Hi Chun-Kuang, On Tue, Sep 14, 2021 at 07:25:48AM +0800, Chun-Kuang Hu wrote: > Hi, Markus: > > Markus Schneider-Pargmann <msp@xxxxxxxxxxxx> 於 2021年9月10日 週五 下午1:36寫道: > > > > Hi Chun-Kuang, > > > > On Fri, Sep 10, 2021 at 07:37:50AM +0800, Chun-Kuang Hu wrote: > > > Hi, Markus: > > > > > > Markus Schneider-Pargmann <msp@xxxxxxxxxxxx> 於 2021年9月7日 週二 上午3:37寫道: > > > > > > > > This patch adds a DisplayPort driver for the Mediatek mt8195 SoC. > > > > > > > > It supports both functional units on the mt8195, the embedded > > > > DisplayPort as well as the external DisplayPort units. It offers > > > > hot-plug-detection, audio up to 8 channels, and DisplayPort 1.4 with up > > > > to 4 lanes. > > > > > > > > This driver is based on an initial version by > > > > Jason-JH.Lin <jason-jh.lin@xxxxxxxxxxxx>. > > > > > > > > Signed-off-by: Markus Schneider-Pargmann <msp@xxxxxxxxxxxx> > > > > --- > > > > > > > > Notes: > > > > Changes RFC -> v1: > > > > - Removed unused register definitions. > > > > - Replaced workqueue with threaded irq. > > > > - Removed connector code. > > > > - Move to atomic_* drm functions. > > > > - General cleanups of the code. > > > > - Remove unused select GENERIC_PHY. > > > > > > > > drivers/gpu/drm/mediatek/Kconfig | 6 + > > > > drivers/gpu/drm/mediatek/Makefile | 2 + > > > > drivers/gpu/drm/mediatek/mtk_dp.c | 2881 +++++++++++++++++++++++++ > > > > drivers/gpu/drm/mediatek/mtk_dp_reg.h | 580 +++++ > > > > 4 files changed, 3469 insertions(+) > > > > create mode 100644 drivers/gpu/drm/mediatek/mtk_dp.c > > > > create mode 100644 drivers/gpu/drm/mediatek/mtk_dp_reg.h > > > > > > > > ... > > > > > > +#define TOP_OFFSET 0x2000 > > > > +#define ENC0_OFFSET 0x3000 > > > > +#define ENC1_OFFSET 0x3200 > > > > +#define TRANS_OFFSET 0x3400 > > > > +#define AUX_OFFSET 0x3600 > > > > +#define SEC_OFFSET 0x4000 > > > > ... > > > > > > + > > > > +#define DP_PHY_DIG_PLL_CTL_1 0x1014 > > > > +# define TPLL_SSC_EN BIT(3) > > > > > > It seems that register 0x1000 ~ 0x1fff is to control phy and 0x2000 ~ > > > 0x4fff is to control non-phy part. For mipi and hdmi, the phy part is > > > an independent device [1] and the phy driver is independent [2] , so I > > > would like this phy to be an independent device. > > > > > > [1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/arch/arm64/boot/dts/mediatek/mt8173.dtsi?h=v5.14 > > > [2] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/phy/mediatek?h=v5.14 > > > > Thanks for your feedback. I looked into both mipi and hdmi phy drivers > > that you referenced. It looks like both are really separate units in > > their SoCs having their own registerspaces located at a completely > > different range than the units using the phy. > > > > For this displayport driver, the phy registers are listed as part of the > > (e)DP_TX unit in the datasheet. Next to the phy registers all the other > > parts are listed as well in the same overall register ranges (see > > above), e.g. TOP_OFFSET, ENC_OFFSET or SEC_OFFSET. Also I would like to > > avoid splitting it up into a separate unit in