Subject: [RFC PATCH 10/11] PCI/MSI: Split the generic MSI code into new file

From: [email-masked] (Yijing Wang)
Date: Wed, 20 Aug 2014 14:43:05 +0800

> +int msi_capability_init(struct msi_irqs *msi, int nvec)
>> +{
>> +	struct msi_desc *entry;
>> +	int ret;
>> +	unsigned mask;
>> +
>> +	msi_set_enable(msi, 0, MSI_TYPE);	/* Disable MSI during set up */
>> +
>> +	/* MSI Entry Initialization */
>> +	entry = msi_setup_entry(msi);
>> +	if (!entry)
>> +		return -ENOMEM;
>> +
>> +	/* All MSIs are unmasked by default, Mask them all */
> 
> Will this be true for non-pci devices as well?

In my opinion, yes, I think all msi devices should be masked during the setup.
Of course, mask and unmask functions will be override by private mask/unmask functions.

> 
> Thanks
> -Bharat
> 
>> +	mask = msi_mask(entry->msi_attrib.multi_cap);
>> +	msi_mask_irq(entry, mask, mask);
>> +
>> +	/* Configure MSI capability structure */
>> +	ret = arch_setup_msi_irqs(msi, nvec, MSI_TYPE);
>> +	if (ret)
>> +		goto err;
>> +
>> +	/* Set MSI enabled bits	 */
>> +	msi_set_intx(msi, 0);
>> +	msi_set_enable(msi, 1, MSI_TYPE);
>> +	msi->msi_enabled = 1;
>> +
>> +	return 0;
>> +
>> +err:
>> +	msi_mask_irq(entry, mask, ~mask);
>> +	free_msi_irqs(msi);
>> +	return ret;
>> +}
>> +
>> +static void msix_program_entries(struct msi_irqs *msi,
>> +				 struct msix_entry *entries)
>> +{
>> +	struct msi_desc *entry;
>> +	int i = 0;
>> +
>> +	list_for_each_entry(entry, &msi->msi_list, list) {
>> +		entries[i].vector = entry->irq;
>> +		irq_set_msi_desc(entry->irq, entry);
>> +		i++;
>> +	}
>> +}
>> +
>> +/**
>> + * msix_capability_init - configure device's MSI-X capability
>> + * @dev: pointer to the pci_dev data structure of MSI-X device function
>> + * @entries: pointer to an array of struct msix_entry entries
>> + * @nvec: number of @entries
>> + *
>> + * Setup the MSI-X capability structure of device function with a
>> + * single MSI-X irq. A return of zero indicates the successful setup of
>> + * requested MSI-X entries with allocated irqs or non-zero for otherwise.
>> + **/
>> +int msix_capability_init(struct msi_irqs *msi, void __iomem *base,
>> +				struct msix_entry *entries, int nvec)
>> +{
>> +	int ret;
>> +
>> +	/* Ensure MSI-X is disabled while it is set up */
>> +	msi_set_enable(msi, 0, MSIX_TYPE);
>> +
>> +	ret = msix_setup_entries(msi, base, entries, nvec);
>> +	if (ret)
>> +		return ret;
>> +
>> +	ret = arch_setup_msi_irqs(msi, nvec, MSIX_TYPE);
>> +	if (ret)
>> +		goto out_avail;
>> +
>> +	msix_program_entries(msi, entries);
>> +
>> +	/* Set MSI-X enabled bits and unmask the function */
>> +	msi_set_intx(msi, 0);
>> +	msi->msix_enabled = 1;
>> +
>> +	msi_set_enable(msi, 1, MSIX_TYPE);
>> +
>> +	return 0;
>> +
>> +out_avail:
>> +	if (ret < 0) {
>> +		/*
>> +		 * If we had some success, report the number of irqs
>> +		 * we succeeded in setting up.
>> +		 */
>> +		struct msi_desc *entry;
>> +		int avail = 0;
>> +
>> +		list_for_each_entry(entry, &msi->msi_list, list) {
>> +			if (entry->irq != 0)
>> +				avail++;
>> +		}
>> +		if (avail != 0)
>> +			ret = avail;
>> +	}
>> +
>> +	free_msi_irqs(msi);
>> +
>> +	return ret;
>> +}
>> +
>> diff --git a/drivers/pci/Kconfig b/drivers/pci/Kconfig
>> index 893503f..1a10488 100644
>> --- a/drivers/pci/Kconfig
>> +++ b/drivers/pci/Kconfig
>> @@ -2,10 +2,10 @@
>>  # PCI configuration
>>  #
>>  config PCI_MSI
>> -	bool "Message Signaled Interrupts (MSI and MSI-X)"
>> -	depends on PCI
>> +	bool "PCI Message Signaled Interrupts (MSI and MSI-X)"
>> +	depends on PCI && MSI
>>  	help
>> -	   This allows device drivers to enable MSI (Message Signaled
>> +	   This allows PCI device drivers to enable MSI (Message Signaled
>>  	   Interrupts).  Message Signaled Interrupts enable a device to
>>  	   generate an interrupt using an inbound Memory Write on its
>>  	   PCI bus instead of asserting a device IRQ pin.
>> diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c
>> index f0c5989..df7223c 100644
>> --- a/drivers/pci/msi.c
>> +++ b/drivers/pci/msi.c
>> @@ -26,121 +26,8 @@ static int pci_msi_enable = 1;
>>
>>  #define msix_table_size(flags)	((flags & PCI_MSIX_FLAGS_QSIZE) + 1)
>>
>> -
>> -/* Arch hooks */
>> -
>> -int __weak arch_setup_msi_irq(struct msi_irqs *msi, struct msi_desc *desc)
>> -{
>> -	struct pci_dev *dev = msi->data; //TO BE DONE: rework msi_chip to support
>> Non-PCI
>> -	struct msi_chip *chip = dev->bus->msi;
>> -	int err;
>> -
>> -	if (!chip || !chip->setup_irq)
>> -		return -EINVAL;
>> -
>> -	err = chip->setup_irq(chip, dev, desc);
>> -	if (err < 0)
>> -		return err;
>> -
>> -	irq_set_chip_data(desc->irq, chip);
>> -
>> -	return 0;
>> -}
>> -
>> -void __weak arch_teardown_msi_irq(unsigned int irq)
>> -{
>> -	struct msi_chip *chip = irq_get_chip_data(irq);
>> -
>> -	if (!chip || !chip->teardown_irq)
>> -		return;
>> -
>> -	chip->teardown_irq(chip, irq);
>> -}
>> -
>> -int __weak arch_msi_check_device(struct msi_irqs *msi, int nvec, int type)
>> -{
>> -	struct pci_dev *dev = msi->data; //TO BE DONE: rework msi_chip to support
>> Non-PCI
>> -	struct msi_chip *chip = dev->bus->msi;
>> -
>> -	if (!chip || !chip->check_device)
>> -		return 0;
>> -
>> -	return chip->check_device(chip, dev, nvec, type);
>> -}
>> -
>> -int __weak arch_setup_msi_irqs(struct msi_irqs *msi, int nvec, int type)
>> -{
>> -	struct msi_desc *entry;
>> -	int ret;
>> -
>> -	/*
>> -	 * If an architecture wants to support multiple MSI, it needs to
>> -	 * override arch_setup_msi_irqs()
>> -	 */
>> -	if (type == MSI_TYPE && nvec > 1)
>> -		return 1;
>> -
>> -	list_for_each_entry(entry, &msi->msi_list, list) {
>> -		ret = arch_setup_msi_irq(msi, entry);
>> -		if (ret < 0)
>> -			return ret;
>> -		if (ret > 0)
>> -			return -ENOSPC;
>> -	}
>> -
>> -	return 0;
>> -}
>> -
>> -/*
>> - * We have a default implementation available as a separate non-weak
>> - * function, as it is used by the Xen x86 PCI code
>> - */
>> -void default_teardown_msi_irqs(struct msi_irqs *msi)
>> -{
>> -	struct msi_desc *entry;
>> -
>> -	list_for_each_entry(entry, &msi->msi_list, list) {
>> -		int i, nvec;
>> -		if (entry->irq == 0)
>> -			continue;
>> -		if (entry->nvec_used)
>> -			nvec = entry->nvec_used;
>> -		else
>> -			nvec = 1 << entry->msi_attrib.multiple;
>> -		for (i = 0; i < nvec; i++)
>> -			arch_teardown_msi_irq(entry->irq + i);
>> -	}
>> -}
>> -
>> -void __weak arch_teardown_msi_irqs(struct msi_irqs *msi)
>> -{
>> -	return default_teardown_msi_irqs(msi);
>> -}
>> -
>> -static void default_restore_msi_irq(struct msi_irqs *msi, int irq)
>> -{
>> -	struct msi_desc *entry;
>> -
>> -	entry = NULL;
>> -	if (msi->msix_enabled) {
>> -		list_for_each_entry(entry, &msi->msi_list, list) {
>> -			if (irq == entry->irq)
>> -				break;
>> -		}
>> -	} else if (msi->msi_enabled)  {
>> -		entry = irq_get_msi_desc(irq);
>> -	}
>> -
>> -	if (entry)
>> -		write_msi_msg(irq, &entry->msg);
>> -}
>> -
>> -void __weak arch_restore_msi_irqs(struct msi_irqs *msi)
>> -{
>> -	return default_restore_msi_irqs(msi);
>> -}
>> -
>> -static void msix_clear_and_set_ctrl(struct pci_dev *dev, u16 clear, u16 set)
>> +static void msix_clear_and_set_ctrl(struct pci_dev *dev,
>> +		u16 clear, u16 set)
>>  {
>>  	u16 ctrl;
>>
>> @@ -150,7 +37,7 @@ static void msix_clear_and_set_ctrl(struct pci_dev *dev, u16
>> clear, u16 set)
>>  	pci_write_config_word(dev, dev->msix_cap + PCI_MSIX_FLAGS, ctrl);
>>  }
>>
>> -static void msi_set_enable(struct msi_irqs *msi, int enable, int type)
>> +static void pci_msi_set_enable(struct msi_irqs *msi, int enable, int type)
>>  {
>>  	u16 control;
>>  	struct pci_dev *dev = msi->data;
>> @@ -169,21 +56,13 @@ static void msi_set_enable(struct msi_irqs *msi, int
>> enable, int type)
>>  	}
>>  }
>>
>> -static inline __attribute_const__ u32 msi_mask(unsigned x)
>> -{
>> -	/* Don't shift by >= width of type */
>> -	if (x >= 5)
>> -		return 0xffffffff;
>> -	return (1 << (1 << x)) - 1;
>> -}
>> -
>>  /*
>>   * PCI 2.3 does not specify mask bits for each MSI interrupt.  Attempting to
>>   * mask all MSI interrupts by clearing the MSI enable bit does not work
>>   * reliably as devices without an INTx disable bit will then generate a
>>   * level IRQ which will never be cleared.
