All of lore.kernel.org
 help / color / mirror / Atom feed
From: Stefan Roese <sr@denx.de>
To: "Pali Rohár" <pali@kernel.org>
Cc: linux-pci@vger.kernel.org,
	Bharat Kumar Gogada <bharat.kumar.gogada@xilinx.com>,
	Bjorn Helgaas <helgaas@kernel.org>,
	Michal Simek <michal.simek@xilinx.com>
Subject: Re: [PATCH v4 2/2] PCI: xilinx-nwl: Add method to init_platform_service_irqs hook
Date: Fri, 14 Jan 2022 18:03:03 +0100	[thread overview]
Message-ID: <a230328e-e08c-28c9-e95a-10daafa8331b@denx.de> (raw)
In-Reply-To: <20220114123446.f2boleizo4yex7ow@pali>

On 1/14/22 13:34, Pali Rohár wrote:
> On Friday 14 January 2022 13:13:16 Stefan Roese wrote:
>> On 1/14/22 12:48, Pali Rohár wrote:
>>> On Friday 14 January 2022 08:58:34 Stefan Roese wrote:
>>>> From: Bharat Kumar Gogada <bharat.kumar.gogada@xilinx.com>
>>>>
>>>> Add nwl_init_platform_service_irqs() hook to init_platform_service_irqs
>>>> to register the platform-specific Service Errors IRQs for this PCIe
>>>> controller to fully support e.g. AER on this platform.
>>>>
>>>> Signed-off-by: Bharat Kumar Gogada <bharat.kumar.gogada@xilinx.com>
>>>> Signed-off-by: Stefan Roese <sr@denx.de>
>>>> Cc: Bjorn Helgaas <helgaas@kernel.org>
>>>> Cc: Pali Rohár <pali@kernel.org>
>>>> Cc: Michal Simek <michal.simek@xilinx.com>
>>>
>>> Reviewed-by: Pali Rohár <pali@kernel.org>
>>>
>>>> ---
>>>>    drivers/pci/controller/pcie-xilinx-nwl.c | 18 ++++++++++++++++++
>>>>    1 file changed, 18 insertions(+)
>>>>
>>>> diff --git a/drivers/pci/controller/pcie-xilinx-nwl.c b/drivers/pci/controller/pcie-xilinx-nwl.c
>>>> index 414b679175b3..540536bbe3f8 100644
>>>> --- a/drivers/pci/controller/pcie-xilinx-nwl.c
>>>> +++ b/drivers/pci/controller/pcie-xilinx-nwl.c
>>>> @@ -24,6 +24,7 @@
>>>>    #include <linux/irqchip/chained_irq.h>
>>>>    #include "../pci.h"
>>>> +#include "../pcie/portdrv.h"
>>>>    /* Bridge core config registers */
>>>>    #define BRCFG_PCIE_RX0			0x00000000
>>>> @@ -806,6 +807,22 @@ static int nwl_pcie_parse_dt(struct nwl_pcie *pcie,
>>>>    	return 0;
>>>>    }
>>>> +static int nwl_init_platform_service_irqs(struct pci_dev *dev, int *irqs,
>>>> +					  int plat_mask)
>>>> +{
>>>> +	struct pci_host_bridge *bridge;
>>>> +	struct nwl_pcie *pcie;
>>>> +
>>>> +	bridge = pci_find_host_bridge(dev->bus);
>>>> +	pcie = pci_host_bridge_priv(bridge);
>>>> +	if (plat_mask & PCIE_PORT_SERVICE_AER) {
>>>> +		irqs[PCIE_PORT_SERVICE_AER_SHIFT] = pcie->irq_misc;
>>>> +		return 0; /* platform-specific service IRQ installed */
>>>> +	}
>>>
>>> Just I want to be sure, with this change PME and HP interrupts are not
>>> provided even when plat_mask argument contains them.
>>
>> This function is only used for Root Ports.
> 
> Technically, also Root Ports can support hot plugging. But that it
> probably not the case of your board if it has PCIe switch connected to
> the Root Port which is not removable.
> 
> But hot plug interrupt can be optionally used also for signalling change
> of Data Link Layer state. And this information can be useful also in
> Root Port if to it is connected non-removable device.
> 
> So if init_platform_service_irqs callback explicitly do not specify PME
> or HP interrupts for the Root Port then kernel would not load pme or
> pciehp service for the Root Port.
> 
> This is note for me, that when I will go to use this callback in other
> drivers, I need to check that I provide interrupts for all supported
> services...

