,6 +31,8 @@
> >  	.name = #ext,			\
> >  	.code = ext
> >  
> > +typedef void (*fdt_irq_fn)(void *fdt, u8 irq, enum irq_type);  
> 
> Shouldn't that last parameter be enum irq_type irq_type? Would you consider moving
> the typedef to include/kvm/fdt.h?

I think where I came from was that typedef's don't need parameter names,
just the type. But just having (void *, u8, enum irq_type) is really
hard to understand, so I added parameter names where this helps. "enum
irq_type irq_type" looks redundant, but I can certainly add this for
consistency.

> Other than the nitpicks above, the patch looks sound to me. I also did a quick
> test by running kvm-unit-tests:
> 
> Reviewed-by: Alexandru Elisei <alexandru.elisei@arm.com>

Thanks!

Andre

> 
> Thanks,
> Alex
> > +
> >  enum {
> >  	KVM_VMSTATE_RUNNING,
> >  	KVM_VMSTATE_PAUSED,
diff mbox series

Patch

diff --git a/hw/serial.c b/hw/serial.c
index 13c4663e..b0465d99 100644
--- a/hw/serial.c
+++ b/hw/serial.c
@@ -23,6 +23,7 @@ 
 #define UART_IIR_TYPE_BITS	0xc0
 
 struct serial8250_device {
+	struct device_header	dev_hdr;
 	struct mutex		mutex;
 	u8			id;
 
@@ -53,9 +54,20 @@  struct serial8250_device {
 	.msr			= UART_MSR_DCD | UART_MSR_DSR | UART_MSR_CTS, \
 	.mcr			= UART_MCR_OUT2,
 
+#ifdef CONFIG_HAS_LIBFDT
+static
+void serial8250_generate_fdt_node(void *fdt, struct device_header *dev_hdr,
+				  fdt_irq_fn irq_fn);
+#else
+#define serial8250_generate_fdt_node	NULL
+#endif
 static struct serial8250_device devices[] = {
 	/* ttyS0 */
 	[0]	= {
+		.dev_hdr = {
+			.bus_type	= DEVICE_BUS_IOPORT,
+			.data		= serial8250_generate_fdt_node,
+		},
 		.mutex			= MUTEX_INITIALIZER,
 
 		.id			= 0,
@@ -66,6 +78,10 @@  static struct serial8250_device devices[] = {
 	},
 	/* ttyS1 */
 	[1]	= {
+		.dev_hdr = {
+			.bus_type	= DEVICE_BUS_IOPORT,
+			.data		= serial8250_generate_fdt_node,
+		},
 		.mutex			= MUTEX_INITIALIZER,
 
 		.id			= 1,
@@ -76,6 +92,10 @@  static struct serial8250_device devices[] = {
 	},
 	/* ttyS2 */
 	[2]	= {
+		.dev_hdr = {
+			.bus_type	= DEVICE_BUS_IOPORT,
+			.data		= serial8250_generate_fdt_node,
+		},
 		.mutex			= MUTEX_INITIALIZER,
 
 		.id			= 2,
@@ -86,6 +106,10 @@  static struct serial8250_device devices[] = {
 	},
 	/* ttyS3 */
 	[3]	= {
+		.dev_hdr = {
+			.bus_type	= DEVICE_BUS_IOPORT,
+			.data		= serial8250_generate_fdt_node,
+		},
 		.mutex			= MUTEX_INITIALIZER,
 
 		.id			= 3,
@@ -371,13 +395,14 @@  char *fdt_stdout_path = NULL;
 
 #define DEVICE_NAME_MAX_LEN 32
 static
-void serial8250_generate_fdt_node(struct ioport *ioport, void *fdt,
-				  void (*generate_irq_prop)(void *fdt,
-							    u8 irq,
-							    enum irq_type))
+void serial8250_generate_fdt_node(void *fdt, struct device_header *dev_hdr,
+				  fdt_irq_fn irq_fn)
 {
 	char dev_name[DEVICE_NAME_MAX_LEN];
-	struct serial8250_device *dev = ioport->priv;
+	struct serial8250_device *dev = container_of(dev_hdr,
+						     struct serial8250_device,
+						     dev_hdr);
+
 	u64 addr = KVM_IOPORT_AREA + dev->iobase;
 	u64 reg_prop[] = {
 		cpu_to_fdt64(addr),
@@ -395,24 +420,26 @@  void serial8250_generate_fdt_node(struct ioport *ioport, void *fdt,
 	_FDT(fdt_begin_node(fdt, dev_name));
 	_FDT(fdt_property_string(fdt, "compatible", "ns16550a"));
 	_FDT(fdt_property(fdt, "reg", reg_prop, sizeof(reg_prop)));
-	generate_irq_prop(fdt, dev->irq, IRQ_TYPE_LEVEL_HIGH);
+	irq_fn(fdt, dev->irq, IRQ_TYPE_LEVEL_HIGH);
 	_FDT(fdt_property_cell(fdt, "clock-frequency", 1843200));
 	_FDT(fdt_end_node(fdt));
 }
-#else
-#define serial8250_generate_fdt_node	NULL
 #endif
 
 static struct ioport_operations serial8250_ops = {
 	.io_in			= serial8250_in,
 	.io_out			= serial8250_out,
-	.generate_fdt_node	= serial8250_generate_fdt_node,
 };
 
-static int serial8250__device_init(struct kvm *kvm, struct serial8250_device *dev)
+static int serial8250__device_init(struct kvm *kvm,
+				   struct serial8250_device *dev)
 {
 	int r;
 
+	r = device__register(&dev->dev_hdr);
+	if (r < 0)
+		return r;
+
 	ioport__map_irq(&dev->irq);
 	r = ioport__register(kvm, dev->iobase, &serial8250_ops, 8, dev);
 
@@ -438,6 +465,7 @@  cleanup:
 		struct serial8250_device *dev = &devices[j];
 
 		ioport__unregister(kvm, dev->iobase);
+		device__unregister(&dev->dev_hdr);
 	}
 
 	return r;
@@ -455,6 +483,7 @@  int serial8250__exit(struct kvm *kvm)
 		r = ioport__unregister(kvm, dev->iobase);
 		if (r < 0)
 			return r;
+		device__unregister(&dev->dev_hdr);
 	}
 
 	return 0;
diff --git a/include/kvm/kvm.h b/include/kvm/kvm.h
index 53373b08..ee99c28e 100644
--- a/include/kvm/kvm.h
+++ b/include/kvm/kvm.h
@@ -31,6 +31,8 @@ 
 	.name = #ext,			\
 	.code = ext
 
+typedef void (*fdt_irq_fn)(void *fdt, u8 irq, enum irq_type);
+
 enum {
 	KVM_VMSTATE_RUNNING,
 	KVM_VMSTATE_PAUSED,