>>   */
>> -u32 default_msi_mask_irq(struct msi_desc *desc, u32 mask, u32 flag)
>> +u32 pci_msi_mask_irq(struct msi_desc *desc, u32 mask, u32 flag)
>>  {
>>  	struct pci_dev *dev = desc->msi->data;
>>  	u32 mask_bits = desc->masked;
>> @@ -198,16 +77,6 @@ u32 default_msi_mask_irq(struct msi_desc *desc, u32 mask,
>> u32 flag)
>>  	return mask_bits;
>>  }
>>
>> -__weak u32 arch_msi_mask_irq(struct msi_desc *desc, u32 mask, u32 flag)
>> -{
>> -	return default_msi_mask_irq(desc, mask, flag);
>> -}
>> -
>> -static void msi_mask_irq(struct msi_desc *desc, u32 mask, u32 flag)
>> -{
>> -	desc->masked = arch_msi_mask_irq(desc, mask, flag);
>> -}
>> -
>>  /*
>>   * This internal function does not flush PCI writes to the device.
>>   * All users must ensure that they read from the device before either
>> @@ -215,7 +84,7 @@ static void msi_mask_irq(struct msi_desc *desc, u32 mask, u32
>> flag)
>>   * file.  This saves a few milliseconds when initialising devices with lots
>>   * of MSI-X interrupts.
>>   */
>> -u32 default_msix_mask_irq(struct msi_desc *desc, u32 flag)
>> +u32 pci_msix_mask_irq(struct msi_desc *desc, u32 flag)
>>  {
>>  	u32 mask_bits = desc->masked;
>>  	unsigned offset = desc->msi_attrib.entry_nr * PCI_MSIX_ENTRY_SIZE +
>> @@ -228,40 +97,7 @@ u32 default_msix_mask_irq(struct msi_desc *desc, u32 flag)
>>  	return mask_bits;
>>  }
>>
>> -__weak u32 arch_msix_mask_irq(struct msi_desc *desc, u32 flag)
>> -{
>> -	return default_msix_mask_irq(desc, flag);
>> -}
>> -
>> -static void msix_mask_irq(struct msi_desc *desc, u32 flag)
>> -{
>> -	desc->masked = arch_msix_mask_irq(desc, flag);
>> -}
>> -
>> -static void msi_set_mask_bit(struct irq_data *data, u32 flag)
>> -{
>> -	struct msi_desc *desc = irq_data_get_msi(data);
>> -
>> -	if (desc->msi_attrib.is_msix) {
>> -		msix_mask_irq(desc, flag);
>> -		readl(desc->mask_base);		/* Flush write to device */
>> -	} else {
>> -		unsigned offset = data->irq - desc->irq;
>> -		msi_mask_irq(desc, 1 << offset, flag << offset);
>> -	}
>> -}
>> -
>> -void mask_msi_irq(struct irq_data *data)
>> -{
>> -	msi_set_mask_bit(data, 1);
>> -}
>> -
>> -void unmask_msi_irq(struct irq_data *data)
>> -{
>> -	msi_set_mask_bit(data, 0);
>> -}
>> -
>> -static void msix_set_all_mask(struct msi_irqs *msi, int flag)
>> +static void pci_msix_set_all_mask(struct msi_irqs *msi, int flag)
>>  {
>>  	struct pci_dev *dev = msi->data;
>>
>> @@ -271,16 +107,7 @@ static void msix_set_all_mask(struct msi_irqs *msi, int
>> flag)
>>  		msix_clear_and_set_ctrl(dev, PCI_MSIX_FLAGS_MASKALL, 0);
>>  }
>>
>> -void default_restore_msi_irqs(struct msi_irqs *msi)
>> -{
>> -	struct msi_desc *entry;