It might very well be the case, that this current implementation does
not fully handle all use-cases (controller specific). The code can be
extended and/or fixed, once other users will show up.

Thanks,
Stefan

>> E.g. HP at the downstream
>> ports of the PCIe switch still works in our case, as here
>> pcie_init_service_irqs() still gets called:
>>
>> # cat /proc/interrupts | grep pci
>>   44:          0          0          0          0     GICv2 150 Level
>> nwl_pcie:misc, aerdrv
>>   61:          2          0          0          0  nwl_pcie:msi 1064960 Edge
>> pciehp
>>   63:          0          0          0          0  nwl_pcie:msi 1081344 Edge
>> pciehp
>>   65:          4          0          0          0  nwl_pcie:msi 1097728 Edge
>> pciehp
> 
> Yes, as PCIe switch is different device it should work fine.
> 
>> Thanks,
>> Stefan
>>
>>>> +
>>>> +	return -ENODEV; /* platform-specific service IRQ not installed */
>>>> +}
>>>> +
>>>>    static const struct of_device_id nwl_pcie_of_match[] = {
>>>>    	{ .compatible = "xlnx,nwl-pcie-2.11", },
>>>>    	{}
>>>> @@ -857,6 +874,7 @@ static int nwl_pcie_probe(struct platform_device *pdev)
>>>>    	bridge->sysdata = pcie;
>>>>    	bridge->ops = &nwl_pcie_ops;
>>>> +	bridge->init_platform_service_irqs = nwl_init_platform_service_irqs;
>>>>    	if (IS_ENABLED(CONFIG_PCI_MSI)) {
>>>>    		err = nwl_pcie_enable_msi(pcie);
>>>> -- 
>>>> 2.34.1
>>>>
>>
>> Viele Grüße,
>> Stefan Roese
>>
>> -- 
>> DENX Software Engineering GmbH,      Managing Director: Wolfgang Denk
>> HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
>> Phone: (+49)-8142-66989-51 Fax: (+49)-8142-66989-80 Email: sr@denx.de

Viele Grüße,
Stefan Roese

-- 
DENX Software Engineering GmbH,      Managing Director: Wolfgang Denk
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: (+49)-8142-66989-51 Fax: (+49)-8142-66989-80 Email: sr@denx.de

  reply	other threads:[~2022-01-14 17:03 UTC|newest]

Thread overview: 20+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-01-14  7:58 [PATCH v4 0/2] Add support to register platform service IRQ Stefan Roese
2022-01-14  7:58 ` [PATCH v4 1/2] PCI/portdrv: Add option to setup IRQs for platform-specific Service Errors Stefan Roese
2022-01-14 11:46   ` Pali Rohár
2022-05-28  0:09   ` Bjorn Helgaas
2022-05-30  8:18     ` Stefan Roese
2022-05-30  8:32       ` Pali Rohár
2022-05-31 21:31         ` Bjorn Helgaas
2022-05-31 22:57           ` Pali Rohár
2022-06-01 11:47           ` Stefan Roese
2022-06-01 11:53             ` Pali Rohár
2022-06-08 18:39             ` Bjorn Helgaas
2022-01-14  7:58 ` [PATCH v4 2/2] PCI: xilinx-nwl: Add method to init_platform_service_irqs hook Stefan Roese
2022-01-14 11:48   ` Pali Rohár
2022-01-14 12:13     ` Stefan Roese
2022-01-14 12:34       ` Pali Rohár
2022-01-14 17:03         ` Stefan Roese [this message]
2022-03-24 16:52 ` [PATCH v4 0/2] Add support to register platform service IRQ Stefan Roese
2022-03-31 15:30   ` Bjorn Helgaas
2022-04-01  6:28     ` Stefan Roese
2022-04-01 12:35       ` Bjorn Helgaas

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=a230328e-e08c-28c9-e95a-10daafa8331b@denx.de \
    --to=sr@denx.de \
    --cc=bharat.kumar.gogada@xilinx.com \
    --cc=helgaas@kernel.org \
    --cc=linux-pci@vger.kernel.org \
    --cc=michal.simek@xilinx.com \
    --cc=pali@kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.