[PATCH v3] mmc: sunxi: remove output of virtual base address

[PATCH v3] mmc: sunxi: remove output of virtual base address

[Andre Przywara]

Recent Linux versions refuse to print actual virtual kernel addresses,
to not give a hint about the location of the kernel in a randomized virtual
address space. This affects the output of the sunxi MMC controller
driver, which now produces the rather uninformative line:

[    1.482660] sunxi-mmc 1c0f000.mmc: base:0x(____ptrval____) irq:8

Since the virtual base address is not really interesting in the first
place, let's just drop this value. The same applies to Linux' notion of
the interrupt number, which is independent from the GIC SPI number.
We have the physical address as part of the DT node name, which is way
more useful for debugging purposes.
To keep a success message in the driver, we make this purpose explicit
with the word "initialized", plus print some information that is not too
obvious and that we learned while probing the device:
the maximum request size and whether it uses the new timing mode.
So the output turns into:
[    1.750626] sunxi-mmc 1c0f000.mmc: initialized, max. request size: 16384 KB, uses new timings mode
[    1.786699] sunxi-mmc 1c11000.mmc: initialized, max. request size: 2048 KB

Signed-off-by: Andre Przywara <andre.przywara-5wv7dgnIgG8@public.gmane.org>
---
 drivers/mmc/host/sunxi-mmc.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/mmc/host/sunxi-mmc.c b/drivers/mmc/host/sunxi-mmc.c
index 8e7f3e35ee3d..c18cf035ac00 100644
--- a/drivers/mmc/host/sunxi-mmc.c
+++ b/drivers/mmc/host/sunxi-mmc.c
@@ -1407,7 +1407,10 @@ static int sunxi_mmc_probe(struct platform_device *pdev)
 	if (ret)
 		goto error_free_dma;
 
-	dev_info(&pdev->dev, "base:0x%p irq:%u\n", host->reg_base, host->irq);
+	dev_info(&pdev->dev, "initialized, max. request size: %u KB%s\n",
+		 mmc->max_req_size >> 10,
+		 host->use_new_timings ? ", uses new timings mode" : "");
+
 	return 0;
 
 error_free_dma:
-- 
2.14.4

Re: [PATCH v3] mmc: sunxi: remove output of virtual base address

[Maxime Ripard]

[-- Attachment #1: Type: text/plain, Size: 1520 bytes --]

On Mon, Jul 23, 2018 at 04:34:31PM +0100, Andre Przywara wrote:
> Recent Linux versions refuse to print actual virtual kernel addresses,
> to not give a hint about the location of the kernel in a randomized virtual
> address space. This affects the output of the sunxi MMC controller
> driver, which now produces the rather uninformative line:
> 
> [    1.482660] sunxi-mmc 1c0f000.mmc: base:0x(____ptrval____) irq:8
> 
> Since the virtual base address is not really interesting in the first
> place, let's just drop this value. The same applies to Linux' notion of
> the interrupt number, which is independent from the GIC SPI number.
> We have the physical address as part of the DT node name, which is way
> more useful for debugging purposes.
> To keep a success message in the driver, we make this purpose explicit
> with the word "initialized", plus print some information that is not too
> obvious and that we learned while probing the device:
> the maximum request size and whether it uses the new timing mode.
> So the output turns into:
> [    1.750626] sunxi-mmc 1c0f000.mmc: initialized, max. request size: 16384 KB, uses new timings mode
> [    1.786699] sunxi-mmc 1c11000.mmc: initialized, max. request size: 2048 KB
> 
> Signed-off-by: Andre Przywara <andre.przywara-5wv7dgnIgG8@public.gmane.org>

Acked-by: Maxime Ripard <maxime.ripard-LDxbnhwyfcJBDgjK7y7TUQ@public.gmane.org>

Thanks!
Maxime

-- 
Maxime Ripard, Bootlin (formerly Free Electrons)
Embedded Linux and Kernel engineering
https://bootlin.com

Re: [PATCH v3] mmc: sunxi: remove output of virtual base address

[Ulf Hansson]

On 23 July 2018 at 17:34, Andre Przywara <andre.przywara-5wv7dgnIgG8@public.gmane.org> wrote:
> Recent Linux versions refuse to print actual virtual kernel addresses,
> to not give a hint about the location of the kernel in a randomized virtual
> address space. This affects the output of the sunxi MMC controller
> driver, which now produces the rather uninformative line:
>
> [    1.482660] sunxi-mmc 1c0f000.mmc: base:0x(____ptrval____) irq:8
>
> Since the virtual base address is not really interesting in the first
> place, let's just drop this value. The same applies to Linux' notion of
> the interrupt number, which is independent from the GIC SPI number.
> We have the physical address as part of the DT node name, which is way
> more useful for debugging purposes.
> To keep a success message in the driver, we make this purpose explicit
> with the word "initialized", plus print some information that is not too
> obvious and that we learned while probing the device:
> the maximum request size and whether it uses the new timing mode.
> So the output turns into:
> [    1.750626] sunxi-mmc 1c0f000.mmc: initialized, max. request size: 16384 KB, uses new timings mode
> [    1.786699] sunxi-mmc 1c11000.mmc: initialized, max. request size: 2048 KB
>
> Signed-off-by: Andre Przywara <andre.przywara-5wv7dgnIgG8@public.gmane.org>

Thanks, applied for next!

Kind regards
Uffe

> ---
>  drivers/mmc/host/sunxi-mmc.c | 5 ++++-
>  1 file changed, 4 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/mmc/host/sunxi-mmc.c b/drivers/mmc/host/sunxi-mmc.c
> index 8e7f3e35ee3d..c18cf035ac00 100644
> --- a/drivers/mmc/host/sunxi-mmc.c
> +++ b/drivers/mmc/host/sunxi-mmc.c
> @@ -1407,7 +1407,10 @@ static int sunxi_mmc_probe(struct platform_device *pdev)
>         if (ret)
>                 goto error_free_dma;
>
> -       dev_info(&pdev->dev, "base:0x%p irq:%u\n", host->reg_base, host->irq);
> +       dev_info(&pdev->dev, "initialized, max. request size: %u KB%s\n",
> +                mmc->max_req_size >> 10,
> +                host->use_new_timings ? ", uses new timings mode" : "");
> +
>         return 0;
>
>  error_free_dma:
> --
> 2.14.4
>