[PATCH v2 1/3] ACPI: Allow PCI to be disabled for reboot

[PATCH v2 1/3] ACPI: Allow PCI to be disabled for reboot

[Sinan Kaya]

Make PCI reboot conditional on PCI support being present on the kernel
configuration.

Signed-off-by: Sinan Kaya <okaya@kernel.org>
---
 drivers/acpi/reboot.c | 12 +++++++++---
 1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/drivers/acpi/reboot.c b/drivers/acpi/reboot.c
index 6fa9c2a4cfe9..9aa367f098a6 100644
--- a/drivers/acpi/reboot.c
+++ b/drivers/acpi/reboot.c
@@ -7,8 +7,6 @@
 void acpi_reboot(void)
 {
 	struct acpi_generic_address *rr;
-	struct pci_bus *bus0;
-	unsigned int devfn;
 	u8 reset_value;
 
 	if (acpi_disabled)
@@ -33,6 +31,11 @@ void acpi_reboot(void)
 	 * on a device on bus 0. */
 	switch (rr->space_id) {
 	case ACPI_ADR_SPACE_PCI_CONFIG:
+	{
+#ifdef CONFIG_PCI
+		unsigned int devfn;
+		struct pci_bus *bus0;
+
 		/* The reset register can only live on bus 0. */
 		bus0 = pci_find_bus(0, 0);
 		if (!bus0)
@@ -45,7 +48,10 @@ void acpi_reboot(void)
 		pci_bus_write_config_byte(bus0, devfn,
 				(rr->address & 0xffff), reset_value);
 		break;
-
+#else
+		return;
+#endif
+	}
 	case ACPI_ADR_SPACE_SYSTEM_MEMORY:
 	case ACPI_ADR_SPACE_SYSTEM_IO:
 		printk(KERN_DEBUG "ACPI MEMORY or I/O RESET_REG.\n");
-- 
2.19.0

[PATCH v2 2/3] ACPI / OSL: Allow PCI to be disabled

[Sinan Kaya]

Getting ready to allow PCI to be disabled with ACPI enabled. Stub
out calls that depend on PCI.

Signed-off-by: Sinan Kaya <okaya@kernel.org>
---
 drivers/acpi/osl.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c
index b48874b8e1ea..0d3ed659cfe8 100644
--- a/drivers/acpi/osl.c
+++ b/drivers/acpi/osl.c
@@ -773,6 +773,7 @@ acpi_status
 acpi_os_read_pci_configuration(struct acpi_pci_id * pci_id, u32 reg,
 			       u64 *value, u32 width)
 {
+#ifdef CONFIG_PCI
 	int result, size;
 	u32 value32;
 
@@ -799,12 +800,16 @@ acpi_os_read_pci_configuration(struct acpi_pci_id * pci_id, u32 reg,
 	*value = value32;
 
 	return (result ? AE_ERROR : AE_OK);
+#else
+	return AE_SUPPORT;
+#endif
 }
 
 acpi_status
 acpi_os_write_pci_configuration(struct acpi_pci_id * pci_id, u32 reg,
 				u64 value, u32 width)
 {
+#ifdef CONFIG_PCI
 	int result, size;
 
 	switch (width) {
@@ -826,6 +831,9 @@ acpi_os_write_pci_configuration(struct acpi_pci_id * pci_id, u32 reg,
 				reg, size, value);
 
 	return (result ? AE_ERROR : AE_OK);
+#else
+	return AE_SUPPORT;
+#endif
 }
 
 static void acpi_os_execute_deferred(struct work_struct *work)
-- 
2.19.0

[PATCH v2 3/3] PCI/ACPI: allow ACPI to be built without PCI support

[Sinan Kaya]

We are compiling PCI code today for systems with ACPI and no PCI
device present. Remove the useless code and reduce the tight
dependency.

Signed-off-by: Sinan Kaya <okaya@kernel.org>
---
 arch/x86/include/asm/pci_x86.h | 7 +++++++
 drivers/acpi/Kconfig           | 1 -
 drivers/acpi/Makefile          | 2 +-
 drivers/acpi/internal.h        | 5 +++++
 drivers/pci/Makefile           | 2 +-
 include/acpi/acpi_drivers.h    | 7 +++++++
 include/linux/acpi.h           | 7 +++++++
 include/linux/pci.h            | 4 ++++
 8 files changed, 32 insertions(+), 3 deletions(-)

diff --git a/arch/x86/include/asm/pci_x86.h b/arch/x86/include/asm/pci_x86.h
index 959d618dbb17..73bb404f4d2a 100644
--- a/arch/x86/include/asm/pci_x86.h
+++ b/arch/x86/include/asm/pci_x86.h
@@ -121,7 +121,14 @@ extern void __init dmi_check_pciprobe(void);
 extern void __init dmi_check_skip_isa_align(void);
 