>> -
>> -	list_for_each_entry(entry, &msi->msi_list, list) {
>> -		default_restore_msi_irq(msi, entry->irq);
>> -	}
>> -}
>> -
>> -void __read_msi_msg(struct msi_desc *entry, struct msi_msg *msg)
>> +void pci_read_msi_msg(struct msi_desc *entry, struct msi_msg *msg)
>>  {
>>  	struct pci_dev *dev = entry->msi->data;
>>
>> @@ -311,31 +138,7 @@ void __read_msi_msg(struct msi_desc *entry, struct msi_msg
>> *msg)
>>  	}
>>  }
>>
>> -void read_msi_msg(unsigned int irq, struct msi_msg *msg)
>> -{
>> -	struct msi_desc *entry = irq_get_msi_desc(irq);
>> -
>> -	__read_msi_msg(entry, msg);
>> -}
>> -
>> -void __get_cached_msi_msg(struct msi_desc *entry, struct msi_msg *msg)
>> -{
>> -	/* Assert that the cache is valid, assuming that
>> -	 * valid messages are not all-zeroes. */
>> -	BUG_ON(!(entry->msg.address_hi | entry->msg.address_lo |
>> -		 entry->msg.data));
>> -
>> -	*msg = entry->msg;
>> -}
>> -
>> -void get_cached_msi_msg(unsigned int irq, struct msi_msg *msg)
>> -{
>> -	struct msi_desc *entry = irq_get_msi_desc(irq);
>> -
>> -	__get_cached_msi_msg(entry, msg);
>> -}
>> -
>> -void __write_msi_msg(struct msi_desc *entry, struct msi_msg *msg)
>> +void pci_write_msi_msg(struct msi_desc *entry, struct msi_msg *msg)
>>  {
>>  	struct pci_dev *dev = entry->msi->data;
>>
>> @@ -373,13 +176,6 @@ void __write_msi_msg(struct msi_desc *entry, struct msi_msg
>> *msg)
>>  	entry->msg = *msg;
>>  }
>>
>> -void write_msi_msg(unsigned int irq, struct msi_msg *msg)
>> -{
>> -	struct msi_desc *entry = irq_get_msi_desc(irq);
>> -
>> -	__write_msi_msg(entry, msg);
>> -}
>> -
>>  static void free_msi_sysfs(struct pci_dev *dev)
>>  {
>>  	struct attribute **msi_attrs;
>> @@ -403,58 +199,6 @@ static void free_msi_sysfs(struct pci_dev *dev)
>>  	}
>>  }
>>
>> -static void free_msi_irqs(struct msi_irqs *msi)
>> -{
>> -	struct msi_desc *entry, *tmp;
>> -
>> -	list_for_each_entry(entry, &msi->msi_list, list) {
>> -		int i, nvec;
>> -		if (!entry->irq)
>> -			continue;
>> -		if (entry->nvec_used)
>> -			nvec = entry->nvec_used;
>> -		else
>> -			nvec = 1 << entry->msi_attrib.multiple;
>> -		for (i = 0; i < nvec; i++)
>> -			BUG_ON(irq_has_action(entry->irq + i));
>> -	}
>> -
>> -	arch_teardown_msi_irqs(msi);
>> -
>> -	list_for_each_entry_safe(entry, tmp, &msi->msi_list, list) {
>> -		if (entry->msi_attrib.is_msix) {
>> -			if (list_is_last(&entry->list, &msi->msi_list))
>> -				iounmap(entry->mask_base);
>> -		}
>> -
>> -		/*
>> -		 * Its possible that we get into this path
>> -		 * When populate_msi_sysfs fails, which means the entries
>> -		 * were not registered with sysfs.  In that case don't
>> -		 * unregister them.
