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[PATCH] genirq: msi: implement helper functions read_msi_msg and writ…
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…e_msi_msg

In support of this I also add a struct msi_msg that captures the the two
address and one data field ina typical msi message, and I remember the pos and
if the address is 64bit in struct msi_desc.

This makes the code a little more readable and easier to maintain, and paves
the way to further simplfications.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Rajesh Shah <rajesh.shah@intel.com>
Cc: Andi Kleen <ak@muc.de>
Cc: "Protasevich, Natalie" <Natalie.Protasevich@UNISYS.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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Eric W. Biederman authored and Linus Torvalds committed Oct 4, 2006
1 parent dd159ee commit 0366f8f
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Showing 3 changed files with 104 additions and 106 deletions.
195 changes: 95 additions & 100 deletions drivers/pci/msi.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -87,63 +87,100 @@ static void msi_set_mask_bit(unsigned int vector, int flag)
}
}

#ifdef CONFIG_SMP
static void set_msi_affinity(unsigned int vector, cpumask_t cpu_mask)
static void read_msi_msg(struct msi_desc *entry, struct msi_msg *msg)
{
struct msi_desc *entry;
u32 address_hi, address_lo;
unsigned int irq = vector;
unsigned int dest_cpu = first_cpu(cpu_mask);

entry = (struct msi_desc *)msi_desc[vector];
if (!entry || !entry->dev)
return;
switch(entry->msi_attrib.type) {
case PCI_CAP_ID_MSI:
{
struct pci_dev *dev = entry->dev;
int pos = entry->msi_attrib.pos;
u16 data;

pci_read_config_dword(dev, msi_lower_address_reg(pos),
&msg->address_lo);
if (entry->msi_attrib.is_64) {
pci_read_config_dword(dev, msi_upper_address_reg(pos),
&msg->address_hi);
pci_read_config_word(dev, msi_data_reg(pos, 1), &data);
} else {
msg->address_hi = 0;
pci_read_config_word(dev, msi_data_reg(pos, 1), &data);
}
msg->data = data;
break;
}
case PCI_CAP_ID_MSIX:
{
void __iomem *base;
base = entry->mask_base +
entry->msi_attrib.entry_nr * PCI_MSIX_ENTRY_SIZE;

msg->address_lo = readl(base + PCI_MSIX_ENTRY_LOWER_ADDR_OFFSET);
msg->address_hi = readl(base + PCI_MSIX_ENTRY_UPPER_ADDR_OFFSET);
msg->data = readl(base + PCI_MSIX_ENTRY_DATA_OFFSET);
break;
}
default:
BUG();
}
}

static void write_msi_msg(struct msi_desc *entry, struct msi_msg *msg)
{
switch (entry->msi_attrib.type) {
case PCI_CAP_ID_MSI:
{
int pos = pci_find_capability(entry->dev, PCI_CAP_ID_MSI);

if (!pos)
return;

pci_read_config_dword(entry->dev, msi_upper_address_reg(pos),
&address_hi);
pci_read_config_dword(entry->dev, msi_lower_address_reg(pos),
&address_lo);

msi_ops->target(vector, dest_cpu, &address_hi, &address_lo);

pci_write_config_dword(entry->dev, msi_upper_address_reg(pos),
address_hi);
pci_write_config_dword(entry->dev, msi_lower_address_reg(pos),
address_lo);
set_native_irq_info(irq, cpu_mask);
struct pci_dev *dev = entry->dev;
int pos = entry->msi_attrib.pos;

pci_write_config_dword(dev, msi_lower_address_reg(pos),
msg->address_lo);
if (entry->msi_attrib.is_64) {
pci_write_config_dword(dev, msi_upper_address_reg(pos),
msg->address_hi);
pci_write_config_word(dev, msi_data_reg(pos, 1),
msg->data);
} else {
pci_write_config_word(dev, msi_data_reg(pos, 0),
msg->data);
}
break;
}
case PCI_CAP_ID_MSIX:
{
int offset_hi =
entry->msi_attrib.entry_nr * PCI_MSIX_ENTRY_SIZE +
PCI_MSIX_ENTRY_UPPER_ADDR_OFFSET;
int offset_lo =
entry->msi_attrib.entry_nr * PCI_MSIX_ENTRY_SIZE +
PCI_MSIX_ENTRY_LOWER_ADDR_OFFSET;

address_hi = readl(entry->mask_base + offset_hi);
address_lo = readl(entry->mask_base + offset_lo);

msi_ops->target(vector, dest_cpu, &address_hi, &address_lo);

writel(address_hi, entry->mask_base + offset_hi);
writel(address_lo, entry->mask_base + offset_lo);
set_native_irq_info(irq, cpu_mask);
void __iomem *base;
base = entry->mask_base +
entry->msi_attrib.entry_nr * PCI_MSIX_ENTRY_SIZE;

writel(msg->address_lo,
base + PCI_MSIX_ENTRY_LOWER_ADDR_OFFSET);
writel(msg->address_hi,
base + PCI_MSIX_ENTRY_UPPER_ADDR_OFFSET);
writel(msg->data, base + PCI_MSIX_ENTRY_DATA_OFFSET);
break;
}
default:
break;
BUG();
}
}