 /* some common used subsys_initcalls */
+#ifdef CONFIG_PCI
 extern int __init pci_acpi_init(void);
+#else
+static inline int  __init pci_acpi_init(void)
+{
+	return -EINVAL;
+}
+#endif
 extern void __init pcibios_irq_init(void);
 extern int __init pcibios_init(void);
 extern int pci_legacy_init(void);
diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig
index 7cea769c37df..a0abcb3bd673 100644
--- a/drivers/acpi/Kconfig
+++ b/drivers/acpi/Kconfig
@@ -9,7 +9,6 @@ config ARCH_SUPPORTS_ACPI
 menuconfig ACPI
 	bool "ACPI (Advanced Configuration and Power Interface) Support"
 	depends on ARCH_SUPPORTS_ACPI
-	depends on PCI
 	select PNP
 	default y if X86
 	help
diff --git a/drivers/acpi/Makefile b/drivers/acpi/Makefile
index edc039313cd6..7c6afc111d76 100644
--- a/drivers/acpi/Makefile
+++ b/drivers/acpi/Makefile
@@ -39,7 +39,7 @@ acpi-y				+= processor_core.o
 acpi-$(CONFIG_ARCH_MIGHT_HAVE_ACPI_PDC) += processor_pdc.o
 acpi-y				+= ec.o
 acpi-$(CONFIG_ACPI_DOCK)	+= dock.o
-acpi-y				+= pci_root.o pci_link.o pci_irq.o
+acpi-$(CONFIG_PCI)		+= pci_root.o pci_link.o pci_irq.o
 obj-$(CONFIG_ACPI_MCFG)		+= pci_mcfg.o
 acpi-y				+= acpi_lpss.o acpi_apd.o
 acpi-y				+= acpi_platform.o
diff --git a/drivers/acpi/internal.h b/drivers/acpi/internal.h
index 530a3f675490..b7060dae2789 100644
--- a/drivers/acpi/internal.h
+++ b/drivers/acpi/internal.h
@@ -25,8 +25,13 @@ int acpi_osi_init(void);
 acpi_status acpi_os_initialize1(void);
 void init_acpi_device_notify(void);
 int acpi_scan_init(void);
+#ifdef CONFIG_PCI
 void acpi_pci_root_init(void);
 void acpi_pci_link_init(void);
+#else
+static inline void acpi_pci_root_init(void) {}
+static inline void acpi_pci_link_init(void) {}
+#endif
 void acpi_processor_init(void);
 void acpi_platform_init(void);
 void acpi_pnp_init(void);
diff --git a/drivers/pci/Makefile b/drivers/pci/Makefile
index f2bda77a2df1..657d642fcc67 100644
--- a/drivers/pci/Makefile
+++ b/drivers/pci/Makefile
@@ -11,6 +11,7 @@ ifdef CONFIG_PCI
 obj-$(CONFIG_PROC_FS)		+= proc.o
 obj-$(CONFIG_SYSFS)		+= slot.o
 obj-$(CONFIG_OF)		+= of.o
+obj-$(CONFIG_ACPI)		+= pci-acpi.o
 endif
 
 obj-$(CONFIG_PCI_QUIRKS)	+= quirks.o
@@ -20,7 +21,6 @@ obj-$(CONFIG_PCI_MSI)		+= msi.o
 obj-$(CONFIG_PCI_ATS)		+= ats.o
 obj-$(CONFIG_PCI_IOV)		+= iov.o
 obj-$(CONFIG_PCI_BRIDGE_EMUL)	+= pci-bridge-emul.o
-obj-$(CONFIG_ACPI)		+= pci-acpi.o
 obj-$(CONFIG_PCI_LABEL)		+= pci-label.o
 obj-$(CONFIG_X86_INTEL_MID)	+= pci-mid.o
 obj-$(CONFIG_PCI_SYSCALL)	+= syscall.o
diff --git a/include/acpi/acpi_drivers.h b/include/acpi/acpi_drivers.h
index 14499757338f..9771373dd55e 100644
--- a/include/acpi/acpi_drivers.h
+++ b/include/acpi/acpi_drivers.h
@@ -88,7 +88,14 @@ int acpi_pci_link_free_irq(acpi_handle handle);
 
 struct pci_bus;
 
