From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 34BADC433F5 for ; Mon, 8 Nov 2021 16:31:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0FB7261378 for ; Mon, 8 Nov 2021 16:31:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239999AbhKHQdt convert rfc822-to-8bit (ORCPT ); Mon, 8 Nov 2021 11:33:49 -0500 Received: from aposti.net ([89.234.176.197]:57300 "EHLO aposti.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232506AbhKHQds (ORCPT ); Mon, 8 Nov 2021 11:33:48 -0500 Date: Mon, 08 Nov 2021 16:30:47 +0000 From: Paul Cercueil Subject: Re: [PATCH v5 2/7] drm/ingenic: Add support for JZ4780 and HDMI output To: "H. Nikolaus Schaller" Cc: Rob Herring , Mark Rutland , Thomas Bogendoerfer , Geert Uytterhoeven , Kees Cook , "Eric W. Biederman" , Miquel Raynal , David Airlie , Daniel Vetter , Neil Armstrong , Robert Foss , Laurent Pinchart , Jernej Skrabec , Harry Wentland , Sam Ravnborg , Maxime Ripard , Hans Verkuil , Liam Girdwood , Mark Brown , Paul Boddie , OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS , linux-mips , linux-kernel , Discussions about the Letux Kernel , Jonas Karlman , dri-devel Message-Id: In-Reply-To: References: <2c7d0aa7d3ef480ebb996d37c27cbaa6f722728b.1633436959.git.hns@goldelico.com> <7CEBB741-2218-40A7-9800-B3A154895274@goldelico.com> <229EBE4C-6555-41DE-962F-D82798AEC650@goldelico.com> <2E32F572-72D0-44E7-A700-AF8A2D37BFDA@goldelico.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1; format=flowed Content-Transfer-Encoding: 8BIT Precedence: bulk List-ID: X-Mailing-List: linux-mips@vger.kernel.org Hi, Le lun., nov. 8 2021 at 16:29:11 +0100, H. Nikolaus Schaller a écrit : > Bnjour Paul, > > >> Am 08.11.2021 um 13:20 schrieb Paul Cercueil : >> >> Hi, >> >> Le lun., nov. 8 2021 at 11:52:20 +0100, H. Nikolaus Schaller >> a écrit : >>> Hi Paul, >>>>> Am 08.11.2021 um 10:37 schrieb Paul Cercueil >>>>> : >>>>> Well, it was atomic: "add jz4780+hdmi functionality" or not. Now >>>>> we separate into "preparation for adding jz4780" and "really >>>>> adding". Yes, you can split atoms into quarks... >>>> And that's how it should be done. Lots of small atomic patches >>>> are much easier to review than a few big patches. >>> I doubt that in this case especially as it has nothing to do with >>> jz4780... >> >> It has nothing to do with JZ4780 and that's exactly why it should >> be a separate patch. > > Question is why *I* should then make this patch and not someone > else... > > I am not necessarily a volunteer to contribute to non-jz4780 code > just because I want to upstream jz4780 code. The JZ4780 patch lies on top of the other one, so they are still related. They just shouldn't be the same patch. >> >>> But I have a proposal for a better solution at the end of this >>> mail. >>>>>> Note that you can do even better, set the .max_register field >>>>>> according to the memory resource you get from DTS. Have a look >>>>>> at the pinctrl driver which does exactly this. >>>>> That is an interesting idea. Although I don't see where >>>>> >>>>> https://elixir.bootlin.com/linux/latest/source/drivers/pinctrl/pinctrl-ingenic.c#L4171 >>>>> does make use of the memory resource from DTS. It just reads two >>>>> values from the ingenic_chip_info instead of one I do read from >>>>> soc_info. >>>> It overrides the .max_register from a static regmap_config >>>> instance. >>> To be precise: it overrides .max_register of a copy of a static >>> regmap_config instance (which has .max_register = 0). >>>> You can do the same, >>> We already do the