Re: [PATCH 1/2]MSI(X) save/restore for suspend/resume

From: Shaohua Li
Date: Wed Jan 04 2006 - 20:05:51 EST

On Wed, 2006-01-04 at 15:13, Andrew Morton wrote:
> Shaohua Li <shaohua.li@xxxxxxxxx> wrote:
> >
> > Add MSI(X) configure space save/restore in generic PCI helper.
>
> This adds a bunch of code which isn't needed if !CONFIG_PM.
Ok, the updated one fixes this.


Add MSI(X) configure sapce save/restore in generic PCI helper.

---

linux-2.6.15-rc5-root/drivers/pci/msi.c | 213 +++++++++++++++++++++----
linux-2.6.15-rc5-root/drivers/pci/pci.c | 6
linux-2.6.15-rc5-root/drivers/pci/pci.h | 11 +
linux-2.6.15-rc5-root/include/linux/pci.h | 1
linux-2.6.15-rc5-root/include/linux/pci_regs.h | 1
5 files changed, 203 insertions(+), 29 deletions(-)

diff -puN drivers/pci/msi.c~msi_save_restore drivers/pci/msi.c
--- linux-2.6.15-rc5/drivers/pci/msi.c~msi_save_restore 2005-12-22 09:23:16.000000000 +0800
+++ linux-2.6.15-rc5-root/drivers/pci/msi.c 2006-01-05 08:50:11.000000000 +0800
@@ -499,6 +499,187 @@ void pci_scan_msi_device(struct pci_dev
nr_reserved_vectors++;
}

