[PATCH 3/3] phy: rockchip: Add Samsung HDMI/DP Combo PHY driver
Jonas Karlman
jonas at kwiboo.se
Wed Jan 24 01:16:29 PST 2024
On 2024-01-24 08:30, Andy Yan wrote:
> Hi Cristian:
>
> On 1/24/24 10:42, Andy Yan wrote:
>> Hi Cristian:
>>
>> On 1/24/24 08:58, Cristian Ciocaltea wrote:
>>> On 1/22/24 14:14, Sascha Hauer wrote:
>>>> On Fri, Jan 19, 2024 at 09:38:03PM +0200, Cristian Ciocaltea wrote:
>>>>> Add driver for the Rockchip HDMI/eDP TX Combo PHY found on RK3588 SoC.
>>>>>
>>>>> The PHY is based on a Samsung IP block and supports HDMI 2.1 TMDS, FRL
>>>>> and eDP links. The maximum data rate is 12Gbps (HDMI 2.1 FRL), while
>>>>> the minimum is 250Mbps (HDMI 2.1 TMDS).
>>>>>
>>>>> Co-developed-by: Algea Cao <algea.cao at rock-chips.com>
>>>>> Signed-off-by: Algea Cao <algea.cao at rock-chips.com>
>>>>> Signed-off-by: Cristian Ciocaltea <cristian.ciocaltea at collabora.com>
>>>>> ---
>>>>> drivers/phy/rockchip/Kconfig | 8 +
>>>>> drivers/phy/rockchip/Makefile | 1 +
>>>>> .../phy/rockchip/phy-rockchip-samsung-hdptx.c | 2045 +++++++++++++++++
>>>>> 3 files changed, 2054 insertions(+)
>>>>> create mode 100644 drivers/phy/rockchip/phy-rockchip-samsung-hdptx.c
>>>>>
>>>>> diff --git a/drivers/phy/rockchip/Kconfig b/drivers/phy/rockchip/Kconfig
>>>>> index 94360fc96a6f..95666ac6aa3b 100644
>>>>> --- a/drivers/phy/rockchip/Kconfig
>>>>> +++ b/drivers/phy/rockchip/Kconfig
>>>>> @@ -83,6 +83,14 @@ config PHY_ROCKCHIP_PCIE
>>>>> help
>>>>> Enable this to support the Rockchip PCIe PHY.
>>>>> +config PHY_ROCKCHIP_SAMSUNG_HDPTX
>>>>> + tristate "Rockchip Samsung HDMI/DP Combo PHY driver"
>>>>> + depends on (ARCH_ROCKCHIP || COMPILE_TEST) && OF
>>>>> + select GENERIC_PHY
>>>>> + help
>>>>> + Enable this to support the Rockchip HDMI/DP Combo PHY
>>>>> + with Samsung IP block.
>>>>> +
>>>>> config PHY_ROCKCHIP_SNPS_PCIE3
>>>>> tristate "Rockchip Snps PCIe3 PHY Driver"
>>>>> depends on (ARCH_ROCKCHIP && OF) || COMPILE_TEST
>>>>> diff --git a/drivers/phy/rockchip/Makefile b/drivers/phy/rockchip/Makefile
>>>>> index 7eab129230d1..3d911304e654 100644
>>>>> --- a/drivers/phy/rockchip/Makefile
>>>>> +++ b/drivers/phy/rockchip/Makefile
>>>>> @@ -8,6 +8,7 @@ obj-$(CONFIG_PHY_ROCKCHIP_INNO_HDMI) += phy-rockchip-inno-hdmi.o
>>>>> obj-$(CONFIG_PHY_ROCKCHIP_INNO_USB2) += phy-rockchip-inno-usb2.o
>>>>> obj-$(CONFIG_PHY_ROCKCHIP_NANENG_COMBO_PHY) += phy-rockchip-naneng-combphy.o
>>>>> obj-$(CONFIG_PHY_ROCKCHIP_PCIE) += phy-rockchip-pcie.o
>>>>> +obj-$(CONFIG_PHY_ROCKCHIP_SAMSUNG_HDPTX) += phy-rockchip-samsung-hdptx.o
>>>>> obj-$(CONFIG_PHY_ROCKCHIP_SNPS_PCIE3) += phy-rockchip-snps-pcie3.o
>>>>> obj-$(CONFIG_PHY_ROCKCHIP_TYPEC) += phy-rockchip-typec.o
>>>>> obj-$(CONFIG_PHY_ROCKCHIP_USB) += phy-rockchip-usb.o
>>>>> diff --git a/drivers/phy/rockchip/phy-rockchip-samsung-hdptx.c b/drivers/phy/rockchip/phy-rockchip-samsung-hdptx.c
>>>>> new file mode 100644
>>>>> index 000000000000..d8171ea5ce2b
>>>>> --- /dev/null
>>>>> +++ b/drivers/phy/rockchip/phy-rockchip-samsung-hdptx.c
>>>>> @@ -0,0 +1,2045 @@
>>>>> +// SPDX-License-Identifier: GPL-2.0+
>>>>> +/*
>>>>> + * Copyright (c) 2021-2022 Rockchip Electronics Co., Ltd.
