On Thu, Nov 20, 2014 at 02:47:35AM +0000, Yijing Wang wrote:

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+static void pci_release_host_bridge_dev(struct device *dev)
+{
+       struct pci_host_bridge *bridge =3D to_pci_host_bridge(dev);
+
+       if (bridge->release_fn)
+               bridge->release_fn(bridge);
+       pci_free_resource_list(&bridge->windows);
+       kfree(bridge);
+}
+
+struct pci_host_bridge *pci_create_host_bridge(
+               struct device *parent, u32 db,
+               struct pci_ops *ops, void *sysdata,

I don't thinks it is worth moving the buses' pci_ops into pci_host_br=

idge. It

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might be more useful to have pci_host_bridge specific ops here.

Because we want to create pci_host_bridge before pci root bus creation=

,

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so when we scan the root bus and child buses, we use pci_host_bridge a=

s

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the only argument, and another pci_host_info will be addes in later pa=

tch,

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which one support carry the pci_host_bridge ops.

But pci_create_root_bus() already has a pci_ops argument, I don't see t=

he reason

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to drop that.

pci_create_host_bridge() can get pci_host_bridge ops while pci_create_r=

oot_bus() gets

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the bus ops. For find out the MSI controller, the domain number and any=

 other HB

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specific stuff, you use the HB ops. For config R/W acceses you use bus =

ops.

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=20
I want to unexport pci_create_root_bus() if we have pci_create_host_bridg=

e().

That's fine, but the function signature doesn't change, right? And I think =
we should keep
pci_scan_root_bus() with the current signature as well (except change sysda=
ta into a
struct pci_host_bridge *). We create the host bridge in one step, stuff it =
with all the
data that we need for scanning the root and associated busses, and then cal=
l pci_scan_root_bus().
pci_host_bridge has the ops from pci_create_host_bridge() and the root bus =
from pci_scan_root_bus().

Hope this makes sense.

=20
=20

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-struct pci_bus *pci_create_root_bus(struct device *parent, u32 db,
-               struct pci_ops *ops, void *sysdata, struct list_head=

 *resources)

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+struct pci_bus *__pci_create_root_bus(struct pci_host_bridge *bridg=

e)

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 {
        int error;
-       struct pci_host_bridge *bridge;
        struct pci_bus *b, *b2;
-       struct pci_host_bridge_window *window, *n;
+       struct pci_host_bridge_window *window;
        struct resource *res;
        resource_size_t offset;
        char bus_addr[64];
        char *fmt;
-       u8      bus =3D PCI_BUSNUM(db);
+       struct device *parent =3D bridge->dev.parent;

        b =3D pci_alloc_bus(NULL);
        if (!b)
                return NULL;

-       b->sysdata =3D sysdata;
-       b->ops =3D ops;
-       b->number =3D b->busn_res.start =3D bus;
+       b->sysdata =3D bridge->sysdata;

I think bridge should be the b->sysdata here.

? what's the meaning?

Currently, bus->sysdata holds a pointer to the arch/driver host bridge =

structure, as passed

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in pci_create_root_bus(). If you agree with my idea of wrapping the hos=

t bridge driver

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structure around the pci_host_bridge, then we will always have a way of=

 retrieving that

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information; but for backwards compatibility we could set bus->sysdata =

to be the bridge.

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Then existing macros that convert sysdata to pci_controller can be reus=

ed after being

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updated.

=20
I think wrapping the host bridge driver structure around the pci_host_bri=

dge could help

us to find the private pci_controller, but in this case, pci_host_bridge =

is not a pointer

so we put all pci_host_bridge init stuff in host drivers ?=20

Of course we put pci_host_bridge init *calls* in the host drivers because w=
e need to do host
driver specific initialisation there anyway.=20

And if we still use arch spec
macros convert ssydata to pci_controller, so what's the greatest advantag=

e ?

Agree, the macro is not useful unless we have a common pci_controller struc=
ture. Sorry about
the noise.

=20
If we move domain and msi_chip out of sysdata, what's other things in sys=

data still need us

to convert in PCI core ?

I've never said we need to keep sysdata. From my discussion with Bjorn a ye=
ar ago the idea was
to put the sysdata members into pci_host_bridge structure and remove sysdat=
a member from pci_bus.
pci_scan_root_bus() can still get a parameter called sysdata if we want, bu=
t it will be a
struct pci_host_bridge * type.