+#ifdef CONFIG_PM
+int pci_save_msi_state(struct pci_dev *dev)
+{
+ int pos, i = 0;
+ u16 control;
+ u32 *cap;
+
+ if ((pos = pci_find_capability(dev, PCI_CAP_ID_MSI)) <= 0 ||
+ dev->no_msi)
+ return 0;
+
+ pci_read_config_word(dev, msi_control_reg(pos), &control);
+ if (!(control & PCI_MSI_FLAGS_ENABLE))
+ return 0;
+
+ cap = kzalloc(sizeof(u32) * 5, GFP_KERNEL);
+ if (!cap) {
+ printk(KERN_ERR "Out of memory in pci_save_msi_state\n");
+ return -ENOMEM;
+ }
+
+ pci_read_config_dword(dev, pos, &cap[i++]);
+ control = cap[0] >> 16;
+ pci_read_config_dword(dev, pos + PCI_MSI_ADDRESS_LO, &cap[i++]);
+ if (control & PCI_MSI_FLAGS_64BIT) {
+ pci_read_config_dword(dev, pos + PCI_MSI_ADDRESS_HI, &cap[i++]);
+ pci_read_config_dword(dev, pos + PCI_MSI_DATA_64, &cap[i++]);
+ } else
+ pci_read_config_dword(dev, pos + PCI_MSI_DATA_32, &cap[i++]);
+ if (control & PCI_MSI_FLAGS_MASKBIT)
+ pci_read_config_dword(dev, pos + PCI_MSI_MASK_BIT, &cap[i++]);
+ dev->saved_cap_space[PCI_CAP_ID_MSI] = cap;
+ disable_msi_mode(dev, pos, PCI_CAP_ID_MSI);
+ return 0;
+}
+
+void pci_restore_msi_state(struct pci_dev *dev)
+{
+ int i = 0, pos;
+ u16 control;
+ u32 *cap = dev->saved_cap_space[PCI_CAP_ID_MSI];
+
+ if (!cap || (pos = pci_find_capability(dev, PCI_CAP_ID_MSI)) <= 0)
+ return;
+
+ control = cap[i++] >> 16;
+ pci_write_config_dword(dev, pos + PCI_MSI_ADDRESS_LO, cap[i++]);
+ if (control & PCI_MSI_FLAGS_64BIT) {
+ pci_write_config_dword(dev, pos + PCI_MSI_ADDRESS_HI, cap[i++]);
+ pci_write_config_dword(dev, pos + PCI_MSI_DATA_64, cap[i++]);
+ } else
+ pci_write_config_dword(dev, pos + PCI_MSI_DATA_32, cap[i++]);
+ if (control & PCI_MSI_FLAGS_MASKBIT)
+ pci_write_config_dword(dev, pos + PCI_MSI_MASK_BIT, cap[i++]);
+ pci_write_config_word(dev, pos + PCI_MSI_FLAGS, control);
+ enable_msi_mode(dev, pos, PCI_CAP_ID_MSI);
+ dev->saved_cap_space[PCI_CAP_ID_MSI] = NULL;
+ kfree(cap);
+}
+
+int pci_save_msix_state(struct pci_dev *dev)
+{
+ int pos;
+ u16 control;
+ u16 *save;
+
+ if ((pos = pci_find_capability(dev, PCI_CAP_ID_MSIX)) <= 0 ||
+ dev->no_msi)
+ return 0;
+
+ pci_read_config_word(dev, msi_control_reg(pos), &control);
+ if (!(control & PCI_MSIX_FLAGS_ENABLE))
+ return 0;
+ save = kmalloc(sizeof(u16), GFP_KERNEL);
+ if (!save) {
+ printk(KERN_ERR "Out of memory in pci_save_msix_state\n");
+ return -ENOMEM;
+ }
+ *save = control;
+ dev->saved_cap_space[PCI_CAP_ID_MSIX] = save;
+ disable_msi_mode(dev, pos, PCI_CAP_ID_MSIX);
+ return 0;
+}
+
+void pci_restore_msix_state(struct pci_dev *dev)
+{
+ u16 *control = dev->saved_cap_space[PCI_CAP_ID_MSIX];
+ u16 save;
+ int pos;
+ int vector, head, tail = 0;
+ void __iomem *base;
+ int j;
+ struct msg_address address;
+ struct msg_data data;
+ struct msi_desc *entry;
+ int temp;
+
+ if (control == NULL)
+ return;
+ save = *control;
+ dev->saved_cap_space[PCI_CAP_ID_MSIX] = NULL;
+ kfree(control);
+ if ((pos = pci_find_capability(dev, PCI_CAP_ID_MSIX)) <= 0)
+ return;
+
+ /* route the table */
+ temp = dev->irq;
+ if (msi_lookup_vector(dev, PCI_CAP_ID_MSIX))
+ return;
+ vector = head = dev->irq;
+ while (head != tail) {
+ entry = msi_desc[vector];
+ base = entry->mask_base;
+ j = entry->msi_attrib.entry_nr;
+
+ msi_address_init(&address);
+ msi_data_init(&data, vector);
+
+ address.lo_address.value &= MSI_ADDRESS_DEST_ID_MASK;
+ address.lo_address.value |= entry->msi_attrib.current_cpu <<
+ MSI_TARGET_CPU_SHIFT;
+
+ writel(address.lo_address.value,
+ base + j * PCI_MSIX_ENTRY_SIZE +
+ PCI_MSIX_ENTRY_LOWER_ADDR_OFFSET);
+ writel(address.hi_address,
+ base + j * PCI_MSIX_ENTRY_SIZE +
+ PCI_MSIX_ENTRY_UPPER_ADDR_OFFSET);
+ writel(*(u32*)&data,
+ base + j * PCI_MSIX_ENTRY_SIZE +
+ PCI_MSIX_ENTRY_DATA_OFFSET);
+
+ tail = msi_desc[vector]->link.tail;
+ vector = tail;
+ }
+ dev->irq = temp;
+
+ pci_write_config_word(dev, msi_control_reg(pos), save);
+ enable_msi_mode(dev, pos, PCI_CAP_ID_MSIX);
+}
+#endif
+
+static void msi_register_init(struct pci_dev *dev, struct msi_desc *entry)
+{
+ struct msg_address address;
+ struct msg_data data;
+ int pos, vector = dev->irq;
+ u16 control;
+
+ pos = pci_find_capability(dev, PCI_CAP_ID_MSI);
+ pci_read_config_word(dev, msi_control_reg(pos), &control);
+ /* Configure MSI capability structure */
+ msi_address_init(&address);
+ msi_data_init(&data, vector);
+ entry->msi_attrib.current_cpu = ((address.lo_address.u.dest_id >>
+ MSI_TARGET_CPU_SHIFT) & MSI_TARGET_CPU_MASK);
+ pci_write_config_dword(dev, msi_lower_address_reg(pos),
+ address.lo_address.value);
+ if (is_64bit_address(control)) {
+ pci_write_config_dword(dev,
+ msi_upper_address_reg(pos), address.hi_address);
+ pci_write_config_word(dev,
+ msi_data_reg(pos, 1), *((u32*)&data));
+ } else
+ pci_write_config_word(dev,
+ msi_data_reg(pos, 0), *((u32*)&data));
+ if (entry->msi_attrib.maskbit) {
+ unsigned int maskbits, temp;
+ /* All MSIs are unmasked by default, Mask them all */
+ pci_read_config_dword(dev,
+ msi_mask_bits_reg(pos, is_64bit_address(control)),
+ &maskbits);
+ temp = (1 << multi_msi_capable(control));
+ temp = ((temp - 1) & ~temp);
+ maskbits |= temp;
+ pci_write_config_dword(dev,
+ msi_mask_bits_reg(pos, is_64bit_address(control)),
+ maskbits);
+ }
+}
+
/**
* msi_capability_init - configure device's MSI capability structure
* @dev: pointer to the pci_dev data structure of MSI device function
@@ -511,8 +692,6 @@ void pci_scan_msi_device(struct pci_dev
static int msi_capability_init(struct pci_dev *dev)
{
struct msi_desc *entry;
- struct msg_address address;
- struct msg_data data;
int pos, vector;
u16 control;

