'assigned-addresses' is used for certain PCI device type nodes in
lieu of 'reg', since this is enforced by of/address.c, have
of_device_make_bus_id look there as well.
Signed-off-by: Jason Gunthorpe <[email protected]>
---
drivers/of/platform.c | 2 ++
1 files changed, 2 insertions(+), 0 deletions(-)
of_can_translate_address and of_translate_address already support
using assigned-addresses.
diff --git a/drivers/of/platform.c b/drivers/of/platform.c
index b80891b..4f0f701 100644
--- a/drivers/of/platform.c
+++ b/drivers/of/platform.c
@@ -105,6 +105,8 @@ void of_device_make_bus_id(struct device *dev)
* For MMIO, get the physical address
*/
reg = of_get_property(node, "reg", NULL);
+ if (!reg)
+ reg = of_get_property(node, "assigned-addresses", NULL);
if (reg) {
if (of_can_translate_address(node)) {
addr = of_translate_address(node, reg);
--
1.7.5.4
On Wed, 21 Nov 2012 14:02:40 -0700, Jason Gunthorpe <[email protected]> wrote:
> 'assigned-addresses' is used for certain PCI device type nodes in
> lieu of 'reg', since this is enforced by of/address.c, have
> of_device_make_bus_id look there as well.
>
> Signed-off-by: Jason Gunthorpe <[email protected]>
If it is a PCI device, then of_device_make_bus_id() shouldn't come into
play. PCI devices already have their own naming scheme. Only
platform_bus device creation uses of_device_make_bus_id(). What am I
missing?
g.
> ---
> drivers/of/platform.c | 2 ++
> 1 files changed, 2 insertions(+), 0 deletions(-)
>
> of_can_translate_address and of_translate_address already support
> using assigned-addresses.
>
> diff --git a/drivers/of/platform.c b/drivers/of/platform.c
> index b80891b..4f0f701 100644
> --- a/drivers/of/platform.c
> +++ b/drivers/of/platform.c
> @@ -105,6 +105,8 @@ void of_device_make_bus_id(struct device *dev)
> * For MMIO, get the physical address
> */
> reg = of_get_property(node, "reg", NULL);
> + if (!reg)
> + reg = of_get_property(node, "assigned-addresses", NULL);
> if (reg) {
> if (of_can_translate_address(node)) {
> addr = of_translate_address(node, reg);
> --
> 1.7.5.4
>
--
Grant Likely, B.Sc, P.Eng.
Secret Lab Technologies, Ltd.
On Mon, Nov 26, 2012 at 02:03:16PM +0000, Grant Likely wrote:
> On Wed, 21 Nov 2012 14:02:40 -0700, Jason Gunthorpe <[email protected]> wrote:
> > 'assigned-addresses' is used for certain PCI device type nodes in
> > lieu of 'reg', since this is enforced by of/address.c, have
> > of_device_make_bus_id look there as well.
> >
> > Signed-off-by: Jason Gunthorpe <[email protected]>
>
> If it is a PCI device, then of_device_make_bus_id() shouldn't come into
> play. PCI devices already have their own naming scheme. Only
> platform_bus device creation uses of_device_make_bus_id(). What am I
> missing?
In my embedded case I have a complex PCI-E connected SOC device.
This is modeled in OF by having a PCI-E bus, a PCI-E device node, and
then all of the SOC devices (I2C, GPIO, drivers, etc) placed under the
PCI-E device node.
The PCI driver that matches the device just turns it on and calls
of_platform_populate(..) with its own node as an argument.
So of_device_make_bus_id isn't called on a PCI-E device node, it is
called on the platform_device children of that node, and due to the
way the other code works, and what the OF rules seem to be, those
childen all use assigned-addresses. Without this patch the code just
assigns monotonic ids to those nodes.
Jason
On Mon, 26 Nov 2012 11:20:54 -0700, Jason Gunthorpe <[email protected]> wrote:
> On Mon, Nov 26, 2012 at 02:03:16PM +0000, Grant Likely wrote:
> > On Wed, 21 Nov 2012 14:02:40 -0700, Jason Gunthorpe <[email protected]> wrote:
> > > 'assigned-addresses' is used for certain PCI device type nodes in
> > > lieu of 'reg', since this is enforced by of/address.c, have
> > > of_device_make_bus_id look there as well.
