[PATCH 2/2] ARM: imx51: Configure M4IF to avoid visual artifacts

[l.stach@pengutronix.de (Lucas Stach)]

Am Mittwoch, den 04.07.2018, 13:14 -0300 schrieb Fabio Estevam:
> From: Fabio Estevam <fabio.estevam@nxp.com>
> 
> Configure the M4IF registers as per the vendor bootloader
> to avoid visual artifacts during video playback.
> 
> This way we don't need to rely on the bootloader configuration for
> optimal IPU/VPU bus priorities.
> 
> Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com>

Reviewed-by: Lucas Stach <l.stach@pengutronix.de>

> ---
> ?arch/arm/mach-imx/mach-imx51.c | 29 ++++++++++++++++++++++++++++-
> ?1 file changed, 28 insertions(+), 1 deletion(-)
> 
> diff --git a/arch/arm/mach-imx/mach-imx51.c b/arch/arm/mach-imx/mach-
> imx51.c
> index 3835b6a..37ffdfa 100644
> --- a/arch/arm/mach-imx/mach-imx51.c
> +++ b/arch/arm/mach-imx/mach-imx51.c
> @@ -12,6 +12,7 @@
> ?
> ?#include <linux/io.h>
> ?#include <linux/irq.h>
> +#include <linux/of_address.h>
> ?#include <linux/of_irq.h>
> ?#include <linux/of_platform.h>
> ?#include <asm/mach/arch.h>
> @@ -48,11 +49,37 @@ static void __init imx51_ipu_mipi_setup(void)
> ?	iounmap(hsc_addr);
> ?}
> ?
> +static void __init imx51_m4if_setup(void)
> +{
> +	void __iomem *m4if_base;
> +	struct device_node *np;
> +
> +	np = of_find_compatible_node(NULL, NULL, "fsl,imx51-m4if");
> +	if (!np)
> +		return;
> +
> +	m4if_base = of_iomap(np, 0);
> +	if (!m4if_base) {
> +		pr_err("Unable to map M4IF registers\n");
> +		return;
> +	}
> +
> +	/*
> +	?* Configure VPU and IPU with higher priorities
> +	?* in order to avoid artifacts during video playback
> +	?*/
> +	writel_relaxed(0x00000203, m4if_base + 0x40);
> +	writel_relaxed(0x00000000, m4if_base + 0x44);
> +	writel_relaxed(0x00120125, m4if_base + 0x9c);
> +	writel_relaxed(0x001901A3, m4if_base + 0x48);
> +	iounmap(m4if_base);
> +}
> +
> ?static void __init imx51_dt_init(void)
> ?{
> ?	imx51_ipu_mipi_setup();
> ?	imx_src_init();
> -
> +	imx51_m4if_setup();
> ?	imx_aips_allow_unprivileged_access("fsl,imx51-aipstz");
> ?}
> ?