@@ -542,33 +721,8 @@ static int msi_capability_init(struct pc
/* Replace with MSI handler */
irq_handler_init(PCI_CAP_ID_MSI, vector, entry->msi_attrib.maskbit);
/* Configure MSI capability structure */
- msi_address_init(&address);
- msi_data_init(&data, vector);
- entry->msi_attrib.current_cpu = ((address.lo_address.u.dest_id >>
- MSI_TARGET_CPU_SHIFT) & MSI_TARGET_CPU_MASK);
- pci_write_config_dword(dev, msi_lower_address_reg(pos),
- address.lo_address.value);
- if (is_64bit_address(control)) {
- pci_write_config_dword(dev,
- msi_upper_address_reg(pos), address.hi_address);
- pci_write_config_word(dev,
- msi_data_reg(pos, 1), *((u32*)&data));
- } else
- pci_write_config_word(dev,
- msi_data_reg(pos, 0), *((u32*)&data));
- if (entry->msi_attrib.maskbit) {
- unsigned int maskbits, temp;
- /* All MSIs are unmasked by default, Mask them all */
- pci_read_config_dword(dev,
- msi_mask_bits_reg(pos, is_64bit_address(control)),
- &maskbits);
- temp = (1 << multi_msi_capable(control));
- temp = ((temp - 1) & ~temp);
- maskbits |= temp;
- pci_write_config_dword(dev,
- msi_mask_bits_reg(pos, is_64bit_address(control)),
- maskbits);
- }
+ msi_register_init(dev, entry);
+
attach_msi_entry(entry, vector);
/* Set MSI enabled bits */
enable_msi_mode(dev, pos, PCI_CAP_ID_MSI);
@@ -717,6 +871,7 @@ int pci_enable_msi(struct pci_dev* dev)
vector_irq[dev->irq] = -1;
nr_released_vectors--;
spin_unlock_irqrestore(&msi_lock, flags);
+ msi_register_init(dev, msi_desc[dev->irq]);
enable_msi_mode(dev, pos, PCI_CAP_ID_MSI);
return 0;
}
diff -puN drivers/pci/pci.c~msi_save_restore drivers/pci/pci.c
--- linux-2.6.15-rc5/drivers/pci/pci.c~msi_save_restore 2005-12-22 09:23:16.000000000 +0800
+++ linux-2.6.15-rc5-root/drivers/pci/pci.c 2005-12-27 08:42:09.000000000 +0800
@@ -438,6 +438,10 @@ pci_save_state(struct pci_dev *dev)
/* XXX: 100% dword access ok here? */
for (i = 0; i < 16; i++)
pci_read_config_dword(dev, i * 4,&dev->saved_config_space[i]);
+ if ((i = pci_save_msi_state(dev)) != 0)
+ return i;
+ if ((i = pci_save_msix_state(dev)) != 0)
+ return i;
return 0;
}