Best regards,
Liviu

=20
=20
=20

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Best regards,
Liviu

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+       b->ops =3D bridge->ops;

See comment above why I don't think this is necessary.

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+       b->number =3D b->busn_res.start =3D bridge->busnum;
        pci_bus_assign_domain_nr(b, parent);
-       b2 =3D pci_find_bus(pci_domain_nr(b), bus);
+       bridge->domain =3D pci_domain_nr(b);

Do you really want to overwrite the bridge's domain with the one from=

 a bus that

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could possibly be rejected a couple of lines further down?

As an asside: if we are doing the split of pci_host_bridge from root =

bus creation

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it is worth in my opinion to move the domain setup in pci_create_host=

_bridge()

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and stop fiddling with it here.

Hi Liviu, these lines just temporary, I will remove it after all host =

drivers

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save its domain in pci_host_bridge.

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Otherwise it looks to me like you are heading in the right direction.

Thanks!
Yijing.

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Best regards,
Liviu

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+       b2 =3D pci_find_bus(pci_domain_nr(b), bridge->busnum);
        if (b2) {
                /* If we already got to this bus through a different=

 bridge, ignore it */

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                dev_dbg(&b2->dev, "bus already known\n");
                goto err_out;
        }

-       bridge =3D pci_alloc_host_bridge(b);
-       if (!bridge)
-               goto err_out;
-
-       bridge->dev.parent =3D parent;
-       bridge->dev.release =3D pci_release_host_bridge_dev;
-       dev_set_name(&bridge->dev, "pci%04x:%02x", pci_domain_nr(b),=

 bus);

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-       error =3D pcibios_root_bridge_prepare(bridge);
-       if (error) {
-               kfree(bridge);
-               goto err_out;
-       }
-
-       error =3D device_register(&bridge->dev);
-       if (error) {
-               put_device(&bridge->dev);
-               goto err_out;
-       }
        b->bridge =3D get_device(&bridge->dev);
        device_enable_async_suspend(b->bridge);
        pci_set_bus_of_node(b);

@@ -1950,7 +1899,7 @@ struct pci_bus *pci_create_root_bus(struct dev=

ice *parent, u32 db,

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        b->dev.class =3D &pcibus_class;
        b->dev.parent =3D b->bridge;
-       dev_set_name(&b->dev, "%04x:%02x", pci_domain_nr(b), bus);
+       dev_set_name(&b->dev, "%04x:%02x", pci_domain_nr(b), b->numb=

er);

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        error =3D device_register(&b->dev);
        if (error)
                goto class_dev_reg_err;

@@ -1966,12 +1915,11 @@ struct pci_bus *pci_create_root_bus(struct d=

evice *parent, u32 db,

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                printk(KERN_INFO "PCI host bridge to bus %s\n", dev_=

name(&b->dev));

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        /* Add initial resources to the bus */
-       list_for_each_entry_safe(window, n, resources, list) {
-               list_move_tail(&window->list, &bridge->windows);
+       list_for_each_entry(window, &bridge->windows, list) {
                res =3D window->res;
                offset =3D window->offset;
                if (res->flags & IORESOURCE_BUS)
-                       pci_bus_insert_busn_res(b, bus, res->end);
+                       pci_bus_insert_busn_res(b, b->number, res->e=

nd);

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                else
                        pci_bus_add_resource(b, res, 0);
                if (offset) {

@@ -2001,6 +1949,25 @@ err_out:
        return NULL;
 }

+struct pci_bus *pci_create_root_bus(struct device *parent, u32 bus,
+               struct pci_ops *ops, void *sysdata, struct list_head=

 *resources)

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+{
+       struct pci_host_bridge *host;
+
+       host =3D pci_create_host_bridge(parent, bus, ops,
+                       sysdata ,resources);
+       if (!host)
+               return NULL;
+
+       host->bus =3D __pci_create_root_bus(host);
+       if (!host->bus) {
+               pci_free_host_bridge(host);
+               return NULL;
+       }
+
+       return host->bus;
+}
+
 int pci_bus_insert_busn_res(struct pci_bus *b, int bus, int bus_max=

)

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 {
        struct resource *res =3D &b->busn_res;