same... >>>> calculating the .max_register from the memory resource you get >>>> from DT. >>> I can't see any code in pinctrl-ingenic.c getting the memory >>> resource that from DT. It calculates it from the ingenic_chip_info >>> tables inside the driver code but not DT. >>>> I'm sure you guys can figure it out. >>> Ah, we have to figure out. You are not sure yourself how to do it? >>> And it is *not* exactly like the pinctrl driver (already) does? >>> Please give precise directions in reviews and not vague research >>> homework. Our time is also valuable. Sorry if I review your >>> reviews... >>> Anyways I think you roughly intend (untested): >>> struct resource *r; >>> r = platform_get_resource(pdev, IORESOURCE_MEM, 0); >>> regmap_config.max_register = r.end - r.start; >> >> Replace the "devm_platform_ioremap_resource" with >> "devm_platform_get_and_ioremap_resource" to get a pointer to the >> resource. >> >> Then the .max_register should be (r.end - r.start - 4) I think. >> >> And lose the aggressivity. It's not going to get you anywhere, >> especially since I'm the one who decides whether or not I should >> merge your patches. You want your code upstream, that's great, but >> it's your responsability to get it to shape so that it's eventually >> accepted. > > Well on the other side of the fence it is maintainers responsibility > to give clear and understandable rules and guidance about what will > be accepted and to enable us to bring it into the shape he/she has in > mind. > > But a fundamental problem is: "good shape" is very subjective. What > would you recommend me to do, if I feel that my proposed code is in > better shape than what the maintainer thinks or recommends? > >> >>> But I wonder how that could work at all (despite adding code >>> execution time) with: >> >> Code execution time? ... > > I reasoned about doing an additional platform_get_resource() call and > doing a subtraction. This is additional execution time. Maybe not > worth thinking about because it is in the probe function. And using > devm_platform_get_and_ioremap_resource() is of course potentially > better. > >> >>> e.g. jz4770.dtsi: >>> lcd: lcd-controller@13050000 { >>> compatible = "ingenic,jz4770-lcd"; >>> reg = <0x13050000 0x300>; >>> or jz4725b.dtsi: >>> lcd: lcd-controller@13050000 { >>> compatible = "ingenic,jz4725b-lcd"; >>> reg = <0x13050000 0x1000>; >>> So max_register becomes 0x300 or 0x1000 but not >>> #define JZ_REG_LCD_SIZE1 0x12c >>> .max_reg = JZ_REG_LCD_SIZE1, >>> And therefore wastes a lot of regmap memory. >> >> "regmap memory"? ... > > regmap allocates memory for its cache. Usually the total amount > specified in the reg property. We are not using any register cache here. >> >>> Do you want this? DTS should not be reduced (DTS should be kept as >>> stable as possible), since the reg property describes address >>> mapping - not how many bytes are really used by registers or how >>> big a cache should be allocated (cache allocation size requirements >>> are not hardware description). >> >> The DTS should list the address and size of the register area. If >> your last register is at address 0x12c and there's nothing above, >> then the size in DTS should be 0x130. > > If I look into some .dtsi it is sometimes that way but sometimes not. > There seems to be no consistent rule. > > So does this mean you allow me to modify jz4740.dtsi, jz4770.dtsi and > jz4725b.dtsi as well (as mentioned above: this is beyond the scope of > my project)? You could update them if you wanted to, but