@@ -452,6 +456,8 @@ pci_restore_state(struct pci_dev *dev)

for (i = 0; i < 16; i++)
pci_write_config_dword(dev,i * 4, dev->saved_config_space[i]);
+ pci_restore_msi_state(dev);
+ pci_restore_msix_state(dev);
return 0;
}

diff -puN drivers/pci/pci.h~msi_save_restore drivers/pci/pci.h
--- linux-2.6.15-rc5/drivers/pci/pci.h~msi_save_restore 2005-12-22 09:23:16.000000000 +0800
+++ linux-2.6.15-rc5-root/drivers/pci/pci.h 2006-01-05 08:51:51.000000000 +0800
@@ -58,6 +58,17 @@ void disable_msi_mode(struct pci_dev *de
#else
static inline void disable_msi_mode(struct pci_dev *dev, int pos, int type) { }
#endif
+#if defined(CONFIG_PCI_MSI) && defined(CONFIG_PM)
+int pci_save_msi_state(struct pci_dev *dev);
+int pci_save_msix_state(struct pci_dev *dev);
+void pci_restore_msi_state(struct pci_dev *dev);
+void pci_restore_msix_state(struct pci_dev *dev);
+#else
+static inline void pci_save_msi_state(struct pci_dev *dev) {}
+static inline void pci_save_msix_state(struct pci_dev *dev) {}
+static inline void pci_restore_msi_state(struct pci_dev *dev) {}
+static inline void pci_restore_msix_state(struct pci_dev *dev) {}
+#endif

extern int pcie_mch_quirk;
extern struct device_attribute pci_dev_attrs[];
diff -puN include/linux/pci.h~msi_save_restore include/linux/pci.h
--- linux-2.6.15-rc5/include/linux/pci.h~msi_save_restore 2005-12-22 09:23:16.000000000 +0800
+++ linux-2.6.15-rc5-root/include/linux/pci.h 2005-12-22 09:23:16.000000000 +0800
@@ -135,6 +135,7 @@ struct pci_dev {
unsigned int block_ucfg_access:1; /* userspace config space access is blocked */

u32 saved_config_space[16]; /* config space saved at suspend time */
+ void *saved_cap_space[PCI_CAP_ID_MAX + 1]; /* ext config space saved at suspend time */
struct bin_attribute *rom_attr; /* attribute descriptor for sysfs ROM entry */
int rom_attr_enabled; /* has display of the rom attribute been enabled? */
struct bin_attribute *res_attr[DEVICE_COUNT_RESOURCE]; /* sysfs file for resources */
diff -puN include/linux/pci_regs.h~msi_save_restore include/linux/pci_regs.h
--- linux-2.6.15-rc5/include/linux/pci_regs.h~msi_save_restore 2005-12-22 09:23:16.000000000 +0800
+++ linux-2.6.15-rc5-root/include/linux/pci_regs.h 2005-12-22 09:23:16.000000000 +0800
@@ -199,6 +199,7 @@
#define PCI_CAP_ID_SHPC 0x0C /* PCI Standard Hot-Plug Controller */
#define PCI_CAP_ID_EXP 0x10 /* PCI Express */
#define PCI_CAP_ID_MSIX 0x11 /* MSI-X */
+#define PCI_CAP_ID_MAX PCI_CAP_ID_MSIX
#define PCI_CAP_LIST_NEXT 1 /* Next capability in the list */
#define PCI_CAP_FLAGS 2 /* Capability defined flags (16 bits) */
#define PCI_CAP_SIZEOF 4
_


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