[PATCH v1 06/15] drm/mediatek: add memory mode for RDMA

Stu Hsieh
2018-08-02T11:36:26Z

Hi, CK:

On Wed, 2018-07-25 at 10:40 +0800, CK Hu wrote:
> Hi, Stu:
>
> On Tue, 2018-07-24 at 16:17 +0800, Stu Hsieh wrote:
> > This patch add memory mode for RDMA
> >
> > If use RDMA to read data from memory, it should set memory mode to RDMA
> >
> > Signed-off-by: Stu Hsieh <stu.hsieh@mediatek.com>
> > ---
> > drivers/gpu/drm/mediatek/mtk_disp_rdma.c | 16 +++++++++++++++-
> > 1 file changed, 15 insertions(+), 1 deletion(-)
> >
>
> [...]
>
> > static inline struct mtk_disp_rdma *comp_to_rdma(struct mtk_ddp_comp *comp)
> > @@ -111,7 +116,8 @@ static void mtk_rdma_start(struct mtk_ddp_comp *comp)
> >
> > static void mtk_rdma_stop(struct mtk_ddp_comp *comp)
> > {
> > - rdma_update_bits(comp, DISP_REG_RDMA_GLOBAL_CON, RDMA_ENGINE_EN, 0);
> > + writel(RDMA_SOFT_RESET, comp->regs + DISP_REG_RDMA_GLOBAL_CON);
> > + writel(0, comp->regs + DISP_REG_RDMA_GLOBAL_CON);
>
> Without reset, what happen to dram mode? Why direct link mode need not
> this reset?
>

There is nothing to happen, I would remove it.

> > }
> >
> > static void mtk_rdma_config(struct mtk_ddp_comp *comp, unsigned int width,
> > @@ -121,10 +127,18 @@ static void mtk_rdma_config(struct mtk_ddp_comp *comp, unsigned int width,
> > unsigned int threshold;
> > unsigned int reg;
> > struct mtk_disp_rdma *rdma = comp_to_rdma(comp);
> > + bool *rdma_memory_mode = comp->comp_mode;
> >
> > rdma_update_bits(comp, DISP_REG_RDMA_SIZE_CON_0, 0xfff, width);
> > rdma_update_bits(comp, DISP_REG_RDMA_SIZE_CON_1, 0xfffff, height);
> >
> > + if (*rdma_memory_mode == true) {
> > + rdma_update_bits(comp, DISP_REG_RDMA_SIZE_CON_0, 0xff0000,
> > + MATRIX_INT_MTX_SEL_DEFAULT);
> > + rdma_update_bits(comp, DISP_REG_RDMA_GLOBAL_CON,
> > + RDMA_MODE_MEMORY, RDMA_MODE_MEMORY);
> > + }
> > +
>
> I would like this to be a kind of 'layer' config. In some SoC, one layer
> of OVL could switch to direct link input or dram input. So I think it's
> better to move this setting into some layer interface.
>
> Regards,
> CK
>

If move it to layer_config, RDMA would not trigger interrupt.
In the future, when cmdq patch upstream and accepted, this part can move
to layer_config.

Regard,
Stu

> > /*
> > * Enable FIFO underflow since DSI and DPI can't be blocked.
> > * Keep the FIFO pseudo size reset default of 8 KiB. Set the
>
>