#ifdef CONFIG_SMP
static void set_msi_affinity(unsigned int vector, cpumask_t cpu_mask)
{
struct msi_desc *entry;
struct msi_msg msg;
unsigned int irq = vector;
unsigned int dest_cpu = first_cpu(cpu_mask);

entry = (struct msi_desc *)msi_desc[vector];
if (!entry || !entry->dev)
return;

read_msi_msg(entry, &msg);
msi_ops->target(vector, dest_cpu, &msg.address_hi, &msg.address_lo);
write_msi_msg(entry, &msg);
set_native_irq_info(irq, cpu_mask);
}
#else
#define set_msi_affinity NULL
#endif /* CONFIG_SMP */
Expand Down Expand Up @@ -606,23 +643,10 @@ int pci_save_msix_state(struct pci_dev *dev)

vector = head = dev->irq;
while (head != tail) {
int j;
void __iomem *base;
struct msi_desc *entry;

entry = msi_desc[vector];
base = entry->mask_base;
j = entry->msi_attrib.entry_nr;

entry->address_lo_save =
readl(base + j * PCI_MSIX_ENTRY_SIZE +
PCI_MSIX_ENTRY_LOWER_ADDR_OFFSET);
entry->address_hi_save =
readl(base + j * PCI_MSIX_ENTRY_SIZE +
PCI_MSIX_ENTRY_UPPER_ADDR_OFFSET);
entry->data_save =
readl(base + j * PCI_MSIX_ENTRY_SIZE +
PCI_MSIX_ENTRY_DATA_OFFSET);
read_msi_msg(entry, &entry->msg_save);

tail = msi_desc[vector]->link.tail;
vector = tail;
Expand All @@ -639,8 +663,6 @@ void pci_restore_msix_state(struct pci_dev *dev)
u16 save;
int pos;
int vector, head, tail = 0;
void __iomem *base;
int j;
struct msi_desc *entry;
int temp;
struct pci_cap_saved_state *save_state;
Expand All @@ -663,18 +685,7 @@ void pci_restore_msix_state(struct pci_dev *dev)
vector = head = dev->irq;
while (head != tail) {
entry = msi_desc[vector];
base = entry->mask_base;
j = entry->msi_attrib.entry_nr;

writel(entry->address_lo_save,
base + j * PCI_MSIX_ENTRY_SIZE +
PCI_MSIX_ENTRY_LOWER_ADDR_OFFSET);
writel(entry->address_hi_save,
base + j * PCI_MSIX_ENTRY_SIZE +
PCI_MSIX_ENTRY_UPPER_ADDR_OFFSET);
writel(entry->data_save,
base + j * PCI_MSIX_ENTRY_SIZE +
PCI_MSIX_ENTRY_DATA_OFFSET);
write_msi_msg(entry, &entry->msg_save);

tail = msi_desc[vector]->link.tail;
vector = tail;
Expand All @@ -689,29 +700,19 @@ void pci_restore_msix_state(struct pci_dev *dev)
static int msi_register_init(struct pci_dev *dev, struct msi_desc *entry)
{
int status;
u32 address_hi;
u32 address_lo;
u32 data;
struct msi_msg msg;
int pos, vector = dev->irq;
u16 control;

pos = pci_find_capability(dev, PCI_CAP_ID_MSI);
pos = entry->msi_attrib.pos;
pci_read_config_word(dev, msi_control_reg(pos), &control);

