[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-Id: <1376392346-14127-3-git-send-email-treding@nvidia.com>
Date: Tue, 13 Aug 2013 13:12:25 +0200
From: Thierry Reding <thierry.reding@...il.com>
To: Russell King <linux@....linux.org.uk>,
Bjorn Helgaas <bhelgaas@...gle.com>
Cc: Stephen Warren <swarren@...dotorg.org>,
Thomas Petazzoni <thomas.petazzoni@...e-electrons.com>,
Jason Cooper <jason@...edaemon.net>,
Sebastian Hesselbarth <sebastian.hesselbarth@...il.com>,
linux-arm-kernel@...ts.infradead.org, linux-pci@...r.kernel.org,
linux-tegra@...r.kernel.org, linux-kernel@...r.kernel.org,
Thierry Reding <treding@...dia.com>
Subject: [RFC 2/3] ARM: Introduce pci_common_exit()
In order to support building PCI host drivers as modules, functionality
is required to undo the steps performed by pci_common_init(). The PCI
core provides much of the functionality already, so add a function that
can be called by drivers to wrap the ARM specific bits.
This patch does a number of things to achieve this: it adds a .nr field
to struct pci_sys_data to keep track of the controller number that was
used to initialize it during pci_common_init(). That field is passed to
the new .teardown() callback during cleanup to undo what .setup() did.
Furthermore the list of pci_sys_data structures setup can optionally be
returned via the hw_pci structure's .sys field. If a driver initializes
it, then it is assumed to be an empty list that pci_common_init() will
append to. Otherwise the old behaviour of keeping a local list only is
preserved.
If a driver wants to support unloading, then it needs access to this
list and pass it to pci_common_exit(). This will iterate over the list,
call the new .teardown() callback and remove the root bus associated
with each entry.
Signed-off-by: Thierry Reding <treding@...dia.com>
---
arch/arm/include/asm/mach/pci.h | 6 ++++++
arch/arm/kernel/bios32.c | 29 ++++++++++++++++++++++++++---
2 files changed, 32 insertions(+), 3 deletions(-)
diff --git a/arch/arm/include/asm/mach/pci.h b/arch/arm/include/asm/mach/pci.h
index 454d642..d6c352a 100644
--- a/arch/arm/include/asm/mach/pci.h
+++ b/arch/arm/include/asm/mach/pci.h
@@ -25,6 +25,7 @@ struct hw_pci {
struct pci_ops *ops;
int nr_controllers;
void **private_data;
+ struct list_head *sys;
int (*setup)(int nr, struct pci_sys_data *);
struct pci_bus *(*scan)(int nr, struct pci_sys_data *);
void (*preinit)(void);
@@ -38,6 +39,7 @@ struct hw_pci {
resource_size_t align);
void (*add_bus)(struct pci_bus *bus);
void (*remove_bus)(struct pci_bus *bus);
+ void (*teardown)(int nr, struct pci_sys_data *);
};
/*
@@ -49,6 +51,7 @@ struct pci_sys_data {
#endif
struct list_head node;
int busnr; /* primary bus number */
+ int nr; /* controller number */
u64 mem_offset; /* bus->cpu memory mapping offset */
unsigned long io_offset; /* bus->cpu IO mapping offset */
struct pci_bus *bus; /* PCI bus */
@@ -67,6 +70,7 @@ struct pci_sys_data {
resource_size_t align);
void (*add_bus)(struct pci_bus *bus);
void (*remove_bus)(struct pci_bus *bus);
+ void (*teardown)(int nr, struct pci_sys_data *);
void *private_data; /* platform controller private data */
};
@@ -84,6 +88,8 @@ static inline void pci_common_init(struct hw_pci *hw)
pci_common_init_dev(NULL, hw);
}
+void pci_common_exit(struct list_head *head);
+
/*
* Setup early fixed I/O mapping.
*/
diff --git a/arch/arm/kernel/bios32.c b/arch/arm/kernel/bios32.c
index 1ec9c87..6895520 100644
--- a/arch/arm/kernel/bios32.c
+++ b/arch/arm/kernel/bios32.c
@@ -475,11 +475,13 @@ static void pcibios_init_hw(struct device *parent, struct hw_pci *hw,
sys->domain = hw->domain;
#endif
sys->busnr = busnr;
+ sys->nr = nr;
sys->swizzle = hw->swizzle;
sys->map_irq = hw->map_irq;
sys->align_resource = hw->align_resource;
sys->add_bus = hw->add_bus;
sys->remove_bus = hw->remove_bus;
+ sys->teardown = hw->teardown;
INIT_LIST_HEAD(&sys->resources);
if (hw->private_data)
@@ -517,18 +519,24 @@ static void pcibios_init_hw(struct device *parent, struct hw_pci *hw,
void pci_common_init_dev(struct device *parent, struct hw_pci *hw)
{
struct pci_sys_data *sys;
- LIST_HEAD(head);
+ struct list_head *head;
+ LIST_HEAD(list);
+
+ if (hw->sys)
+ head = hw->sys;
+ else
+ head = &list;
pci_add_flags(PCI_REASSIGN_ALL_RSRC);
if (hw->preinit)
hw->preinit();
- pcibios_init_hw(parent, hw, &head);
+ pcibios_init_hw(parent, hw, head);
if (hw->postinit)
hw->postinit();
pci_fixup_irqs(pcibios_swizzle, pcibios_map_irq);
- list_for_each_entry(sys, &head, node) {
+ list_for_each_entry(sys, head, node) {
struct pci_bus *bus = sys->bus;
if (!pci_has_flag(PCI_PROBE_ONLY)) {
@@ -555,6 +563,21 @@ void pci_common_init_dev(struct device *parent, struct hw_pci *hw)
}
}
+void pci_common_exit(struct list_head *head)
+{
+ struct pci_sys_data *sys, *tmp;
+
+ list_for_each_entry_safe(sys, tmp, head, node) {
+ if (sys->teardown)
+ sys->teardown(sys->nr, sys);
+
+ pci_stop_root_bus(sys->bus);
+ pci_remove_root_bus(sys->bus);
+ list_del(&sys->node);
+ kfree(sys);
+ }
+}
+
#ifndef CONFIG_PCI_HOST_ITE8152
void pcibios_set_master(struct pci_dev *dev)
{
--
1.8.3.4
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists