Re: [PATCH V6 2/5] PCI: Adapt pci_register_io_range() for indirect-IO and PCI I/O translation
From: John Garry
Date: Thu Feb 02 2017 - 12:41:11 EST
Hi Rafael,
Could you kindly check the minor changes to drivers/acpi/pci_root.c? It
would also be appreciated if you could review the ACPI-relevant parts in
lib/extio.c, in [PATCH V5 5/5] LPC: Add the ACPI LPC support
Thanks,
John
On 24/01/2017 07:05, zhichang.yuan wrote:
After indirect-IO is introduced, system must can assigned indirect-IO devices
with logical I/O ranges which are different from those for PCI I/O devices.
Otherwise, I/O accessors can't identify whether the I/O port is for memory
mapped I/O or indirect-IO.
As current helper, pci_register_io_range(), is used for PCI I/O ranges
registration and translation, indirect-IO devices should also apply these
helpers to manage the I/O ranges. It will be easy to ensure the assigned
logical I/O ranges unique.
But for indirect-IO devices, there is no cpu address. The current
pci_register_io_range() can not work for this case.
This patch makes some changes on the pci_register_io_range() to support the
I/O range registration with device's fwnode also. After this, the indirect-IO
devices can register the device-local I/O range to system logical I/O and
easily perform the translation between device-local I/O range and sytem
logical I/O range.
Signed-off-by: zhichang.yuan <yuanzhichang@xxxxxxxxxxxxx>
Signed-off-by: Gabriele Paoloni <gabriele.paoloni@xxxxxxxxxx>
Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
---
drivers/acpi/pci_root.c | 12 +++++-------
drivers/of/address.c | 8 ++------
drivers/pci/pci.c | 44 ++++++++++++++++++++++++++++++++++++++++----
include/linux/pci.h | 7 +++++--
4 files changed, 52 insertions(+), 19 deletions(-)
diff --git a/drivers/acpi/pci_root.c b/drivers/acpi/pci_root.c
index bf601d4..6cadf05 100644
--- a/drivers/acpi/pci_root.c
+++ b/drivers/acpi/pci_root.c
@@ -730,7 +730,8 @@ static void acpi_pci_root_validate_resources(struct device *dev,
}
}
-static void acpi_pci_root_remap_iospace(struct resource_entry *entry)
+static void acpi_pci_root_remap_iospace(struct fwnode_handle *node,
+ struct resource_entry *entry)
{
#ifdef PCI_IOBASE
struct resource *res = entry->res;
@@ -739,11 +740,7 @@ static void acpi_pci_root_remap_iospace(struct resource_entry *entry)
resource_size_t length = resource_size(res);
unsigned long port;
- if (pci_register_io_range(cpu_addr, length))
- goto err;
-
- port = pci_address_to_pio(cpu_addr);
- if (port == (unsigned long)-1)
+ if (pci_register_io_range(node, cpu_addr, length, &port))
goto err;
res->start = port;
@@ -781,7 +778,8 @@ int acpi_pci_probe_root_resources(struct acpi_pci_root_info *info)
else {
resource_list_for_each_entry_safe(entry, tmp, list) {
if (entry->res->flags & IORESOURCE_IO)
- acpi_pci_root_remap_iospace(entry);
+ acpi_pci_root_remap_iospace(&device->fwnode,
+ entry);
if (entry->res->flags & IORESOURCE_DISABLED)
resource_list_destroy_entry(entry);
diff --git a/drivers/of/address.c b/drivers/of/address.c
index 02b2903..d85d228 100644
--- a/drivers/of/address.c
+++ b/drivers/of/address.c
@@ -2,6 +2,7 @@
#define pr_fmt(fmt) "OF: " fmt
#include <linux/device.h>
+#include <linux/fwnode.h>
#include <linux/io.h>
#include <linux/ioport.h>
#include <linux/module.h>
@@ -323,14 +324,9 @@ int of_pci_range_to_resource(struct of_pci_range *range,
if (res->flags & IORESOURCE_IO) {
unsigned long port;
- err = pci_register_io_range(range->cpu_addr, range->size);
+ err = pci_register_io_range(&np->fwnode, range->cpu_addr, range->size, &port);
if (err)
goto invalid_range;
- port = pci_address_to_pio(range->cpu_addr);
- if (port == (unsigned long)-1) {
- err = -EINVAL;
- goto invalid_range;
- }
res->start = port;
} else {
if ((sizeof(resource_size_t) < 8) &&
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index a881c0d..5289221 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -3241,6 +3241,7 @@ int pci_request_regions_exclusive(struct pci_dev *pdev, const char *res_name)
#ifdef PCI_IOBASE
struct io_range {
struct list_head list;
+ struct fwnode_handle *node;
phys_addr_t start;
resource_size_t size;
};
@@ -3253,7 +3254,8 @@ struct io_range {
* Record the PCI IO range (expressed as CPU physical address + size).