the devicetree as the > > datasheet handles it as a single unit (including the phy registers). > > OK, according to the datasheet, let it to be a single device. > > > > > From a practical perspective there is also not much to these PHY > > registers. The only things that would be done in the driver are: > > - initializing the lane driving parameters with static values > > - setup the bitrate > > - enable/disable SSC > > - do a reset > > Exporting these four used functions over a driver boundary wouldn't help > > clarity I think and the code probably can't be reused by any other > > component anyways. > > Use mmsys device [1] as an example. mmsys has both clock control > function and other function including routing function. The main > driver [2] is placed in soc folder, and the clock control part [3] is > separated to clk folder but the clock control part just simply control > clock gating. > > [1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/arch/arm64/boot/dts/mediatek/mt8173.dtsi?h=v5.15-rc1#n992 > [2] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/soc/mediatek/mtk-mmsys.c?h=v5.15-rc1 > [3] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/clk/mediatek/clk-mt8173-mm.c?h=v5.15-rc1 > > I think many phy driver could be used only by single device driver, so > we don't need to consider the reusability. Thank you, I have split of a display port phy similar to the patches you cited. I will send the next version soon. Another short question. This series has a functional dependency on the rest of the video pipeline, so mostly the patch series vdosys0 and vdosys1. So I suppose the theoretical order for merging (once this series is ready for merge) is first vdosys0/1 and dependencies and then this displayport series, is that correct? Thanks, Markus > > Regards, > Chun-Kuang. > > > > > So I personally would prefer keeping it as part of the whole driver > > because of the above mentioned reasons. What do you think? > > > > Thanks, > > Markus > > > > > > > > Regards, > > > Chun-Kuang. > > > > > > > + > > > > +#define DP_PHY_DIG_BIT_RATE 0x103C > > > > +# define BIT_RATE_RBR 0 > > > > +# define BIT_RATE_HBR 1 > > > > +# define BIT_RATE_HBR2 2 > > > > +# define BIT_RATE_HBR3 3 > > > > + > > > > +#define DP_PHY_DIG_SW_RST 0x1038 > > > > +# define DP_GLB_SW_RST_PHYD BIT(0) > > > > + > > > > +#define MTK_DP_LANE0_DRIVING_PARAM_3 0x1138 > > > > +#define MTK_DP_LANE1_DRIVING_PARAM_3 0x1238 > > > > +#define MTK_DP_LANE2_DRIVING_PARAM_3 0x1338 > > > > +#define MTK_DP_LANE3_DRIVING_PARAM_3 0x1438 > > > > +# define XTP_LN_TX_LCTXC0_SW0_PRE0_DEFAULT 0x10 > > > > +# define XTP_LN_TX_LCTXC0_SW0_PRE1_DEFAULT (0x14 << 8) > > > > +# define XTP_LN_TX_LCTXC0_SW0_PRE2_DEFAULT (0x18 << 16) > > > > +# define XTP_LN_TX_LCTXC0_SW0_PRE3_DEFAULT (0x20 << 24) > > > > +# define DRIVING_PARAM_3_DEFAULT (XTP_LN_TX_LCTXC0_SW0_PRE0_DEFAULT | \ > > > > + XTP_LN_TX_LCTXC0_SW0_PRE1_DEFAULT | \ > > > > + XTP_LN_TX_LCTXC0_SW0_PRE2_DEFAULT | \ > > > > + XTP_LN_TX_LCTXC0_SW0_PRE3_DEFAULT) > > > > + > > > > +#define MTK_DP_LANE0_DRIVING_PARAM_4 