Hi Roger, On 21/01/19 3:17 PM, Roger Quadros wrote: > Hi Kishon, > > On 21/01/19 08:48, Kishon Vijay Abraham I wrote: >> Add a new SERDES driver for TI's AM654x SoC which configures >> the SERDES only for PCIe. Support fo USB3 will be added later. >> >> SERDES in am654x has three input clocks (left input, externel reference >> clock and right input) and two output clocks (left output and right >> output) in addition to a PLL mux clock which the SERDES uses for Clock >> Multiplier Unit (CMU refclock). >> >> The PLL mux clock can select from one of the three input clocks. >> The right output can select between left input and external reference >> clock while the left output can select between the right input and >> external reference clock. >> >> The driver has support to select PLL mux and left/right output mux as >> specified in device tree. >> >> [rog...@ti.com: Fix boot lockup caused by accessing a structure member >> (hw->init) allocated in stack of probe() and accessed in get_parent] >> [rog...@ti.com: Fix "Failed to find the parent" warnings] >> Signed-off-by: Roger Quadros <rog...@ti.com> >> Signed-off-by: Kishon Vijay Abraham I <kis...@ti.com> >> --- >> drivers/phy/ti/Kconfig | 11 + >> drivers/phy/ti/Makefile | 1 + >> drivers/phy/ti/phy-am654-serdes.c | 528 ++++++++++++++++++++++++++++++ >> 3 files changed, 540 insertions(+) >> create mode 100644 drivers/phy/ti/phy-am654-serdes.c >> >> diff --git a/drivers/phy/ti/Kconfig b/drivers/phy/ti/Kconfig >> index f137e0107764..6357c32de115 100644 >> --- a/drivers/phy/ti/Kconfig >> +++ b/drivers/phy/ti/Kconfig >> @@ -20,6 +20,17 @@ config PHY_DM816X_USB >> help >> Enable this for dm816x USB to work. >> >> +config PHY_AM654_SERDES >> + tristate "TI AM654 SERDES support" >> + depends on OF && ARCH_K3 || COMPILE_TEST >> + select GENERIC_PHY >> + select MULTIPLEXER >> + select REGMAP_MMIO >> + select MUX_MMIO >> + help >> + This option enables support for TI AM654 SerDes PHY used for >> + PCIe. >> + >> config OMAP_CONTROL_PHY >> tristate "OMAP CONTROL PHY Driver" >> depends on ARCH_OMAP2PLUS || COMPILE_TEST >> diff --git a/drivers/phy/ti/Makefile b/drivers/phy/ti/Makefile >> index bea8f25a137a..bff901eb0ecc 100644 >> --- a/drivers/phy/ti/Makefile >> +++ b/drivers/phy/ti/Makefile >> @@ -6,4 +6,5 @@ obj-$(CONFIG_OMAP_USB2) += >> phy-omap-usb2.o >> obj-$(CONFIG_TI_PIPE3) += phy-ti-pipe3.o >> obj-$(CONFIG_PHY_TUSB1210) += phy-tusb1210.o >> obj-$(CONFIG_TWL4030_USB) += phy-twl4030-usb.o >> +obj-$(CONFIG_PHY_AM654_SERDES) += phy-am654-serdes.o >> obj-$(CONFIG_PHY_TI_GMII_SEL) += phy-gmii-sel.o >> diff --git a/drivers/phy/ti/phy-am654-serdes.c >> b/drivers/phy/ti/phy-am654-serdes.c >> new file mode 100644 >> index 000000000000..fcc0a98fbbd3 >> --- /dev/null >> +++ b/drivers/phy/ti/phy-am654-serdes.c >> @@ -0,0 +1,528 @@ >> +// SPDX-License-Identifier: GPL-2.0 >> +/** >> + * PCIe SERDES driver for AM654x SoC >> + * >> + * Copyright (C) 2018 Texas Instruments >> + * Author: Kishon Vijay Abraham I <kis...