/* Configure MSI capability structure */
status = msi_ops->setup(dev, vector, &address_hi, &address_lo, &data);
status = msi_ops->setup(dev, vector, &msg.address_hi, &msg.address_lo, &msg.data);
if (status < 0)
return status;

pci_write_config_dword(dev, msi_lower_address_reg(pos), address_lo);
if (is_64bit_address(control)) {
pci_write_config_dword(dev,
msi_upper_address_reg(pos), address_hi);
pci_write_config_word(dev,
msi_data_reg(pos, 1), data);
} else
pci_write_config_word(dev,
msi_data_reg(pos, 0), data);
write_msi_msg(entry, &msg);
if (entry->msi_attrib.maskbit) {
unsigned int maskbits, temp;
/* All MSIs are unmasked by default, Mask them all */
Expand Down Expand Up @@ -761,9 +762,11 @@ static int msi_capability_init(struct pci_dev *dev)
entry->link.tail = vector;
entry->msi_attrib.type = PCI_CAP_ID_MSI;
entry->msi_attrib.state = 0; /* Mark it not active */
entry->msi_attrib.is_64 = is_64bit_address(control);
entry->msi_attrib.entry_nr = 0;
entry->msi_attrib.maskbit = is_mask_bit_support(control);
entry->msi_attrib.default_vector = dev->irq; /* Save IOAPIC IRQ */
entry->msi_attrib.pos = pos;
dev->irq = vector;
entry->dev = dev;
if (is_mask_bit_support(control)) {
Expand Down Expand Up @@ -801,9 +804,7 @@ static int msix_capability_init(struct pci_dev *dev,
struct msix_entry *entries, int nvec)
{
struct msi_desc *head = NULL, *tail = NULL, *entry = NULL;
u32 address_hi;
u32 address_lo;
u32 data;
struct msi_msg msg;
int status;
int vector, pos, i, j, nr_entries, temp = 0;
unsigned long phys_addr;
Expand Down Expand Up @@ -840,9 +841,11 @@ static int msix_capability_init(struct pci_dev *dev,
entries[i].vector = vector;
entry->msi_attrib.type = PCI_CAP_ID_MSIX;
entry->msi_attrib.state = 0; /* Mark it not active */
entry->msi_attrib.is_64 = 1;
entry->msi_attrib.entry_nr = j;
entry->msi_attrib.maskbit = 1;
entry->msi_attrib.default_vector = dev->irq;
entry->msi_attrib.pos = pos;
entry->dev = dev;
entry->mask_base = base;
if (!head) {
Expand All @@ -861,21 +864,13 @@ static int msix_capability_init(struct pci_dev *dev,
irq_handler_init(PCI_CAP_ID_MSIX, vector, 1);
/* Configure MSI-X capability structure */
status = msi_ops->setup(dev, vector,
&address_hi,
&address_lo,
&data);
&msg.address_hi,
&msg.address_lo,
&msg.data);
if (status < 0)
break;

writel(address_lo,
base + j * PCI_MSIX_ENTRY_SIZE +
PCI_MSIX_ENTRY_LOWER_ADDR_OFFSET);
writel(address_hi,
base + j * PCI_MSIX_ENTRY_SIZE +
PCI_MSIX_ENTRY_UPPER_ADDR_OFFSET);
writel(data,
base + j * PCI_MSIX_ENTRY_SIZE +
PCI_MSIX_ENTRY_DATA_OFFSET);
write_msi_msg(entry, &msg);
attach_msi_entry(entry, vector);
}
if (i != nvec) {
Expand Down
9 changes: 3 additions & 6 deletions drivers/pci/msi.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -130,10 +130,10 @@ struct msi_desc {
__u8 type : 5; /* {0: unused, 5h:MSI, 11h:MSI-X} */
__u8 maskbit : 1; /* mask-pending bit supported ? */
__u8 state : 1; /* {0: free, 1: busy} */
__u8 reserved: 1; /* reserved */
__u8 is_64 : 1; /* Address size: 0=32bit 1=64bit */
__u8 entry_nr; /* specific enabled entry */
__u8 default_vector; /* default pre-assigned vector */
__u8 unused; /* formerly unused destination cpu*/
__u8 pos; /* Location of the msi capability */
}msi_attrib;

struct {
Expand All @@ -146,10 +146,7 @@ struct msi_desc {

#ifdef CONFIG_PM
/* PM save area for MSIX address/data */

u32 address_hi_save;
u32 address_lo_save;
u32 data_save;
struct msi_msg msg_save;
#endif
};

Expand Down
6 changes: 6 additions & 0 deletions include/linux/pci.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -595,6 +595,12 @@ struct msix_entry {
u16 entry; /* driver uses to specify entry, OS writes */
};

struct msi_msg {
u32 address_lo; /* low 32 bits of msi message address */
u32 address_hi; /* high 32 bits of msi message address */
u32 data; /* 16 bits of msi message data */
};

#ifndef CONFIG_PCI_MSI
static inline void pci_scan_msi_device(struct pci_dev *dev) {}
static inline int pci_enable_msi(struct pci_dev *dev) {return -1;}
Expand Down

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