* Return a negative value if an error has occured, zero otherwise
*/
-int __weak pci_register_io_range(phys_addr_t addr, resource_size_t size)
+int __weak pci_register_io_range(struct fwnode_handle *node, phys_addr_t addr,
+ resource_size_t size, unsigned long *port)
{
int err = 0;
@@ -3261,10 +3263,31 @@ int __weak pci_register_io_range(phys_addr_t addr, resource_size_t size)
struct io_range *range;
resource_size_t allocated_size = 0;
+ /*
+ * As indirect-IO which support multiple bus instances is introduced,
+ * the input 'addr' is probably not page-aligned. If the PCI I/O
+ * ranges are registered after indirect-IO, there is risk that the
+ * start logical PIO assigned to PCI I/O is not page-aligned.
+ * This will cause some I/O subranges are not remapped or overlapped
+ * in pci_remap_iospace() handling.
+ */
+ WARN_ON(addr != IO_RANGE_IOEXT && !(addr & PAGE_MASK));
+ /*
+ * MMIO will call ioremap, it is better to align size with PAGE_SIZE,
+ * then the return linux virtual PIO is page-aligned.
+ */
+ if (size & PAGE_MASK)
+ size = PAGE_ALIGN(size);
+
/* check if the range hasn't been previously recorded */
spin_lock(&io_range_lock);
list_for_each_entry(range, &io_range_list, list) {
- if (addr >= range->start && addr + size <= range->start + size) {
+ if (node == range->node)
+ goto end_register;
+
+ if (addr != IO_RANGE_IOEXT &&
+ addr >= range->start &&
+ addr + size <= range->start + size) {
/* range already registered, bail out */
goto end_register;
}
@@ -3290,6 +3313,7 @@ int __weak pci_register_io_range(phys_addr_t addr, resource_size_t size)
goto end_register;
}
+ range->node = node;
range->start = addr;
range->size = size;
@@ -3297,6 +3321,14 @@ int __weak pci_register_io_range(phys_addr_t addr, resource_size_t size)
end_register:
spin_unlock(&io_range_lock);
+
+ *port = allocated_size;
+#else
+ /*
+ * powerpc and microblaze have their own registration,
+ * just look up the value here
+ */
+ *port = pci_address_to_pio(addr);
#endif
return err;
@@ -3315,7 +3347,9 @@ phys_addr_t pci_pio_to_address(unsigned long pio)
spin_lock(&io_range_lock);
list_for_each_entry(range, &io_range_list, list) {
- if (pio >= allocated_size && pio < allocated_size + range->size) {
+ if (range->start != IO_RANGE_IOEXT &&
+ pio >= allocated_size &&
+ pio < allocated_size + range->size) {
address = range->start + pio - allocated_size;
break;
}
@@ -3336,7 +3370,9 @@ unsigned long __weak pci_address_to_pio(phys_addr_t address)
spin_lock(&io_range_lock);
list_for_each_entry(res, &io_range_list, list) {
- if (address >= res->start && address < res->start + res->size) {
+ if (res->start != IO_RANGE_IOEXT &&
+ address >= res->start &&
+ address < res->start + res->size) {
addr = address - res->start + offset;
break;
}
diff --git a/include/linux/pci.h b/include/linux/pci.h
index e2d1a12..8d91af8 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -34,6 +34,9 @@
#include <linux/pci_ids.h>
+/* the macro below flags an invalid cpu address
+ * and is used by IO special hosts */
+#define IO_RANGE_IOEXT (resource_size_t)(-1ull)
/*
* The PCI interface treats multi-function devices as independent
* devices. The slot/function address of each device is encoded
@@ -1197,8 +1200,8 @@ int __must_check pci_bus_alloc_resource(struct pci_bus *bus,
resource_size_t),
void *alignf_data);
-
-int pci_register_io_range(phys_addr_t addr, resource_size_t size);
+int pci_register_io_range(struct fwnode_handle *node, phys_addr_t addr,
+ resource_size_t size, unsigned long *port);
unsigned long pci_address_to_pio(phys_addr_t addr);
phys_addr_t pci_pio_to_address(unsigned long pio);
int pci_remap_iospace(const struct resource *res, phys_addr_t phys_addr);