there is no need to do it here. >> >>> But here are good news: >>> I have a simpler and less invasive proposal. We keep the >>> devm_regmap_init_mmio code as is and just increase its >>> .max_register from JZ_REG_LCD_SIZE1 to JZ_REG_LCD_PCFG when >>> introducing the jz4780. This wastes a handful bytes for all >>> non-jz4780 chips but less than using the DTS memory region size. >>> And is less code (no entry in soc_info tables, no modifyable copy) >>> and faster code execution than all other proposals. >>> This is then just a single-line change when introducing the >>> jz4780. And no "preparation for adding jz4780" patch is needed at >>> all. No patch to split out for separate review. >>> Let's go this way to get it eventually finalized. Ok? >> >> No. > > Look friend, if you explain your "no" and what is wrong with my > arguments, it helps to understand your decisions and learn something > from them. A plain "no" does not help anyone. I answered just "no" because I felt like I explained already what I wanted to see in the previous email. By using a huge number as the .max_register, we do *not* waste additional memory. Computing the value of the .max_register field does not add any overhead, either. The .max_register is only used for boundary checking. To make sure that you're not calling regmap_write() with an invalid register. That's all there is to it. > So to summarize: if you prefer something which I consider worse, it > is ok for me... In the end you are right - you are the maintainer, > not me. So you have to live with your proposals. > > Therefore, I have prepared new variants so you can choose which one > is easier to maintain for you. > > Note that they are both preparing for full jz4780-lcdc/hdmi support > but in very different ways: > > Variant 1 already adds some jz4780 stuff while Variant 2 just > prepares for it. > > Variant 2 is not tested (except to compile). So it needs some > Tested-by: from someone with access to hardware. IMHO it is more > invasive. > > And don't forget: DTB could be in ROM or be provided by a separate > bootloader... So we should not change it too often (I had such > discussions some years ago with maintainers when I thought it is > easier to change DTS instead of code). > > Variant 3 would be to not separate this. As proposed in [PATCH v5 > 2/7]. > (Finally, a Variant 3b would be to combine the simple change from > Variant 1 with Variant 3). > > So what is your choice? Variant 4: the variant #2 without the changes to the DTSI files. Cheers, -Paul > BR and thanks, > Nikolaus > > > #### VARIANT 0001 #### > > From c7afa925f6b53bb6cafa080b7dd582788c8eb2eb Mon Sep 17 00:00:00 2001 > From: "H. Nikolaus Schaller" > Date: Mon, 8 Nov 2021 15:38:21 +0100 > Subject: [PATCH] RFC: drm/ingenic: Add register definitions for > JZ4780 lcdc > > JZ4780 has additional registers compared to the other > SoC of the JZ47xx series. So we add the constants for > registers and bits we make use of (there are even more > which can be added later). > > And we increase the regmap max_register accordingly. > > Signed-off-by: H. Nikolaus Schaller > --- > drivers/gpu/drm/ingenic/ingenic-drm-drv.c | 2 +- > drivers/gpu/drm/ingenic/ingenic-drm.h | 39 > +++++++++++++++++++++++ > 2 files changed, 40 insertions(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/ingenic/ingenic-drm-drv.c > b/drivers/gpu/drm/ingenic/ingenic-drm-drv.c > index a5df1c8d34cde..1903e897d2299 100644 > --- a/drivers/gpu/drm/ingenic/ingenic-drm-drv.c > +++ b/drivers/gpu/drm/ingenic/ingenic-drm-drv.c > @@ -122,7 +122,7 @@ static const struct regmap_config > ingenic_drm_regmap_config = { > .val_bits = 32, > .reg_stride = 4, > > - .max_register = JZ_REG_LCD_SIZE1, > + .max_register = JZ_REG_LCD_PCFG, > .writeable_reg = ingenic_drm_writeable_reg, > }; > > diff --git a/drivers/gpu/drm/ingenic/ingenic-drm.h > b/drivers/gpu/drm/ingenic/ingenic-drm.h > index 22654ac1dde1c..e7430c4af41f6 100644 > --- a/drivers/gpu/drm/ingenic/ingenic-drm.h > +++ b/drivers/gpu/drm/ingenic/ingenic-drm.h > @@ -44,8 +44,11 @@ > #define JZ_REG_LCD_XYP1 0x124 > #define JZ_REG_LCD_SIZE0 0x128 > #define JZ_REG_LCD_SIZE1 0x12c > +#define JZ_REG_LCD_PCFG 0x2c0 > > #define JZ_LCD_CFG_SLCD BIT(31) > +#define JZ_LCD_CFG_DESCRIPTOR_8 BIT(28) > +#define JZ_LCD_CFG_RECOVER_FIFO_UNDERRUN BIT(25) > #define JZ_LCD_CFG_PS_DISABLE BIT(23) > #define JZ_LCD_CFG_CLS_DISABLE BIT(22) > #define JZ_LCD_CFG_SPL_DISABLE BIT(21) > @@ -63,6 +66,7 @@ > #define JZ_LCD_CFG_DE_ACTIVE_LOW BIT(9) > #define JZ_LCD_CFG_VSYNC_ACTIVE_LOW BIT(8) > #define JZ_LCD_CFG_18_BIT BIT(7) > +#define JZ_LCD_CFG_24_BIT BIT(6) > #define JZ_LCD_CFG_PDW (BIT(5) | BIT(4)) > > #define JZ_LCD_CFG_MODE_GENERIC_16BIT 0 > @@ -132,6 +136,7 @@ > #define JZ_LCD_CMD_SOF_IRQ BIT(31) > #define JZ_LCD_CMD_EOF_IRQ BIT(30) > #define JZ_LCD_CMD_ENABLE_PAL BIT(28) > +#define JZ_LCD_CMD_FRM_ENABLE BIT(26) > > #define JZ_LCD_SYNC_MASK 0x3ff > > @@ -153,6 +158,7 @@ > #define JZ_LCD_RGBC_EVEN_BGR (0x5 << 0) > > #define JZ_LCD_OSDC_OSDEN BIT(0) > +#define JZ_LCD_OSDC_ALPHAEN BIT(2) > #define JZ_LCD_OSDC_F0EN BIT(3) > #define JZ_LCD_OSDC_F1EN BIT(4) > > @@ -176,6 +182,39 @@ > #define JZ_LCD_SIZE01_WIDTH_LSB 0 > #define JZ_LCD_SIZE01_HEIGHT_LSB 16 > > +#define JZ_LCD_DESSIZE_ALPHA_OFFSET 24 > +#define JZ_LCD_DESSIZE_HEIGHT_MASK GENMASK(23, 12) > +#define JZ_LCD_DESSIZE_WIDTH_MASK GENMASK(11, 0) > + > +/* TODO: 4,5 and 7 match the above BPP */ > +#define JZ_LCD_CPOS_BPP_15_16 (4 << 27) > +#define JZ_LCD_CPOS_BPP_18_24 (5 << 27) > +#define JZ_LCD_CPOS_BPP_30 (7 << 27) > +#define JZ_LCD_CPOS_RGB555 BIT(30) > +#define JZ_LCD_CPOS_PREMULTIPLY_LCD BIT(26) > +#define JZ_LCD_CPOS_COEFFICIENT_OFFSET 24 > +#define JZ_LCD_CPOS_COEFFICIENT_0 0 > +#define JZ_LCD_CPOS_COEFFICIENT_1 1 > +#define JZ_LCD_CPOS_COEFFICIENT_ALPHA1 2 > +#define JZ_LCD_CPOS_COEFFICIENT_1_ALPHA1 3 > + > +#define JZ_LCD_RGBC_RGB_PADDING BIT(15) > +#define JZ_LCD_RGBC_RGB_PADDING_FIRST BIT(14) > +#define JZ_LCD_RGBC_422 BIT(8) > +#define JZ_LCD_RGBC_RGB_FORMAT_ENABLE BIT(7) > + > +#define JZ_LCD_PCFG_PRI_MODE BIT(31) > +#define JZ_LCD_PCFG_HP_BST_4 (0 << 28) > +#define JZ_LCD_PCFG_HP_BST_8 (1 << 28) > +#define JZ_LCD_PCFG_HP_BST_16 (2 << 28) > +#define JZ_LCD_PCFG_HP_BST_32 (3 << 28) > +#define JZ_LCD_PCFG_HP_BST_64 (4 << 28) > +#define JZ_LCD_PCFG_HP_BST_16_CONT (5 << 28) > +#define JZ_LCD_PCFG_HP_BST_DISABLE (7 << 28) > +#define JZ_LCD_PCFG_THRESHOLD2_OFFSET 18 > +#define JZ_LCD_PCFG_THRESHOLD1_OFFSET 9 > +#define JZ_LCD_PCFG_THRESHOLD0_OFFSET 0 > + > struct device; > struct drm_plane; > struct drm_plane_state; > -- > 2.33.0 > > > #### VARIANT 0002 #### > > From c4b5cfa2789493f02da91e385719bc97aefb6c6c Mon Sep 17 00:00:00 2001 > From: "H. Nikolaus Schaller" > Date: Mon, 8 Nov 2021 14:40:58 +0100 > Subject: [PATCH] RFC: drm/ingenic: prepare ingenic drm for later > addition of > JZ4780 > > This changes the way the regmap is allocated to prepare for the > later addition of the JZ4780 which has more registers and bits > than the others. > > To make this work we have to change the device tree records of > all