Re: [RFC PATCH 02/16] PCI: Use pci_scan_root_bus() instead of pci_scan_bus()

Yijing Wang
2014-11-19T01:19:44Z

On 2014/11/18 22:28, Liviu Dudau wrote:
> On Mon, Nov 17, 2014 at 10:21:36AM +0000, Yijing Wang wrote:
>> From: Yijing Wang <wangyijing0307@gmail.com>
>>
>> Now we could use pci_scan_root_bus() instead of
>> pci_scan_bus(), pass NULL resources means use the default
>> io/mem.
>
> Actually, I think this patch goes in the wrong direction. You are adding
> two additional parameters that are NULL for every call you replace.
> pci_scan_bus() was actually intended as a "shortcut with defaults" kind
> of call so that you don't have to pass a value for parameters you don't
> care about.
>
> My suggestion would be to keep the function as is and replace the call
> to pci_create_root_bus() inside with the appropriate sequence.

Hmmm, maybe you are right, provide a simple pci scan interfaces
(which don't care parent and resources) is better than use a complex
one with several NULL arguments. :)

>
> Best regards,
> Liviu
>
>>
>> Signed-off-by: Yijing Wang <wangyijing@huawei.com>
>> ---
>> arch/alpha/include/asm/pci.h | 2 +-
>> arch/alpha/kernel/sys_nautilus.c | 2 +-
>> arch/cris/include/asm/pci.h | 2 +-
>> arch/ia64/include/asm/pci.h | 2 +-
>> arch/m68k/coldfire/pci.c | 2 +-
>> arch/mips/include/asm/pci.h | 2 +-
>> arch/mn10300/include/asm/pci.h | 2 +-
>> arch/sh/include/asm/pci.h | 2 +-
>> arch/sparc/include/asm/pci_32.h | 2 +-
>> arch/sparc/include/asm/pci_64.h | 2 +-
>> arch/sparc/kernel/pcic.c | 3 ++-
>> arch/unicore32/kernel/pci.c | 2 +-
>> arch/x86/include/asm/pci.h | 2 +-
>> arch/x86/pci/amd_bus.c | 2 +-
>> arch/xtensa/include/asm/pci.h | 2 +-
>> drivers/parisc/dino.c | 4 ++--
>> drivers/pci/hotplug/ibmphp_core.c | 2 +-
>> 17 files changed, 19 insertions(+), 18 deletions(-)
>>
>> diff --git a/arch/alpha/include/asm/pci.h b/arch/alpha/include/asm/pci.h
>> index f7f680f..157925a 100644
>> --- a/arch/alpha/include/asm/pci.h
>> +++ b/arch/alpha/include/asm/pci.h
>> @@ -49,7 +49,7 @@ struct pci_controller {
>> void *sysdata;
>> };
>>
>> -/* Override the logic in pci_scan_bus for skipping already-configured
>> +/* Override the logic in pci_scan_root_bus for skipping already-configured
>> bus numbers. */
>>
>> #define pcibios_assign_all_busses() 1
>> diff --git a/arch/alpha/kernel/sys_nautilus.c b/arch/alpha/kernel/sys_nautilus.c
>> index 837c0fa..1047ab3 100644
>> --- a/arch/alpha/kernel/sys_nautilus.c
>> +++ b/arch/alpha/kernel/sys_nautilus.c
>> @@ -206,7 +206,7 @@ nautilus_init_pci(void)
>> unsigned long memtop = max_low_pfn << PAGE_SHIFT;
>>
>> /* Scan our single hose. */
>> - bus = pci_scan_bus(0, alpha_mv.pci_ops, hose);
>> + bus = pci_scan_root_bus(NULL, 0, alpha_mv.pci_ops, hose, NULL);
>> hose->bus = bus;
>> pcibios_claim_one_bus(bus);
>>
>> diff --git a/arch/cris/include/asm/pci.h b/arch/cris/include/asm/pci.h
>> index cc2399c..96b33a6 100644
>> --- a/arch/cris/include/asm/pci.h
>> +++ b/arch/cris/include/asm/pci.h
>> @@ -5,7 +5,7 @@
>> #ifdef __KERNEL__
>> #include <linux/mm.h> /* for struct page */
>>
>> -/* Can be used to override the logic in pci_scan_bus for skipping
>> +/* Can be used to override the logic in pci_scan_root_bus for skipping
>> already-configured bus numbers - to be used for buggy BIOSes
>> or architectures with incomplete PCI setup by the loader */
>>
>> diff --git a/arch/ia64/include/asm/pci.h b/arch/ia64/include/asm/pci.h
>> index 52af5ed..64b34d6 100644
>> --- a/arch/ia64/include/asm/pci.h
>> +++ b/arch/ia64/include/asm/pci.h
>> @@ -20,7 +20,7 @@ struct pci_vector_struct {
>> };
>>
>> /*
>> - * Can be used to override the logic in pci_scan_bus for skipping already-configured bus
>> + * Can be used to override the logic in pci_scan_root_bus for skipping already-configured bus
>> * numbers - to be used for buggy BIOSes or architectures with incomplete PCI setup by the
>> * loader.
>> */
>> diff --git a/arch/m68k/coldfire/pci.c b/arch/m68k/coldfire/pci.c
>> index df96792..4d242fb 100644
>> --- a/arch/m68k/coldfire/pci.c
>> +++ b/arch/m68k/coldfire/pci.c
>> @@ -312,7 +312,7 @@ static int __init mcf_pci_init(void)
>> set_current_state(TASK_UNINTERRUPTIBLE);
>> schedule_timeout(msecs_to_jiffies(200));
>>
>> - rootbus = pci_scan_bus(0, &mcf_pci_ops, NULL);
>> + rootbus = pci_scan_root_bus(NULL, 0, &mcf_pci_ops, NULL, NULL);
>> rootbus->resource[0] = &mcf_pci_io;
>> rootbus->resource[1] = &mcf_pci_mem;
>>
>> diff --git a/arch/mips/include/asm/pci.h b/arch/mips/include/asm/pci.h
>> index 974b0e3..212030a 100644
>> --- a/arch/mips/include/asm/pci.h
>> +++ b/arch/mips/include/asm/pci.h
>> @@ -60,7 +60,7 @@ extern void register_pci_controller(struct pci_controller *hose);
>> extern int pcibios_map_irq(const struct pci_dev *dev, u8 slot, u8 pin);
>>
>>
>> -/* Can be used to override the logic in pci_scan_bus for skipping
>> +/* Can be used to override the logic in pci_scan_root_bus for skipping
>> already-configured bus numbers - to be used for buggy BIOSes
>> or architectures with incomplete PCI setup by the loader */
>>
>> diff --git a/arch/mn10300/include/asm/pci.h b/arch/mn10300/include/asm/pci.h
>> index 5f70af2..6305f14 100644
>> --- a/arch/mn10300/include/asm/pci.h
>> +++ b/arch/mn10300/include/asm/pci.h
>> @@ -33,7 +33,7 @@ do { \
>> #define __pcidebug(FMT, BUS, DEVFN, WHERE, ...) do {} while (0)
>> #endif
>>
>> -/* Can be used to override the logic in pci_scan_bus for skipping
>> +/* Can be used to override the logic in pci_scan_root_bus for skipping
>> * already-configured bus numbers - to be used for buggy BIOSes or
>> * architectures with incomplete PCI setup by the loader */
>>
>> diff --git a/arch/sh/include/asm/pci.h b/arch/sh/include/asm/pci.h
>> index 5b45115..69bcb78 100644
>> --- a/arch/sh/include/asm/pci.h
>> +++ b/arch/sh/include/asm/pci.h
>> @@ -3,7 +3,7 @@
>>
>> #ifdef __KERNEL__
>>
>> -/* Can be used to override the logic in pci_scan_bus for skipping
>> +/* Can be used to override the logic in pci_scan_root_bus for skipping
>> already-configured bus numbers - to be used for buggy BIOSes
>> or architectures with incomplete PCI setup by the loader */
>>
>> diff --git a/arch/sparc/include/asm/pci_32.h b/arch/sparc/include/asm/pci_32.h
>> index 53e9b49..4ef6064 100644
>> --- a/arch/sparc/include/asm/pci_32.h
>> +++ b/arch/sparc/include/asm/pci_32.h
>> @@ -5,7 +5,7 @@
>>
>> #include <linux/dma-mapping.h>
>>
>> -/* Can be used to override the logic in pci_scan_bus for skipping
>> +/* Can be used to override the logic in pci_scan_root_bus for skipping
>> * already-configured bus numbers - to be used for buggy BIOSes
>> * or architectures with incomplete PCI setup by the loader.
>> */
>> diff --git a/arch/sparc/include/asm/pci_64.h b/arch/sparc/include/asm/pci_64.h
>> index bd00a62..6e017f9 100644
>> --- a/arch/sparc/include/asm/pci_64.h
>> +++ b/arch/sparc/include/asm/pci_64.h
>> @@ -5,7 +5,7 @@
>>
>> #include <linux/dma-mapping.h>
>>
>> -/* Can be used to override the logic in pci_scan_bus for skipping
>> +/* Can be used to override the logic in pci_scan_root_bus for skipping
>> * already-configured bus numbers - to be used for buggy BIOSes
>> * or architectures with incomplete PCI setup by the loader.
>> */
>> diff --git a/arch/sparc/kernel/pcic.c b/arch/sparc/kernel/pcic.c
>> index 6cc78c2..64aafac 100644
>> --- a/arch/sparc/kernel/pcic.c
>> +++ b/arch/sparc/kernel/pcic.c
>> @@ -390,7 +390,8 @@ static void __init pcic_pbm_scan_bus(struct linux_pcic *pcic)
>> {
>> struct linux_pbm_info *pbm = &pcic->pbm;
>>
>> - pbm->pci_bus = pci_scan_bus(pbm->pci_first_busno, &pcic_ops, pbm);
