Re: [PATCH v5 03/12] PCI: brcmstb: Use common error handling code in brcm_pcie_probe()

[James Quinlan <james.quinlan@broadcom.com>]

On 8/13/24 12:45, Stanimir Varbanov wrote:
> Hi Jim,
>
> On 8/1/24 01:28, Jim Quinlan wrote:
>> o Move the clk_prepare_enable() below the resource allocations.
>> o Move the clk_prepare_enable() out of __brcm_pcie_remove() but
>>    add it to the end of brcm_pcie_remove().
>> o Add a jump target (clk_disable_unprepare) so that a bit of exception
>>    handling can be better reused at the end of this function implementation.
>> o Use dev_err_probe() where it makes sense.PASSWORD
> Those dev_err_probe produce these errors on RPi5:

Hi Stan,

Sorry, I clearly  missed that.  My perception of the dev_err_probe() 
semantics were incorrect -- I thought it didn't print anything at all  
if the "ret" param was zero, which would allow it to be used as an "if" 
conditional, as I am doing. Obviously not the case.

Will fix.

BTW I do not yet possess a CM5 so my testing is done on a CM4, 7712, and 
other STB chips.

Regards and thanks,

Jim Quinlan

Broadcom STB/CM

>
> rpi5:~ # dmesg -l err
> [    1.004960] brcm-pcie 1000110000.pcie: error 0000000000000000: could
> not assert reset 'swinit'
> [    1.013812] brcm-pcie 1000110000.pcie: error 0000000000000000: could
> not de-assert reset 'swinit' after asserting
> [    1.024222] brcm-pcie 1000110000.pcie: error 0000000000000000: failed
> to deassert 'rescal'
> [    1.533839] brcm-pcie 1000110000.pcie: link down
> [    1.627564] brcm-pcie 1000120000.pcie: error 0000000000000000: could
> not assert reset 'swinit'
> [    1.636415] brcm-pcie 1000120000.pcie: error 0000000000000000: could
> not de-assert reset 'swinit' after asserting
> [    1.646829] brcm-pcie 1000120000.pcie: error 0000000000000000: failed
> to deassert 'rescal'
>
> ... as you can see there is no error at all.
>
> ~Stan
>
>> Signed-off-by: Jim Quinlan <james.quinlan@broadcom.com>
>> ---
>>   drivers/pci/controller/pcie-brcmstb.c | 34 ++++++++++++---------------
>>   1 file changed, 15 insertions(+), 19 deletions(-)
>>
>> diff --git a/drivers/pci/controller/pcie-brcmstb.c b/drivers/pci/controller/pcie-brcmstb.c
>> index c08683febdd4..7595e7009192 100644
>> --- a/drivers/pci/controller/pcie-brcmstb.c
>> +++ b/drivers/pci/controller/pcie-brcmstb.c
>> @@ -1473,7 +1473,6 @@ static void __brcm_pcie_remove(struct brcm_pcie *pcie)
>>   		dev_err(pcie->dev, "Could not stop phy\n");
>>   	if (reset_control_rearm(pcie->rescal))
>>   		dev_err(pcie->dev, "Could not rearm rescal reset\n");
>> -	clk_disable_unprepare(pcie->clk);
>>   }
>>   
>>   static void brcm_pcie_remove(struct platform_device *pdev)
>> @@ -1484,6 +1483,7 @@ static void brcm_pcie_remove(struct platform_device *pdev)
>>   	pci_stop_root_bus(bridge->bus);
>>   	pci_remove_root_bus(bridge->bus);
>>   	__brcm_pcie_remove(pcie);
>> +	clk_disable_unprepare(pcie->clk);
>>   }
>>   
>>   static const int pcie_offsets[] = {
>> @@ -1613,31 +1613,26 @@ static int brcm_pcie_probe(struct platform_device *pdev)
>>   
>>   	pcie->ssc = of_property_read_bool(np, "brcm,enable-ssc");
>>   
>> -	ret = clk_prepare_enable(pcie->clk);
>> -	if (ret) {
>> -		dev_err(&pdev->dev, "could not enable clock\n");
>> -		return ret;
>> -	}
>>   	pcie->rescal = devm_reset_control_get_optional_shared(&pdev->dev, "rescal");
>> -	if (IS_ERR(pcie->rescal)) {
>> -		clk_disable_unprepare(pcie->clk);
>> +	if (IS_ERR(pcie->rescal))
>>   		return PTR_ERR(pcie->rescal);
>> -	}
>> +
>>   	pcie->perst_reset = devm_reset_control_get_optional_exclusive(&pdev->dev, "perst");
>> -	if (IS_ERR(pcie->perst_reset)) {
>> -		clk_disable_unprepare(pcie->clk);
>> +	if (IS_ERR(pcie->perst_reset))
>>   		return PTR_ERR(pcie->perst_reset);
>> -	}
>>   
>> -	ret = reset_control_reset(pcie->rescal);
>> +	ret = clk_prepare_enable(pcie->clk);
>>   	if (ret)
>> -		dev_err(&pdev->dev, "failed to deassert 'rescal'\n");
>> +		return dev_err_probe(&pdev->dev, ret, "could not enable clock\n");
>> +
>> +	ret = reset_control_reset(pcie->rescal);
>> +	if (dev_err_probe(&pdev->dev, ret, "failed to deassert 'rescal'\n"))
>> +		goto clk_disable_unprepare;
>>   
>>   	ret = brcm_phy_start(pcie);
>>   	if (ret) {
>>   		reset_control_rearm(pcie->rescal);
>> -		clk_disable_unprepare(pcie->clk);
>> -		return ret;
>> +		goto clk_disable_unprepare;
>>   	}
>>   
>>   	ret = brcm_pcie_setup(pcie);
>> @@ -1654,10 +1649,8 @@ static int brcm_pcie_probe(struct platform_device *pdev)
>>   	msi_np = of_parse_phandle(pcie->np, "msi-parent", 0);
>>   	if (pci_msi_enabled() && msi_np == pcie->np) {
>>   		ret = brcm_pcie_enable_msi(pcie);
>> -		if (ret) {
>> -			dev_err(pcie->dev, "probe of internal MSI failed");
>> +		if (dev_err_probe(pcie->dev, ret, "probe of internal MSI failed"))
>>   			goto fail;
>> -		}
>>   	}
>>   
>>   	bridge->ops = pcie->type == BCM7425 ? &brcm7425_pcie_ops : &brcm_pcie_ops;
>> @@ -1678,6 +1671,9 @@ static int brcm_pcie_probe(struct platform_device *pdev)
>>   
>>   fail:
>>   	__brcm_pcie_remove(pcie);
>> +clk_disable_unprepare:
>> +	clk_disable_unprepare(pcie->clk);
>> +
>>   	return ret;
>>   }
>>