On Wed, Mar 11, 2015 at 9:12 AM, Tomasz Nowicki tomasz.nowicki@linaro.org wrote:
Architectures which want to take advantage of ECAM generic goodness
This is not necessarily an architecture decision. It is likely per host.
should select CONFIG_PCI_ECAM_GENERIC. Otherwise, like x86 32bits machines, are obligated to provide own low-level ECAM calls.
Signed-off-by: Tomasz Nowicki tomasz.nowicki@linaro.org
[...]
diff --git a/drivers/pci/ecam.c b/drivers/pci/ecam.c index c588234..796b6e7 100644 --- a/drivers/pci/ecam.c +++ b/drivers/pci/ecam.c @@ -23,6 +23,119 @@ static DEFINE_MUTEX(pci_mmcfg_lock);
LIST_HEAD(pci_mmcfg_list);
+#ifdef CONFIG_GENERIC_PCI_ECAM +static char __iomem *pci_dev_base(unsigned int seg, unsigned int bus,
unsigned int devfn)
+{
struct pci_mmcfg_region *cfg = pci_mmconfig_lookup(seg, bus);
if (cfg && cfg->virt)
return cfg->virt + (PCI_MMCFG_BUS_OFFSET(bus) | (devfn << 12));
return NULL;
+}
+int pci_mmcfg_read(unsigned int seg, unsigned int bus,
unsigned int devfn, int reg, int len, u32 *value)
+{
char __iomem *addr;
/* Why do we have this when nobody checks it. How about a BUG()!? -AK */
if (unlikely((bus > 255) || (devfn > 255) || (reg > 4095))) {
+err: *value = -1;
return -EINVAL;
}
rcu_read_lock();
What is the purpose of the rcu lock other than the old implementation had it?
addr = pci_dev_base(seg, bus, devfn);
The .map_bus op provides the same function if you restructure to use the generic accessors.
if (!addr) {
rcu_read_unlock();
goto err;
}
*value = pci_mmio_read(len, addr + reg);
rcu_read_unlock();
return 0;
+}
+int pci_mmcfg_write(unsigned int seg, unsigned int bus,
unsigned int devfn, int reg, int len, u32 value)
+{
char __iomem *addr;
/* Why do we have this when nobody checks it. How about a BUG()!? -AK */
if (unlikely((bus > 255) || (devfn > 255) || (reg > 4095)))
return -EINVAL;
rcu_read_lock();
addr = pci_dev_base(seg, bus, devfn);
if (!addr) {
rcu_read_unlock();
return -EINVAL;
}
pci_mmio_write(len, addr + reg, value);
rcu_read_unlock();
return 0;
+}
+static void __iomem *mcfg_ioremap(struct pci_mmcfg_region *cfg) +{
void __iomem *addr;
u64 start, size;
int num_buses;
start = cfg->address + PCI_MMCFG_BUS_OFFSET(cfg->start_bus);
num_buses = cfg->end_bus - cfg->start_bus + 1;
size = PCI_MMCFG_BUS_OFFSET(num_buses);
addr = ioremap_nocache(start, size);
if (addr)
addr -= PCI_MMCFG_BUS_OFFSET(cfg->start_bus);
return addr;
+}
+int __init pci_mmcfg_arch_init(void)
Where would this be called for the case of the generic host and using DT?
Rob