>> + pbm->pci_bus = pci_scan_root_bus(NULL, pbm->pci_first_busno,
>> + &pcic_ops, pbm, NULL);
>> #if 0 /* deadwood transplanted from sparc64 */
>> pci_fill_in_pbm_cookies(pbm->pci_bus, pbm, pbm->prom_node);
>> pci_record_assignments(pbm, pbm->pci_bus);
>> diff --git a/arch/unicore32/kernel/pci.c b/arch/unicore32/kernel/pci.c
>> index 374a055..be0f261 100644
>> --- a/arch/unicore32/kernel/pci.c
>> +++ b/arch/unicore32/kernel/pci.c
>> @@ -258,7 +258,7 @@ static int __init pci_common_init(void)
>>
>> pci_puv3_preinit();
>>
>> - puv3_bus = pci_scan_bus(0, &pci_puv3_ops, NULL);
>> + puv3_bus = pci_scan_root_bus(NULL, 0, &pci_puv3_ops, NULL, NULL);
>>
>> if (!puv3_bus)
>> panic("PCI: unable to scan bus!");
>> diff --git a/arch/x86/include/asm/pci.h b/arch/x86/include/asm/pci.h
>> index 0892ea0..0540ff7 100644
>> --- a/arch/x86/include/asm/pci.h
>> +++ b/arch/x86/include/asm/pci.h
>> @@ -41,7 +41,7 @@ static inline int pci_proc_domain(struct pci_bus *bus)
>> }
>> #endif
>>
>> -/* Can be used to override the logic in pci_scan_bus for skipping
>> +/* Can be used to override the logic in pci_scan_root_bus for skipping
>> already-configured bus numbers - to be used for buggy BIOSes
>> or architectures with incomplete PCI setup by the loader */
>>
>> diff --git a/arch/x86/pci/amd_bus.c b/arch/x86/pci/amd_bus.c
>> index c20d2cc..baf6209 100644
>> --- a/arch/x86/pci/amd_bus.c
>> +++ b/arch/x86/pci/amd_bus.c
>> @@ -52,7 +52,7 @@ static struct pci_root_info __init *find_pci_root_info(int node, int link)
>>
>> /**
>> * early_root_info_init()
>> - * called before pcibios_scan_root and pci_scan_bus
>> + * called before pcibios_scan_root and pci_scan_root_bus
>> * fills the mp_bus_to_cpumask array based according
>> * to the LDT Bus Number Registers found in the northbridge.
>> */
>> diff --git a/arch/xtensa/include/asm/pci.h b/arch/xtensa/include/asm/pci.h
>> index 5d52dc4..377fae9 100644
>> --- a/arch/xtensa/include/asm/pci.h
>> +++ b/arch/xtensa/include/asm/pci.h
>> @@ -13,7 +13,7 @@
>>
>> #ifdef __KERNEL__
>>
>> -/* Can be used to override the logic in pci_scan_bus for skipping
>> +/* Can be used to override the logic in pci_scan_root_bus for skipping
>> * already-configured bus numbers - to be used for buggy BIOSes
>> * or architectures with incomplete PCI setup by the loader
>> */
>> diff --git a/drivers/parisc/dino.c b/drivers/parisc/dino.c
>> index a0580af..67c31bd 100644
>> --- a/drivers/parisc/dino.c
>> +++ b/drivers/parisc/dino.c
>> @@ -74,7 +74,7 @@
>> ** assigned a PCI bus number based on "when" it's discovered.
>> **
>> ** The "secondary" bus number is set to this before calling
>> -** pci_scan_bus(). If any PPB's are present, the scan will
>> +** pci_scan_root_bus(). If any PPB's are present, the scan will
>> ** discover them and update the "secondary" and "subordinate"
>> ** fields in Dino's pci_bus structure.
>> **
>> @@ -787,7 +787,7 @@ static int __init dino_common_init(struct parisc_device *dev,
>>
>> pcibios_register_hba(&dino_dev->hba);
>>
>> - pci_bios = &dino_bios_ops; /* used by pci_scan_bus() */
>> + pci_bios = &dino_bios_ops;
>> pci_port = &dino_port_ops;
>>
>> /*
>> diff --git a/drivers/pci/hotplug/ibmphp_core.c b/drivers/pci/hotplug/ibmphp_core.c
>> index 3efaf4c..b486432 100644
>> --- a/drivers/pci/hotplug/ibmphp_core.c
>> +++ b/drivers/pci/hotplug/ibmphp_core.c
>> @@ -767,7 +767,7 @@ static u8 bus_structure_fixup(u8 busno)
>> (l != 0x0000) && (l != 0xffff)) {
>> debug("%s - Inside bus_structure_fixup()\n",
>> __func__);
>> - pci_scan_bus(busno, ibmphp_pci_bus->ops, NULL);
>> + pci_scan_root_bus(NULL, busno, ibmphp_pci_bus->ops, NULL, NULL);
>> break;
>> }
>> }
>> --
>> 1.7.1
>>
>> --
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>>
>

--
Thanks!
Yijing