>> -		 */
>> -		if (entry->kobj.parent) {
>> -			kobject_del(&entry->kobj);
>> -			kobject_put(&entry->kobj);
>> -		}
>> -
>> -		list_del(&entry->list);
>> -		kfree(entry);
>> -	}
>> -}
>> -
>> -static struct msi_desc *alloc_msi_entry(struct msi_irqs *msi)
>> -{
>> -	struct msi_desc *desc = kzalloc(sizeof(*desc), GFP_KERNEL);
>> -	if (!desc)
>> -		return NULL;
>> -
>> -	INIT_LIST_HEAD(&desc->list);
>> -	desc->msi = msi;
>> -
>> -	return desc;
>> -}
>> -
>>  static void pci_intx_for_msi(struct msi_irqs *msi, int enable)
>>  {
>>  	struct pci_dev *dev = msi->data;
>> @@ -474,7 +218,7 @@ static void __pci_restore_msi_state(struct pci_dev *dev)
>>  	entry = irq_get_msi_desc(dev->irq);
>>
>>  	pci_intx_for_msi(dev->msi, 0);
>> -	msi_set_enable(dev->msi, 0, MSI_TYPE);
>> +	pci_msi_set_enable(dev->msi, 0, MSI_TYPE);
>>  	arch_restore_msi_irqs(dev->msi);
>>
>>  	pci_read_config_word(dev, dev->msi_cap + PCI_MSI_FLAGS, &control);
>> @@ -496,13 +240,13 @@ static void __pci_restore_msix_state(struct pci_dev *dev)
>>
>>  	/* route the table */
>>  	pci_intx_for_msi(msi, 0);
>> -	msi_set_enable(msi, 1, MSIX_TYPE);
>> -	msix_set_all_mask(msi, 1);
>> +	pci_msi_set_enable(msi, 1, MSIX_TYPE);
>> +	pci_msix_set_all_mask(msi, 1);
>>  	arch_restore_msi_irqs(msi);
>>  	list_for_each_entry(entry, &msi->msi_list, list)
>>  		msix_mask_irq(entry, entry->masked);
>>
>> -	msix_set_all_mask(msi, 0);
>> +	pci_msix_set_all_mask(msi, 0);
>>  }
>>
>>  void pci_restore_msi_state(struct pci_dev *dev)
>> @@ -606,22 +350,16 @@ error_attrs:
>>  	return ret;
>>  }
>>
>> -static struct msi_desc *msi_setup_entry(struct msi_irqs *msi)
>> +static struct msi_desc *pci_msi_setup_entry(struct msi_irqs *msi,
>> +		struct msi_desc *entry)
>>  {
>>  	u16 control;
>> -	struct msi_desc *entry;
>>  	struct pci_dev *dev = msi->data;
>>
>>  	/* MSI Entry Initialization */
>> -	entry = alloc_msi_entry(msi);
>> -	if (!entry)
>> -		return NULL;
>> -
>>  	pci_read_config_word(dev, dev->msi_cap + PCI_MSI_FLAGS, &control);
>>
>> -	entry->msi_attrib.is_msix	= 0;
>>  	entry->msi_attrib.is_64		= !!(control & PCI_MSI_FLAGS_64BIT);
>> -	entry->msi_attrib.entry_nr	= 0;
>>  	entry->msi_attrib.maskbit	= !!(control & PCI_MSI_FLAGS_MASKBIT);
>>  	entry->msi_attrib.default_irq	= dev->irq;	/* Save IOAPIC IRQ */
>>  	entry->msi_attrib.multi_cap	= (control & PCI_MSI_FLAGS_QMASK) >> 1;
>> @@ -638,52 +376,6 @@ static struct msi_desc *msi_setup_entry(struct msi_irqs
>> *msi)
>>  	return entry;
>>  }
>>
>> -/**
>> - * msi_capability_init - configure device's MSI capability structure
>> - * @dev: pointer to the pci_dev data structure of MSI device function
>> - * @nvec: number of interrupts to allocate
>> - *
>> - * Setup the MSI capability structure of the device with the requested
>> - * number of interrupts.  A return value of zero indicates the successful
>> - * setup of an entry with the new MSI irq.  A negative return value indicates
>> - * an error, and a positive return value indicates the number of interrupts
>> - * which could have been allocated.