+#ifdef CONFIG_PCI
 struct pci_dev *acpi_get_pci_dev(acpi_handle);
+#else
+static inline struct pci_dev *acpi_get_pci_dev(acpi_handle hndl)
+{
+	return NULL;
+}
+#endif
 
 /* Arch-defined function to add a bus to the system */
 
diff --git a/include/linux/acpi.h b/include/linux/acpi.h
index ed80f147bd50..eb1fdf4c196a 100644
--- a/include/linux/acpi.h
+++ b/include/linux/acpi.h
@@ -340,7 +340,14 @@ struct pci_dev;
 int acpi_pci_irq_enable (struct pci_dev *dev);
 void acpi_penalize_isa_irq(int irq, int active);
 bool acpi_isa_irq_available(int irq);
+#ifdef CONFIG_PCI
 void acpi_penalize_sci_irq(int irq, int trigger, int polarity);
+#else
+static inline void acpi_penalize_sci_irq(int irq, int trigger,
+					int polarity)
+{
+}
+#endif
 void acpi_pci_irq_disable (struct pci_dev *dev);
 
 extern int ec_read(u8 addr, u8 *val);
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 11c71c4ecf75..51a5a5217667 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -1960,7 +1960,11 @@ int pcibios_set_pcie_reset_state(struct pci_dev *dev,
 				 enum pcie_reset_state state);
 int pcibios_add_device(struct pci_dev *dev);
 void pcibios_release_device(struct pci_dev *dev);
+#ifdef CONFIG_PCI
 void pcibios_penalize_isa_irq(int irq, int active);
+#else
+static inline void pcibios_penalize_isa_irq(int irq, int active) {}
+#endif
 int pcibios_alloc_irq(struct pci_dev *dev);
 void pcibios_free_irq(struct pci_dev *dev);
 resource_size_t pcibios_default_alignment(void);
-- 
2.19.0

Re: [PATCH v2 3/3] PCI/ACPI: allow ACPI to be built without PCI support

[Andy Shevchenko]

On Sat, Dec 8, 2018 at 11:46 PM Sinan Kaya <okaya@kernel.org> wrote:
>
> We are compiling PCI code today for systems with ACPI and no PCI
> device present. Remove the useless code and reduce the tight
> dependency.

> +#ifdef CONFIG_PCI
>  struct pci_dev *acpi_get_pci_dev(acpi_handle);
> +#else
> +static inline struct pci_dev *acpi_get_pci_dev(acpi_handle hndl)

Can you spell handle fully?

> +{
> +       return NULL;
> +}
> +#endif

-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH v2 3/3] PCI/ACPI: allow ACPI to be built without PCI support

[Sinan Kaya]

On 12/9/2018 1:20 AM, Andy Shevchenko wrote:
>> +#ifdef CONFIG_PCI
>>   struct pci_dev *acpi_get_pci_dev(acpi_handle);
>> +#else
>> +static inline struct pci_dev *acpi_get_pci_dev(acpi_handle hndl)
> Can you spell handle fully?
> 

Yeah, I can do that.

Re: [PATCH v2 1/3] ACPI: Allow PCI to be disabled for reboot

[Rafael J. Wysocki]

On Sat, Dec 8, 2018 at 10:47 PM Sinan Kaya <okaya@kernel.org> wrote:
>
> Make PCI reboot conditional on PCI support being present on the kernel
> configuration.
>
> Signed-off-by: Sinan Kaya <okaya@kernel.org>

Same comment as for patch [2/3]: make the subject say clearly that
this is about CONFIG_PCI.

> ---
>  drivers/acpi/reboot.c | 12 +++++++++---
>  1 file changed, 9 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/acpi/reboot.c b/drivers/acpi/reboot.c
> index 6fa9c2a4cfe9..9aa367f098a6 100644
> --- a/drivers/acpi/reboot.c
> +++ b/drivers/acpi/reboot.c
> @@ -7,8 +7,6 @@
>  void acpi_reboot(void)
>  {
>         struct acpi_generic_address *rr;
> -       struct pci_bus *bus0;
> -       unsigned int devfn;
>         u8 reset_value;
>
>         if (acpi_disabled)
> @@ -33,6 +31,11 @@ void acpi_reboot(void)
>          * on a device on bus 0. */
>         switch (rr->space_id) {
>         case ACPI_ADR_SPACE_PCI_CONFIG:
> +       {
> +#ifdef CONFIG_PCI
> +               unsigned int devfn;
> +               struct pci_bus *bus0;
> +
>                 /* The reset register can only live on bus 0. */
>                 bus0 = pci_find_bus(0, 0);
>                 if (!bus0)
> @@ -45,7 +48,10 @@ void acpi_reboot(void)
>                 pci_bus_write_config_byte(bus0, devfn,
>                                 (rr->address & 0xffff), reset_value);
>                 break;
> -
> +#else
> +               return;

Why not "break"?

