On this platform, different vendor data is used. That requires a
compile-time check as we access (1) a global boolean & (2) our local
vendor data. Both symbols are accessible only when
CONFIG_ACPI_SPCR_TABLE is enabled.

Factor the vendor data overriding to a separate function that is empty
when CONFIG_ACPI_SPCR_TABLE is not defined.

Suggested-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Théo Lebrun <theo.lebrun@bootlin.com>
---
 drivers/tty/serial/amba-pl011.c | 25 ++++++++++++++++++-------
 1 file changed, 18 insertions(+), 7 deletions(-)

diff --git a/drivers/tty/serial/amba-pl011.c b/drivers/tty/serial/amba-pl011.c
index 4185d6fd243b..e08a32eb0ed1 100644
--- a/drivers/tty/serial/amba-pl011.c
+++ b/drivers/tty/serial/amba-pl011.c
@@ -2874,6 +2874,22 @@ static int pl011_resume(struct device *dev)
 
 static SIMPLE_DEV_PM_OPS(pl011_dev_pm_ops, pl011_suspend, pl011_resume);
 
+#ifdef CONFIG_ACPI_SPCR_TABLE
+static void qpdf2400_erratum44_workaround(struct device *dev,
+					  struct uart_amba_port *uap)
+{
+	if (qdf2400_e44_present)
+		return;
+
+	dev_info(dev, "working around QDF2400 SoC erratum 44\n");
+	uap->vendor = &vendor_qdt_qdf2400_e44;
+}
+#else
+static void qpdf2400_erratum44_workaround(struct device *dev,
+					  struct uart_amba_port *uap)
+{ /* empty */ }
+#endif
+
 static int sbsa_uart_probe(struct platform_device *pdev)
 {
 	struct uart_amba_port *uap;
@@ -2909,13 +2925,8 @@ static int sbsa_uart_probe(struct platform_device *pdev)
 		return ret;
 	uap->port.irq	= ret;
 
-#ifdef CONFIG_ACPI_SPCR_TABLE
-	if (qdf2400_e44_present) {
-		dev_info(&pdev->dev, "working around QDF2400 SoC erratum 44\n");
-		uap->vendor = &vendor_qdt_qdf2400_e44;
-	} else
-#endif
-		uap->vendor = &vendor_sbsa;
+	uap->vendor = &vendor_sbsa;
+	qpdf2400_erratum44_workaround(&pdev->dev, uap);
 
 	uap->reg_offset	= uap->vendor->reg_offset;
 	uap->fifosize	= 32;

-- 
2.42.0

On Mon, 20 Nov 2023, Théo Lebrun wrote:

> On this platform, different vendor data is used. That requires a
> compile-time check as we access (1) a global boolean & (2) our local
> vendor data. Both symbols are accessible only when
> CONFIG_ACPI_SPCR_TABLE is enabled.
> 
> Factor the vendor data overriding to a separate function that is empty
> when CONFIG_ACPI_SPCR_TABLE is not defined.
> 
> Suggested-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
> Signed-off-by: Théo Lebrun <theo.lebrun@bootlin.com>
> ---
>  drivers/tty/serial/amba-pl011.c | 25 ++++++++++++++++++-------
>  1 file changed, 18 insertions(+), 7 deletions(-)
> 
> diff --git a/drivers/tty/serial/amba-pl011.c b/drivers/tty/serial/amba-pl011.c
> index 4185d6fd243b..e08a32eb0ed1 100644
> --- a/drivers/tty/serial/amba-pl011.c
> +++ b/drivers/tty/serial/amba-pl011.c
> @@ -2874,6 +2874,22 @@ static int pl011_resume(struct device *dev)
>  
>  static SIMPLE_DEV_PM_OPS(pl011_dev_pm_ops, pl011_suspend, pl011_resume);
>  
> +#ifdef CONFIG_ACPI_SPCR_TABLE
> +static void qpdf2400_erratum44_workaround(struct device *dev,
> +					  struct uart_amba_port *uap)
> +{
> +	if (qdf2400_e44_present)

This should be !qdf2400_e44_present.

-- 
 i.


> +		return;
> +
> +	dev_info(dev, "working around QDF2400 SoC erratum 44\n");
> +	uap->vendor = &vendor_qdt_qdf2400_e44;
> +}
> +#else
> +static void qpdf2400_erratum44_workaround(struct device *dev,
> +					  struct uart_amba_port *uap)
> +{ /* empty */ }
> +#endif
> +
>  static int sbsa_uart_probe(struct platform_device *pdev)
>  {
>  	struct uart_amba_port *uap;
> @@ -2909,13 +2925,8 @@ static int sbsa_uart_probe(struct platform_device *pdev)
>  		return ret;
>  	uap->port.irq	= ret;
>  
> -#ifdef CONFIG_ACPI_SPCR_TABLE
> -	if (qdf2400_e44_present) {
> -		dev_info(&pdev->dev, "working around QDF2400 SoC erratum 44\n");
> -		uap->vendor = &vendor_qdt_qdf2400_e44;
> -	} else
> -#endif
> -		uap->vendor = &vendor_sbsa;
> +	uap->vendor = &vendor_sbsa;
> +	qpdf2400_erratum44_workaround(&pdev->dev, uap);
>  
>  	uap->reg_offset	= uap->vendor->reg_offset;
>  	uap->fifosize	= 32;
> 
> 

Hello,

On Mon Nov 20, 2023 at 10:55 AM CET, Ilpo Järvinen wrote:
> On Mon, 20 Nov 2023, Théo Lebrun wrote:
>
> > On this platform, different vendor data is used. That requires a
> > compile-time check as we access (1) a global boolean & (2) our local
> > vendor data. Both symbols are accessible only when
> > CONFIG_ACPI_SPCR_TABLE is enabled.
> > 
> > Factor the vendor data overriding to a separate function that is empty
> > when CONFIG_ACPI_SPCR_TABLE is not defined.
> > 
> > Suggested-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
> > Signed-off-by: Théo Lebrun <theo.lebrun@bootlin.com>
> > ---
> >  drivers/tty/serial/amba-pl011.c | 25 ++++++++++++++++++-------
> >  1 file changed, 18 insertions(+), 7 deletions(-)
> > 
> > diff --git a/drivers/tty/serial/amba-pl011.c b/drivers/tty/serial/amba-pl011.c
> > index 4185d6fd243b..e08a32eb0ed1 100644
> > --- a/drivers/tty/serial/amba-pl011.c
> > +++ b/drivers/tty/serial/amba-pl011.c
> > @@ -2874,6 +2874,22 @@ static int pl011_resume(struct device *dev)
> >  
> >  static SIMPLE_DEV_PM_OPS(pl011_dev_pm_ops, pl011_suspend, pl011_resume);
> >  
> > +#ifdef CONFIG_ACPI_SPCR_TABLE
> > +static void qpdf2400_erratum44_workaround(struct device *dev,
> > +					  struct uart_amba_port *uap)
> > +{
> > +	if (qdf2400_e44_present)
>
> This should be !qdf2400_e44_present.

Completely right! I reversed the if-logic to see how it looked & I
forgot negating the condition when going back to the current shape.
I've got the fix ready for a v4. You've got some good eyes, thanks.

I'll wait a bit to see if there are any other review & avoid spamming
the maintainers.

Thanks,

--
Théo Lebrun, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com