>> - */
>> -static int msi_capability_init(struct msi_irqs *msi, int nvec)
>> -{
>> -	struct msi_desc *entry;
>> -	int ret;
>> -	unsigned mask;
>> -
>> -	msi_set_enable(msi, 0, MSI_TYPE);	/* Disable MSI during set up */
>> -
>> -	entry = msi_setup_entry(msi);
>> -	if (!entry)
>> -		return -ENOMEM;
>> -
>> -	/* All MSIs are unmasked by default, Mask them all */
>> -	mask = msi_mask(entry->msi_attrib.multi_cap);
>> -	msi_mask_irq(entry, mask, mask);
>> -
>> -	list_add_tail(&entry->list, &msi->msi_list);
>> -
>> -	/* Configure MSI capability structure */
>> -	ret = arch_setup_msi_irqs(msi, nvec, MSI_TYPE);
>> -	if (ret)
>> -		goto err;
>> -
>> -	/* Set MSI enabled bits	 */
>> -	pci_intx_for_msi(msi, 0);
>> -	msi_set_enable(msi, 1, MSI_TYPE);
>> -	msi->msi_enabled = 1;
>> -	return 0;
>> -
>> -err:
>> -	msi_mask_irq(entry, mask, ~mask);
>> -	free_msi_irqs(msi);
>> -	return ret;
>> -}
>> -
>>  static void __iomem *msix_map_region(struct pci_dev *dev, unsigned nr_entries)
>>  {
>>  	resource_size_t phys_addr;
>> @@ -699,28 +391,19 @@ static void __iomem *msix_map_region(struct pci_dev *dev,
>> unsigned nr_entries)
>>  	return ioremap_nocache(phys_addr, nr_entries * PCI_MSIX_ENTRY_SIZE);
>>  }
>>
>> -static int msix_setup_entries(struct msi_irqs *msi, void __iomem *base,
>> -			      struct msix_entry *entries, int nvec)
>> +static int pci_msix_setup_entries(struct msi_irqs *msi, struct msix_entry
>> *entries)
>>  {
>> +	int offset, i = 0;
>>  	struct msi_desc *entry;
>> -	int i, offset;
>>  	struct pci_dev *dev = msi->data;
>>
>> -	for (i = 0; i < nvec; i++) {
>> -		entry = alloc_msi_entry(msi);
>> -		if (!entry) {
>> -			if (!i)
>> -				iounmap(base);
>> -			else
>> -				free_msi_irqs(msi);
>> -			/* No enough memory. Don't try again */
>> -			return -ENOMEM;
>> -		}
>>
>> -		entry->msi_attrib.is_msix	= 1;
>> -		entry->msi_attrib.is_64		= 1;
>> -		entry->msi_attrib.entry_nr	= entries[i].entry;
>> -		entry->mask_base		= base;
>> +	list_for_each_entry(entry, &msi->msi_list, list) {
>> +		/*
>> +		 * Some devices require MSI-X to be enabled before we can touch the
>> +		 * MSI-X registers.  We need to mask all the vectors to prevent
>> +		 * interrupts coming in before they're fully set up.
>> +		 */
>>
>>  		msix_clear_and_set_ctrl(dev, 0,
>>  				PCI_MSIX_FLAGS_MASKALL | PCI_MSIX_FLAGS_ENABLE);
>> @@ -730,87 +413,10 @@ static int msix_setup_entries(struct msi_irqs *msi, void
>> __iomem *base,
>>  		msix_mask_irq(entry, 1);
>>  		msix_clear_and_set_ctrl(dev,
>>  				PCI_MSIX_FLAGS_MASKALL | PCI_MSIX_FLAGS_ENABLE, 0);
>> -
>> -		list_add_tail(&entry->list, &msi->msi_list);
>> -	}
>> -
>> -	return 0;
>> -}
>> -
>> -static void msix_program_entries(struct msi_irqs *msi,
>> -				 struct msix_entry *entries)
>> -{
>> -	struct msi_desc *entry;
>> -	int i = 0;
>> -
>> -	list_for_each_entry(entry, &msi->msi_list, list) {
>> -		entries[i].vector = entry->irq;
>> -		irq_set_msi_desc(entry->irq, entry);
>>  		i++;
>>  	}
>> -}
>> -
>> -/**
>> - * msix_capability_init - configure device's MSI-X capability
>> - * @dev: pointer to the pci_dev data structure of MSI-X device function
>> - * @entries: pointer to an array of struct msix_entry entries
>> - * @nvec: number of @entries
>> - *
>> - * Setup the MSI-X capability structure of device function with a
>> - * single MSI-X irq. A return of zero indicates the successful setup of
>> - * requested MSI-X entries with allocated irqs or non-zero for otherwise.
>> - **/
>> -static int msix_capability_init(struct msi_irqs *msi, void __iomem *base,
>> -				struct msix_entry *entries, int nvec)
>> -{
>> -	int ret;
>> -
>> -	/* Ensure MSI-X is disabled while it is set up */
>> -	msi_set_enable(msi, 0, MSIX_TYPE);
>> -
>> -	ret = msix_setup_entries(msi, base, entries, nvec);
>> -	if (ret)
>> -		return ret;
>> -
>> -	ret = arch_setup_msi_irqs(msi, nvec, MSIX_TYPE);
>> -	if (ret)
>> -		goto out_avail;
>> -
>> -	/*
>> -	 * Some devices require MSI-X to be enabled before we can touch the
>> -	 * MSI-X registers.  We need to mask all the vectors to prevent
>> -	 * interrupts coming in before they're fully set up.
>> -	 */
>> -	msix_program_entries(msi, entries);
>> -
>> -	/* Set MSI-X enabled bits and unmask the function */
>> -	pci_intx_for_msi(msi, 0);
>> -	msi->msix_enabled = 1;
>> -
>> -	msi_set_enable(msi, 1, MSIX_TYPE);
>>
>>  	return 0;
>> -
>> -out_avail:
>> -	if (ret < 0) {
>> -		/*
>> -		 * If we had some success, report the number of irqs
>> -		 * we succeeded in setting up.