> > >
> > > Signed-off-by: Jason Gunthorpe <[email protected]>
> >
> > If it is a PCI device, then of_device_make_bus_id() shouldn't come into
> > play. PCI devices already have their own naming scheme. Only
> > platform_bus device creation uses of_device_make_bus_id(). What am I
> > missing?
>
> In my embedded case I have a complex PCI-E connected SOC device.
>
> This is modeled in OF by having a PCI-E bus, a PCI-E device node, and
> then all of the SOC devices (I2C, GPIO, drivers, etc) placed under the
> PCI-E device node.
>
> The PCI driver that matches the device just turns it on and calls
> of_platform_populate(..) with its own node as an argument.
>
> So of_device_make_bus_id isn't called on a PCI-E device node, it is
> called on the platform_device children of that node, and due to the
> way the other code works, and what the OF rules seem to be, those
> childen all use assigned-addresses. Without this patch the code just
> assigns monotonic ids to those nodes.
Hmmm. okay that makes sense, but something still isn't quite right. So
of_translate_address should take care of drilling down through the bus
layers, and when it gets to the PCI node it /should/ use
of_bus_pci_translate to handle traversing down to the parent node (which
uses the 'assigned-addresses' for the pci node.
However, in your case, of_device_make_bus_id() isn't using that code
path and you're getting a generic name instead (with no relation to the
device address). Correct?
If that is the case, then the solution is to figure out why
of_translate_address() doesn't currently handle your situation and fix
it. It is not a good idea to add assigned-addresses specific parsing
code to that function since that won't work for any of the other bus
types.
g.
On Thu, Nov 29, 2012 at 04:26:48PM +0000, Grant Likely wrote:
> Hmmm. okay that makes sense, but something still isn't quite right. So
> of_translate_address should take care of drilling down through the bus
> layers, and when it gets to the PCI node it /should/ use
> of_bus_pci_translate to handle traversing down to the parent node (which
> uses the 'assigned-addresses' for the pci node.
The address translation machinery requires PCI format addresses (ie
address-cells=3) for all nodes below a PCI bus. Part of this
requirement is that 'assigned-addresses' is used for resources, *not*
'reg'.
If you attempt to stick a 'reg' in a block nested below a
'device_type="pci"' the kernel throws lots of error messsages and
generates bad address mappings.
So, we are required to use'assigned-addresses' with the 5 word format
instead of reg. This seems to be a spec requirement for everything
below a PCI bus.
We end up with a DTS where the PCI bus and everything below it must
be described in the 5 word format that looks like this:
pex@e0000000 { // <-- This is the PCI bus/controller node
device_type = "pci";
ranges = <0x02000000 0x00000000 0x00000000 0xe0000000 0x0 0x8000000>;
soc@0 { // <-- This is the actual PCI device
ranges = <0x02000000 0x00000000 0x00000000 0x02000000 0x00000000 0x00000000 0x0 0x8000000>;
gpio3: gpio@8 { // <-- This is a platform device
#gpio-cells = <2>;
compatible = "linux,basic-mmio-gpio";
gpio-controller;
reg-names = "dat", "set", "dirin";
assigned-addresses = <0x02000000 0x0 0x8 0x0 4>,
<0x02000000 0x0 0xc 0x0 4>,
<0x02000000 0x0 0x10 0x0 4>;
};
Which (when combined with the platform_device_add change) builds up an
iomem like:
e0000000-e7ffffff : PCIe 0 MEM
e0000000-e000ffff : 0000:00:01.0
e0000000-e0000fff : /pex@e0000000/soc@0/control@0
e0000008-e000000b : dat
e0000008-e000000b : dat
e000000c-e000000f : set
e000000c-e000000f : set
e0000010-e0000013 : dirin
e0000010-e0000013 : dirin
(I trimmed control@0 node from the dts fragment, see other mails on
the overlapping regions)
And a sysfs like this:
/sys/devices/pci0000:00/0000:00:01.0/e0000000.control
/sys/devices/pci0000:00/0000:00:01.0/e0000008.gpio
Without the patch the sysfs names will not have the address (gpio.0 or
whatever it is), but all other address calculations work correctly.