0x113C > > > > +#define MTK_DP_LANE1_DRIVING_PARAM_4 0x123C > > > > +#define MTK_DP_LANE2_DRIVING_PARAM_4 0x133C > > > > +#define MTK_DP_LANE3_DRIVING_PARAM_4 0x143C > > > > +# define XTP_LN_TX_LCTXC0_SW1_PRE0_DEFAULT 0x18 > > > > +# define XTP_LN_TX_LCTXC0_SW1_PRE1_DEFAULT (0x1e << 8) > > > > +# define XTP_LN_TX_LCTXC0_SW1_PRE2_DEFAULT (0x24 << 16) > > > > +# define XTP_LN_TX_LCTXC0_SW2_PRE0_DEFAULT (0x20 << 24) > > > > +# define DRIVING_PARAM_4_DEFAULT (XTP_LN_TX_LCTXC0_SW1_PRE0_DEFAULT | \ > > > > + XTP_LN_TX_LCTXC0_SW1_PRE1_DEFAULT | \ > > > > + XTP_LN_TX_LCTXC0_SW1_PRE2_DEFAULT | \ > > > > + XTP_LN_TX_LCTXC0_SW2_PRE0_DEFAULT) > > > > + > > > > +#define MTK_DP_LANE0_DRIVING_PARAM_5 0x1140 > > > > +#define MTK_DP_LANE1_DRIVING_PARAM_5 0x1240 > > > > +#define MTK_DP_LANE2_DRIVING_PARAM_5 0x1340 > > > > +#define MTK_DP_LANE3_DRIVING_PARAM_5 0x1440 > > > > +# define XTP_LN_TX_LCTXC0_SW2_PRE1_DEFAULT 0x28 > > > > +# define XTP_LN_TX_LCTXC0_SW3_PRE0_DEFAULT (0x30 << 8) > > > > +# define DRIVING_PARAM_5_DEFAULT (XTP_LN_TX_LCTXC0_SW2_PRE1_DEFAULT | \ > > > > + XTP_LN_TX_LCTXC0_SW3_PRE0_DEFAULT) > > > > + > > > > +#define MTK_DP_LANE0_DRIVING_PARAM_6 0x1144 > > > > +#define MTK_DP_LANE1_DRIVING_PARAM_6 0x1244 > > > > +#define MTK_DP_LANE2_DRIVING_PARAM_6 0x1344 > > > > +#define MTK_DP_LANE3_DRIVING_PARAM_6 0x1444 > > > > +# define XTP_LN_TX_LCTXCP1_SW0_PRE0_DEFAULT 0x00 > > > > +# define XTP_LN_TX_LCTXCP1_SW0_PRE1_DEFAULT (0x04 << 8) > > > > +# define XTP_LN_TX_LCTXCP1_SW0_PRE2_DEFAULT (0x08 << 16) > > > > +# define XTP_LN_TX_LCTXCP1_SW0_PRE3_DEFAULT (0x10 << 24) > > > > +# define DRIVING_PARAM_6_DEFAULT (XTP_LN_TX_LCTXCP1_SW0_PRE0_DEFAULT | \ > > > > + XTP_LN_TX_LCTXCP1_SW0_PRE1_DEFAULT | \ > > > > + XTP_LN_TX_LCTXCP1_SW0_PRE2_DEFAULT | \ > > > > + XTP_LN_TX_LCTXCP1_SW0_PRE3_DEFAULT) > > > > + > > > > +#define MTK_DP_LANE0_DRIVING_PARAM_7 0x1148 > > > > +#define MTK_DP_LANE1_DRIVING_PARAM_7 0x1248 > > > > +#define MTK_DP_LANE2_DRIVING_PARAM_7 0x1348 > > > > +#define MTK_DP_LANE3_DRIVING_PARAM_7 0x1448 > > > > +# define XTP_LN_TX_LCTXCP1_SW1_PRE0_DEFAULT 0x00 > > > > +# define XTP_LN_TX_LCTXCP1_SW1_PRE1_DEFAULT (0x06 << 8) > > > > +# define XTP_LN_TX_LCTXCP1_SW1_PRE2_DEFAULT (0x0c << 16) > > > > +# define XTP_LN_TX_LCTXCP1_SW2_PRE0_DEFAULT (0x00 << 24) > > > > +# define DRIVING_PARAM_7_DEFAULT (XTP_LN_TX_LCTXCP1_SW1_PRE0_DEFAULT | \ > > > > + XTP_LN_TX_LCTXCP1_SW1_PRE1_DEFAULT | \ > > > > + XTP_LN_TX_LCTXCP1_SW1_PRE2_DEFAULT | \ > > > > + XTP_LN_TX_LCTXCP1_SW2_PRE0_DEFAULT) > > > > + > > > > +#define MTK_DP_LANE0_DRIVING_PARAM_8 0x114C > > > > +#define MTK_DP_LANE1_DRIVING_PARAM_8 0x124C > > > > +#define MTK_DP_LANE2_DRIVING_PARAM_8 0x134C > > > > +#define MTK_DP_LANE3_DRIVING_PARAM_8 0x144C > > > > +# define XTP_LN_TX_LCTXCP1_SW2_PRE1_DEFAULT 0x08 > > > > +# define XTP_LN_TX_LCTXCP1_SW3_PRE0_DEFAULT (0x00 << 8) > > > > +# define DRIVING_PARAM_8_DEFAULT (XTP_LN_TX_LCTXCP1_SW2_PRE1_DEFAULT | \ > > > > + XTP_LN_TX_LCTXCP1_SW3_PRE0_DEFAULT) > > > > + > > > > +#endif /*_MTK_DP_REG_H_*/ > > > > -- > > > > 2.33.0 > > > >