>>>>> + * Copyright (c) 2024 Collabora Ltd.
>>>>> + *
>>>>> + * Author: Algea Cao <algea.cao at rock-chips.com>
>>>>> + * Author: Cristian Ciocaltea <cristian.ciocaltea at collabora.com>
>>>>> + */
>>>>> +#include <linux/bitfield.h>
>>>>> +#include <linux/clk.h>
>>>>> +#include <linux/delay.h>
>>>>> +#include <linux/mfd/syscon.h>
>>>>> +#include <linux/module.h>
>>>>> +#include <linux/of.h>
>>>>> +#include <linux/of_platform.h>
>>>>> +#include <linux/phy/phy.h>
>>>>> +#include <linux/platform_device.h>
>>>>> +#include <linux/rational.h>
>>>>> +#include <linux/regmap.h>
>>>>> +#include <linux/reset.h>
>>>>> +
>>>>> +#define GRF_HDPTX_CON0 0x00
>>>>> +#define HDPTX_I_PLL_EN BIT(7)
>>>>> +#define HDPTX_I_BIAS_EN BIT(6)
>>>>> +#define HDPTX_I_BGR_EN BIT(5)
>>>>> +#define GRF_HDPTX_STATUS 0x80
>>>>> +#define HDPTX_O_PLL_LOCK_DONE BIT(3)
>>>>> +#define HDPTX_O_PHY_CLK_RDY BIT(2)
>>>>> +#define HDPTX_O_PHY_RDY BIT(1)
>>>>> +#define HDPTX_O_SB_RDY BIT(0)
>>>>> +
>>>>> +#define CMN_REG0000 0x0000
>>>>
>>>> These register names are not particularly helpful. Maybe use a
>>>>
>>>> #define CMN_REG(x) ((x) * 4)
>>>>
>>>> Instead?
>>>
>>> Yes, sounds good.
>>>
>>>>> +
>>>>> +static int hdptx_lcpll_frl_mode_config(struct rockchip_hdptx_phy *hdptx,
>>>>> + u32 rate)
>>>>> +{
>>>>> + u32 bit_rate = rate & DATA_RATE_MASK;
>>>>> + u8 color_depth = (rate & COLOR_DEPTH_MASK) ? 1 : 0;
>>>>> + const struct lcpll_config *cfg = lcpll_cfg;
>>>>> +
>>>>> + for (; cfg->bit_rate != ~0; cfg++)
>>>>> + if (bit_rate == cfg->bit_rate)
>>>>> + break;
>>>>
>>>> You could use ARRAY_SIZE() to iterate over the array and save the extra
>>>> entry at the end. Likewise for the other arrays used in the driver.
>>>
>>> Sure, will do.
>>>
>>>>> +
>>>>> + if (cfg->bit_rate == ~0)
>>>>> + return -EINVAL;
>>>>> +
>>>>
>>>>> +static int rockchip_hdptx_phy_power_on(struct phy *phy)
>>>>> +{
>>>>> + struct rockchip_hdptx_phy *hdptx = phy_get_drvdata(phy);
>>>>> + int bus_width = phy_get_bus_width(hdptx->phy);
>>>>> + int bit_rate = bus_width & DATA_RATE_MASK;
>>>>
>>>> What is going on here? bus_width is set to 8 in probe() using
>>>> phy_set_bus_width(), but the value you pull out of phy_get_bus_width()
>>>> is expected to contain the bit_rate and several other flags.
>>>>
>>>> It looks like you are tunneling flags from some other driver using this
>>>> field. Isn't there a better way to accomplish this? If not, I think this
>>>> needs some explanation.
>>>
>>> Indeed, sorry for missing a comment here. The flags are set by the
>>> bridge driver to enable 10-bit color depth, FRL and EARC. So far I
>>> couldn't find an alternative approach to pass custom data using the PHY API.
>>>
>>>> At least the variable should be renamed. it's called "bus_width" and it's
>>>> passed to functions like hdptx_lcpll_frl_mode_config() which has this
>>>> parameter named "rate" which is quite confusing.
>>>
>>> I think for the initial support it's not really necessary to implement
>>> all those features. Andy, should we drop them until a better solution
>>> is found?
>
> How about add a PHY_MODE_HDMI to enum phy_mode, and pass this custom data by extend phy_configure_opts
> or the submode of phy_set_mode_ext ?
Please see the patch "phy: Add HDMI configuration options" [1] from
Sandor Yu. Also the series "drm/connector: Create HDMI Connector
infrastructure" [2] from Maxime Ripard may be of interest.
[1] https://lore.kernel.org/all/19070c125268cfe900021dea6e7e8379b89c630e.1704785836.git.Sandor.yu@nxp.com/
[2] https://lore.kernel.org/dri-devel/20231207-kms-hdmi-connector-state-v5-0-6538e19d634d@kernel.org/
Regards,
Jonas
>>
>> I'm fine with it.
>> It would be very appreciated if some linux-phy or drm bridge experts can give
>> some suggestions about how to pass different custom phy modes.
>>
>>>
>>>> Sascha
>>>
>>> Thanks for the review,
>>> Cristian
More information about the Linux-rockchip
mailing list