>> -		 */
>> -		struct msi_desc *entry;
>> -		int avail = 0;
>> -
>> -		list_for_each_entry(entry, &msi->msi_list, list) {
>> -			if (entry->irq != 0)
>> -				avail++;
>> -		}
>> -		if (avail != 0)
>> -			ret = avail;
>> -	}
>> -
>> -	free_msi_irqs(msi);
>> -
>> -	return ret;
>>  }
>>
>>  /**
>> @@ -886,25 +492,14 @@ EXPORT_SYMBOL(pci_msi_vec_count);
>>  void pci_msi_shutdown(struct pci_dev *dev)
>>  {
>>  	struct msi_desc *desc;
>> -	u32 mask;
>>
>>  	if (!pci_msi_enable || !dev ||
>>  			!pci_dev_msi_enabled(dev, MSI_TYPE))
>>  		return;
>>
>> -	BUG_ON(list_empty(&dev->msi->msi_list));
>> -	desc = list_first_entry(&dev->msi->msi_list, struct msi_desc, list);
>> -
>> -	msi_set_enable(dev->msi, 0, MSI_TYPE);
>> -	pci_intx_for_msi(dev->msi, 1);
>> -	dev->msi->msi_enabled = 0;
>> -
>> -	/* Return the device with MSI unmasked as initial states */
>> -	mask = msi_mask(desc->msi_attrib.multi_cap);
>> -	/* Keep cached state to be restored */
>> -	arch_msi_mask_irq(desc, mask, ~mask);
>> -
>> +	msi_shutdown(dev->msi);
>>  	/* Restore dev->irq to its default pin-assertion irq */
>> +	desc = list_first_entry(&dev->msi->msi_list, struct msi_desc, list);
>>  	dev->irq = desc->msi_attrib.default_irq;
>>  }
>>
>> @@ -1014,20 +609,10 @@ EXPORT_SYMBOL(pci_enable_msix);
>>
>>  void pci_msix_shutdown(struct pci_dev *dev)
>>  {
>> -	struct msi_desc *entry;
>> -
>> -	if (!pci_msi_enable || !dev || !pci_dev_msi_enabled(dev, MSIX_TYPE))
>> +	if (!pci_msi_enable || !dev)
>>  		return;
>>
>> -	/* Return the device with MSI-X masked as initial states */
>> -	list_for_each_entry(entry, &dev->msi->msi_list, list) {
>> -		/* Keep cached states to be restored */
>> -		arch_msix_mask_irq(entry, 1);
>> -	}
>> -
>> -	msi_set_enable(dev->msi, 0, MSIX_TYPE);
>> -	pci_intx_for_msi(dev->msi, 1);
>> -	dev->msi->msix_enabled = 0;
>> +	msix_shutdown(dev->msi);
>>  }
>>
>>  void pci_disable_msix(struct pci_dev *dev)
>> @@ -1060,30 +645,16 @@ int pci_msi_enabled(void)
>>  EXPORT_SYMBOL(pci_msi_enabled);
>>
>>  static struct msi_ops pci_msi = {
>> -	.msi_set_enable = msi_set_enable,
>> -	.msi_setup_entry = msi_setup_entry,
>> -	.msix_setup_entries = msix_setup_entries,
>> -	.msi_mask_irq = default_msi_mask_irq,
>> -	.msix_mask_irq = default_msix_mask_irq,
>> -	.msi_read_message = __read_msi_msg,
>> -	.msi_write_message = __write_msi_msg,
>> +	.msi_set_enable = pci_msi_set_enable,
>> +	.msi_setup_entry = pci_msi_setup_entry,
>> +	.msix_setup_entries = pci_msix_setup_entries,
>> +	.msi_mask_irq = pci_msi_mask_irq,
>> +	.msix_mask_irq = pci_msix_mask_irq,
>> +	.msi_read_message = pci_read_msi_msg,
>> +	.msi_write_message = pci_write_msi_msg,
>>  	.msi_set_intx =  pci_intx_for_msi,
>>  };
>>
>> -struct msi_irqs *alloc_msi_irqs(void *data, struct msi_ops *ops)
>> -{
>> -	struct msi_irqs *msi;
>> -
>> -	msi = kzalloc(sizeof(struct msi_irqs), GFP_KERNEL);
>> -	if (!msi)
>> -		return NULL;
>> -
>> -	INIT_LIST_HEAD(&msi->msi_list);
>> -	msi->data = data;
>> -	msi->ops = ops;
>> -	return msi;
>> -}
>> -
>>  void pci_msi_init_pci_dev(struct pci_dev *dev)
>>  {
>>  	/* Disable the msi hardware to avoid screaming interrupts
>> @@ -1100,10 +671,10 @@ void pci_msi_init_pci_dev(struct pci_dev *dev)
>>
>>  		dev->msi->node = dev_to_node(&dev->dev);
>>  		if (dev->msi_cap)
>> -			msi_set_enable(dev->msi, 0, MSI_TYPE);
>> +			pci_msi_set_enable(dev->msi, 0, MSI_TYPE);
>>
>>  		if (dev->msix_cap)