@@ -2069,40 +2036,37 @@ struct pci_bus *pci_scan_root_bus(struct dev=

ice *parent, u32 db,

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 {
        struct pci_host_bridge_window *window;
        bool found =3D false;
-       struct pci_bus *b;
-       LIST_HEAD(default_res);
+       struct pci_host_bridge *host;
        int max;

-       if (!resources) {
-               pci_add_resource(&default_res, &ioport_resource);
-               pci_add_resource(&default_res, &iomem_resource);
-               pci_add_resource(&default_res, &busn_resource);
-       } else {
-               list_for_each_entry(window, resources, list)
-                       if (window->res->flags & IORESOURCE_BUS) {
-                               found =3D true;
-                               break;
-                       }
-       }
+       host =3D pci_create_host_bridge(parent, db, ops, sysdata, re=

sources);

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+       if (!host)
+               return NULL;

-       b =3D pci_create_root_bus(parent, db, ops, sysdata,
-                       resources ? resources : &default_res);
-       if (!b)
+       list_for_each_entry(window, &host->windows, list)
+               if (window->res->flags & IORESOURCE_BUS) {
+                       found =3D true;
+                       break;
+               }
+
+       host->bus =3D __pci_create_root_bus(host);
+       if (!host->bus) {
+               pci_free_host_bridge(host);
                return NULL;
+       }

        if (!found) {
-               dev_info(&b->dev,
+               dev_info(&host->bus->dev,
                 "No busn resource found for root bus, will use [bus=

 %02x-ff]\n",

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                        PCI_BUSNUM(db));
-               pci_bus_insert_busn_res(b, PCI_BUSNUM(db), 255);
+               pci_bus_insert_busn_res(host->bus, PCI_BUSNUM(db), 2=

55);

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        }

-       max =3D pci_scan_child_bus(b);
-
+       max =3D pci_scan_child_bus(host->bus);
        if (!found)
-               pci_bus_update_busn_res_end(b, max);
+               pci_bus_update_busn_res_end(host->bus, max);

-       return b;
+       return host->bus;
 }
 EXPORT_SYMBOL(pci_scan_root_bus);

diff --git a/include/linux/pci.h b/include/linux/pci.h
index 8b11b38..daa7f40 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h

@@ -402,7 +402,12 @@ struct pci_host_bridge_window {
 struct pci_host_bridge {
        struct device dev;
        struct pci_bus *bus;            /* root bus */
+       struct list_head list;
        struct list_head windows;       /* pci_host_bridge_windows *=

/

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+       int busnum;
+       int domain;
+       void *sysdata;
+       struct pci_ops *ops;
        void (*release_fn)(struct pci_host_bridge *);
        void *release_data;
 };

@@ -413,7 +418,9 @@ void pci_set_host_bridge_release(struct pci_host=

_bridge *bridge,

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                     void *release_data);

 int pcibios_root_bridge_prepare(struct pci_host_bridge *bridge);
-
+struct pci_host_bridge *pci_create_host_bridge(
+               struct device *parent, u32 db, struct pci_ops *ops,
+               void *sys, struct list_head *resources);
 /*
  * The first PCI_BRIDGE_RESOURCE_NUM PCI bus resources (those that =

correspond

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  * to P2P or CardBus bridge windows) go in a table.  Additional one=

s (for

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@@ -770,6 +777,8 @@ void pci_bus_add_devices(const struct pci_bus *b=

us);

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 struct pci_bus *pci_create_root_bus(struct device *parent, u32 bus,
                                    struct pci_ops *ops, void *sysda=

ta,

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                                    struct list_head *resources);
+struct pci_bus *__pci_create_root_bus(struct pci_host_bridge *host)=

;

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+void pci_free_host_bridge(struct pci_host_bridge *host);
 int pci_bus_insert_busn_res(struct pci_bus *b, int bus, int busmax)=

;

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 int pci_bus_update_busn_res_end(struct pci_bus *b, int busmax);
 void pci_bus_release_busn_res(struct pci_bus *b);
--
1.7.1

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To unsubscribe from this list: send the line "unsubscribe linux-pci"=

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the body of a message to majordomo@vger.kernel.org
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--
Thanks!
Yijing

--
To unsubscribe from this list: send the line "unsubscribe linux-pci" i=

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=20
=20
--
Thanks!
Yijing
=20
=20

--=20
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
| I would like to |
| fix the world,  |
| but they're not |
| giving me the   |
 \ source code!  /
  ---------------
    =C2=AF\_(=E3=83=84)_/=C2=AF