> However, in your case, of_device_make_bus_id() isn't using that code
> path and you're getting a generic name instead (with no relation to the
> device address). Correct?
Right.
> If that is the case, then the solution is to figure out why
> of_translate_address() doesn't currently handle your situation and
> fix
of_translate_address works perfectly - resource records are
constructed correctly, for instance. The issue is that
of_device_make_bus_id() doesn't call it:
@@ -105,6 +105,8 @@ void of_device_make_bus_id(struct device *dev)
* For MMIO, get the physical address
*/
reg = of_get_property(node, "reg", NULL);
+ if (!reg)
+ reg = of_get_property(node, "assigned-addresses", NULL);
if (reg) {
if (of_can_translate_address(node)) {
addr = of_translate_address(node, reg);
ie what is happening is that of_device_make_bus_id *only* calls
*_translate_address if 'reg' is a property of the node. The patch
simply extends that to call if 'reg' or 'assigned-addresses' are a
property of the node. of_device_make_bus_id doesn't do anything with
the 'reg' variable other than test it against NULL.
Jason
On Thu, 29 Nov 2012 12:38:29 -0700, Jason Gunthorpe <[email protected]> wrote:
> On Thu, Nov 29, 2012 at 04:26:48PM +0000, Grant Likely wrote:
>
> > Hmmm. okay that makes sense, but something still isn't quite right. So
> > of_translate_address should take care of drilling down through the bus
> > layers, and when it gets to the PCI node it /should/ use
> > of_bus_pci_translate to handle traversing down to the parent node (which
> > uses the 'assigned-addresses' for the pci node.
>
> The address translation machinery requires PCI format addresses (ie
> address-cells=3) for all nodes below a PCI bus. Part of this
> requirement is that 'assigned-addresses' is used for resources, *not*
> 'reg'.
>
> If you attempt to stick a 'reg' in a block nested below a
> 'device_type="pci"' the kernel throws lots of error messsages and
> generates bad address mappings.
Have you added the appropriate #address-cells and #size-cells to the pci
device node to go back to a non-pci addressing mode? assigned-addresses
only makes sense in the pci-device node itself. reg should work for all
nodes below that, and if it doesn't then it is a bug that we need to
fix.
g.
On Fri, Nov 30, 2012 at 09:48:05AM +0000, Grant Likely wrote:
> > If you attempt to stick a 'reg' in a block nested below a
> > 'device_type="pci"' the kernel throws lots of error messsages and
> > generates bad address mappings.
>
> Have you added the appropriate #address-cells and #size-cells to the pci
> device node to go back to a non-pci addressing mode?
> assigned-addresses
Switching away from the 5 dword address format is not ideal
because then there is no way to specify the resource region (prefetch,
io, mmio) and mmio would have to be assumed.
> only makes sense in the pci-device node itself. reg should work for all
> nodes below that, and if it doesn't then it is a bug that we need to
> fix.
Okay.. but how should the DTS be constructed?
pcie_bus { // The PCI-E bus
device_type = "pci";
ranges = <5dw ranges>;
#address-cells = <3>;
#size-cells = <2>;
soc_bridge { // The PCI-E device
device_type = "pci";
ranges = <5dw ranges>;
soc_device { // Internal device
assigned-address = <5dw regs>
};
};
};
This is what I have now, the soc_bridge PCI-E device is DTS modeled as
a PCI bridge - it has a ranges with its memory location, and the
children nodes are relative to those ranges. This would not be typical
for a non-bridge PCI-E device.
The reason for the 'assigned-address' requirement with the current
kernel code is the device_type=pci on soc_bridge. This makes
of_match_bus(parent) for soc_device return the PCI structure, which
has '.addresses = "assigned-addresses",'
So.. how would you like this to look?
Jason