>> -			msi_set_enable(dev->msi, 0, MSIX_TYPE);
>> +			pci_msi_set_enable(dev->msi, 0, MSIX_TYPE);
>>  	}
>>  }
>>
>> @@ -1224,4 +795,3 @@ int pci_enable_msix_range(struct pci_dev *dev, struct
>> msix_entry *entries,
>>  }
>>  EXPORT_SYMBOL(pci_enable_msix_range);
>>
>> -
>> diff --git a/include/linux/msi.h b/include/linux/msi.h
>> index fc8f3e8..87ed0dd 100644
>> --- a/include/linux/msi.h
>> +++ b/include/linux/msi.h
>> @@ -28,9 +28,9 @@ struct msix_entry {
>>
>>  struct msi_ops {
>>  	void (*msi_set_enable)(struct msi_irqs *msi, int enable, int type);
>> -	struct msi_desc *(*msi_setup_entry)(struct msi_irqs *msi);
>> -	int (*msix_setup_entries)(struct msi_irqs *msi, void __iomem *base,
>> -			struct msix_entry *entries, int nvec);
>> +	struct msi_desc *(*msi_setup_entry)(struct msi_irqs *msi,
>> +			struct msi_desc *entry);
>> +	int (*msix_setup_entries)(struct msi_irqs *msi, struct msix_entry
>> *entries);
>>  	u32 (*msi_mask_irq)(struct msi_desc *desc, u32 mask, u32 flag);
>>  	u32 (*msix_mask_irq)(struct msi_desc *desc, u32 flag);
>>  	void (*msi_read_message)(struct msi_desc *desc, struct msi_msg *msg);
>> @@ -49,6 +49,18 @@ void __write_msi_msg(struct msi_desc *entry, struct msi_msg
>> *msg);
>>  void read_msi_msg(unsigned int irq, struct msi_msg *msg);
>>  void get_cached_msi_msg(unsigned int irq, struct msi_msg *msg);
>>  void write_msi_msg(unsigned int irq, struct msi_msg *msg);
>> +struct msi_desc *alloc_msi_entry(struct msi_irqs *msi);
>> +void msi_mask_irq(struct msi_desc *desc, u32 mask, u32 flag);
>> +void msix_mask_irq(struct msi_desc *desc, u32 flag);
>> +void msi_set_enable(struct msi_irqs *msi, int enable, int type);
>> +
>> +struct msi_irqs *alloc_msi_irqs(void *data, struct msi_ops *ops);
>> +
>> +void free_msi_irqs(struct msi_irqs *msi);
>> +
>> +int msi_capability_init(struct msi_irqs *msi, int nvec);
>> +int msix_capability_init(struct msi_irqs *msi, void __iomem *base,
>> +		struct msix_entry *entries, int nvec);
>>
>>  struct msi_desc {
>>  	struct {
>> @@ -89,12 +101,17 @@ int arch_setup_msi_irqs(struct msi_irqs *msi, int nvec, int
>> type);
>>  void arch_teardown_msi_irqs(struct msi_irqs *msi);
>>  int arch_msi_check_device(struct msi_irqs *msi, int nvec, int type);
>>  void arch_restore_msi_irqs(struct msi_irqs *msi);
>> +u32 arch_msi_mask_irq(struct msi_desc *desc, u32 mask, u32 flag);
>> +u32 arch_msix_mask_irq(struct msi_desc *desc, u32 flag);
>>
>>  void default_teardown_msi_irqs(struct msi_irqs *msi);
>>  void default_restore_msi_irqs(struct msi_irqs *msi);
>>  u32 default_msi_mask_irq(struct msi_desc *desc, u32 mask, u32 flag);
>>  u32 default_msix_mask_irq(struct msi_desc *desc, u32 flag);
>>
>> +void msi_shutdown(struct msi_irqs *msi);
>> +void msix_shutdown(struct msi_irqs *msi);
>> +
>>  #define MSI_TYPE	0x01
>>  #define MSIX_TYPE	0x02
>>
>> @@ -111,4 +128,12 @@ struct msi_chip {
>>  			    int nvec, int type);
>>  };
>>
>> +static inline __attribute_const__ u32 msi_mask(unsigned x)
>> +{
>> +	/* Don't shift by >= width of type */
>> +	if (x >= 5)
>> +		return 0xffffffff;
>> +	return (1 << (1 << x)) - 1;
>> +}
>> +
>>  #endif /* LINUX_MSI_H */
>> --
>> 1.7.1
>>
>> --
>> To unsubscribe from this list: send the line "unsubscribe linux-pci" in
>> the body of a message to majordomo at vger.kernel.org
>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> 
> .
> 

-- 
Thanks!
Yijing