> +#endif
> +       }
>         case ACPI_ADR_SPACE_SYSTEM_MEMORY:
>         case ACPI_ADR_SPACE_SYSTEM_IO:
>                 printk(KERN_DEBUG "ACPI MEMORY or I/O RESET_REG.\n");
> --

Re: [PATCH v2 1/3] ACPI: Allow PCI to be disabled for reboot

[Sinan Kaya]

On 12/11/2018 5:12 AM, Rafael J. Wysocki wrote:
> On Sat, Dec 8, 2018 at 10:47 PM Sinan Kaya <okaya@kernel.org> wrote:
>>
>> Make PCI reboot conditional on PCI support being present on the kernel
>> configuration.
>>
>> Signed-off-by: Sinan Kaya <okaya@kernel.org>
> 
> Same comment as for patch [2/3]: make the subject say clearly that
> this is about CONFIG_PCI.

Sure

>>          case ACPI_ADR_SPACE_PCI_CONFIG:
>> +       {
>> +#ifdef CONFIG_PCI
>> +               unsigned int devfn;
>> +               struct pci_bus *bus0;
>> +
>>                  /* The reset register can only live on bus 0. */
>>                  bus0 = pci_find_bus(0, 0);
>>                  if (!bus0)
>> @@ -45,7 +48,10 @@ void acpi_reboot(void)
>>                  pci_bus_write_config_byte(bus0, devfn,
>>                                  (rr->address & 0xffff), reset_value);
>>                  break;
>> -
>> +#else
>> +               return;
> 
> Why not "break"?
> 

I struggled between break and return. Existing code seems to return on failure
when bus0 is NULL. I assumed it would be more logical to return as someone could
put some code after here that assumes everything is in order.

Re: [PATCH v2 1/3] ACPI: Allow PCI to be disabled for reboot

[Rafael J. Wysocki]

On Tue, Dec 11, 2018 at 5:54 PM Sinan Kaya <okaya@kernel.org> wrote:
>
> On 12/11/2018 5:12 AM, Rafael J. Wysocki wrote:
> > On Sat, Dec 8, 2018 at 10:47 PM Sinan Kaya <okaya@kernel.org> wrote:
> >>
> >> Make PCI reboot conditional on PCI support being present on the kernel
> >> configuration.
> >>
> >> Signed-off-by: Sinan Kaya <okaya@kernel.org>
> >
> > Same comment as for patch [2/3]: make the subject say clearly that
> > this is about CONFIG_PCI.
>
> Sure
>
> >>          case ACPI_ADR_SPACE_PCI_CONFIG:
> >> +       {
> >> +#ifdef CONFIG_PCI
> >> +               unsigned int devfn;
> >> +               struct pci_bus *bus0;
> >> +
> >>                  /* The reset register can only live on bus 0. */
> >>                  bus0 = pci_find_bus(0, 0);
> >>                  if (!bus0)
> >> @@ -45,7 +48,10 @@ void acpi_reboot(void)
> >>                  pci_bus_write_config_byte(bus0, devfn,
> >>                                  (rr->address & 0xffff), reset_value);
> >>                  break;
> >> -
> >> +#else
> >> +               return;
> >
> > Why not "break"?
> >
>
> I struggled between break and return. Existing code seems to return on failure
> when bus0 is NULL. I assumed it would be more logical to return as someone could
> put some code after here that assumes everything is in order.

Well, there's no such code ATM, so there's no practical difference
between the two and you don't really need the #else branch at all, do
you?

Re: [PATCH v2 1/3] ACPI: Allow PCI to be disabled for reboot

[Sinan Kaya]

On 12/11/2018 4:49 PM, Rafael J. Wysocki wrote:
>> I struggled between break and return. Existing code seems to return on failure
>> when bus0 is NULL. I assumed it would be more logical to return as someone could
>> put some code after here that assumes everything is in order.
> Well, there's no such code ATM, so there's no practical difference
> between the two and you don't really need the #else branch at all, do
> you?
> 

OK. I'll go with break.