devices so that the reg property is limited to the physically > available registers. > > The magic value 0x130 in the device tree is JZ_REG_LCD_SIZE1 + 4. > > Note that it is not tested since I have no access to the hardware. > > Suggested-by: Paul Cercueil > Signed-off-by: H. Nikolaus Schaller > --- > arch/mips/boot/dts/ingenic/jz4725b.dtsi | 2 +- > arch/mips/boot/dts/ingenic/jz4740.dtsi | 2 +- > arch/mips/boot/dts/ingenic/jz4770.dtsi | 2 +- > drivers/gpu/drm/ingenic/ingenic-drm-drv.c | 9 ++++++--- > 4 files changed, 9 insertions(+), 6 deletions(-) > > diff --git a/arch/mips/boot/dts/ingenic/jz4725b.dtsi > b/arch/mips/boot/dts/ingenic/jz4725b.dtsi > index a1f0b71c92237..c017b087c0e52 100644 > --- a/arch/mips/boot/dts/ingenic/jz4725b.dtsi > +++ b/arch/mips/boot/dts/ingenic/jz4725b.dtsi > @@ -321,7 +321,7 @@ udc: usb@13040000 { > > lcd: lcd-controller@13050000 { > compatible = "ingenic,jz4725b-lcd"; > - reg = <0x13050000 0x1000>; > + reg = <0x13050000 0x130>; > > interrupt-parent = <&intc>; > interrupts = <31>; > diff --git a/arch/mips/boot/dts/ingenic/jz4740.dtsi > b/arch/mips/boot/dts/ingenic/jz4740.dtsi > index c1afdfdaa8a38..ce3689e5015b5 100644 > --- a/arch/mips/boot/dts/ingenic/jz4740.dtsi > +++ b/arch/mips/boot/dts/ingenic/jz4740.dtsi > @@ -323,7 +323,7 @@ udc: usb@13040000 { > > lcd: lcd-controller@13050000 { > compatible = "ingenic,jz4740-lcd"; > - reg = <0x13050000 0x1000>; > + reg = <0x13050000 0x130>; > > interrupt-parent = <&intc>; > interrupts = <30>; > diff --git a/arch/mips/boot/dts/ingenic/jz4770.dtsi > b/arch/mips/boot/dts/ingenic/jz4770.dtsi > index 05c00b93088e9..0d1ee58d6c40b 100644 > --- a/arch/mips/boot/dts/ingenic/jz4770.dtsi > +++ b/arch/mips/boot/dts/ingenic/jz4770.dtsi > @@ -399,7 +399,7 @@ gpu: gpu@13040000 { > > lcd: lcd-controller@13050000 { > compatible = "ingenic,jz4770-lcd"; > - reg = <0x13050000 0x300>; > + reg = <0x13050000 0x130>; > > interrupt-parent = <&intc>; > interrupts = <31>; > diff --git a/drivers/gpu/drm/ingenic/ingenic-drm-drv.c > b/drivers/gpu/drm/ingenic/ingenic-drm-drv.c > index a5df1c8d34cde..3c8e3c5a447bb 100644 > --- a/drivers/gpu/drm/ingenic/ingenic-drm-drv.c > +++ b/drivers/gpu/drm/ingenic/ingenic-drm-drv.c > @@ -122,7 +122,6 @@ static const struct regmap_config > ingenic_drm_regmap_config = { > .val_bits = 32, > .reg_stride = 4, > > - .max_register = JZ_REG_LCD_SIZE1, > .writeable_reg = ingenic_drm_writeable_reg, > }; > > @@ -858,6 +857,8 @@ static int ingenic_drm_bind(struct device *dev, > bool has_components) > struct drm_encoder *encoder; > struct drm_device *drm; > void __iomem *base; > + struct resource *res; > + struct regmap_config regmap_config; > long parent_rate; > unsigned int i, clone_mask = 0; > dma_addr_t dma_hwdesc_phys_f0, dma_hwdesc_phys_f1; > @@ -904,14 +905,16 @@ static int ingenic_drm_bind(struct device *dev, > bool has_components) > drm->mode_config.funcs = &ingenic_drm_mode_config_funcs; > drm->mode_config.helper_private = &ingenic_drm_mode_config_helpers; > > - base = devm_platform_ioremap_resource(pdev, 0); > + base = devm_platform_get_and_ioremap_resource(pdev, 0, &res); > if (IS_ERR(base)) { > dev_err(dev, "Failed to get memory resource\n"); > return PTR_ERR(base); > } > > + regmap_config = ingenic_drm_regmap_config; > + regmap_config.max_register = res->end - res->start - 4; > priv->map = devm_regmap_init_mmio(dev, base, > - &ingenic_drm_regmap_config); > + ®map_config); > if (IS_ERR(priv->map)) { > dev_err(dev, "Failed to create regmap\n"); > return PTR_ERR(priv->map); > -- > 2.33.0 > >