@ti.com> >> + */ >> + >> +#include <dt-bindings/phy/phy.h> >> +#include <linux/clk.h> >> +#include <linux/clk-provider.h> >> +#include <linux/delay.h> >> +#include <linux/io.h> >> +#include <linux/module.h> >> +#include <linux/mux/consumer.h> >> +#include <linux/of_address.h> >> +#include <linux/of_device.h> >> +#include <linux/phy/phy.h> >> +#include <linux/platform_device.h> >> +#include <linux/pm_runtime.h> >> +#include <linux/regmap.h> >> +#include <linux/slab.h> >> +#include <linux/mfd/syscon.h> >> + >> +#define CMU_R07C 0x7c >> +#define CMU_MASTER_CDN_O BIT(24) >> + >> +#define COMLANE_R138 0xb38 >> +#define CONFIG_VERSION_REG_MASK GENMASK(23, 16) >> +#define CONFIG_VERSION_REG_SHIFT 16 >> +#define VERSION 0x70 >> + >> +#define COMLANE_R190 0xb90 >> +#define L1_MASTER_CDN_O BIT(9) >> + >> +#define COMLANE_R194 0xb94 >> +#define CMU_OK_I_0 BIT(19) >> + >> +#define SERDES_CTRL 0x1fd0 >> +#define POR_EN BIT(29) >> + >> +#define WIZ_LANEXCTL_STS 0x1fe0 >> +#define TX0_ENABLE_OVL BIT(31) >> +#define TX0_ENABLE_MASK GENMASK(30, 29) >> +#define TX0_ENABLE_SHIFT 29 >> +#define TX0_DISABLE_STATE 0x0 >> +#define TX0_SLEEP_STATE 0x1 >> +#define TX0_SNOOZE_STATE 0x2 >> +#define TX0_ENABLE_STATE 0x3 >> +#define RX0_ENABLE_OVL BIT(15) >> +#define RX0_ENABLE_MASK GENMASK(14, 13) >> +#define RX0_ENABLE_SHIFT 13 >> +#define RX0_DISABLE_STATE 0x0 >> +#define RX0_SLEEP_STATE 0x1 >> +#define RX0_SNOOZE_STATE 0x2 >> +#define RX0_ENABLE_STATE 0x3 >> + >> +#define WIZ_PLL_CTRL 0x1ff4 >> +#define PLL_ENABLE_OVL BIT(31) >> +#define PLL_ENABLE_MASK GENMASK(30, 29) >> +#define PLL_ENABLE_SHIFT 29 >> +#define PLL_DISABLE_STATE 0x0 >> +#define PLL_SLEEP_STATE 0x1 >> +#define PLL_SNOOZE_STATE 0x2 >> +#define PLL_ENABLE_STATE 0x3 >> +#define PLL_OK BIT(28) >> + >> +#define PLL_LOCK_TIME 100000 /* in microseconds */ >> +#define SLEEP_TIME 100 /* in microseconds */ >> + >> +#define LANE_USB3 0x0 >> +#define LANE_PCIE0_LANE0 0x1 >> + >> +#define LANE_PCIE1_LANE0 0x0 >> +#define LANE_PCIE0_LANE1 0x1 >> + >> +#define SERDES_NUM_CLOCKS 3 >> + >> +struct serdes_am654_clk_mux { >> + struct clk_hw hw; >> + struct regmap *regmap; >> + unsigned int reg; >> + int *table; >> + u32 mask; >> + u8 shift; >> + struct clk_init_data clk_data; >> +}; >> + >> +#define to_serdes_am654_clk_mux(_hw) \ >> + container_of(_hw, struct serdes_am654_clk_mux, hw) >> + >> +static struct regmap_config serdes_am654_regmap_config = { >> + .reg_bits = 32, >> + .val_bits = 32, >> + .reg_stride = 4, >> + .fast_io = true, >> +}; >> + >> +struct serdes_am654 { >> + struct regmap *regmap; >> + struct device *dev; >> + struct mux_control *control; >> + bool busy; >> + u32 type; >> + struct device_node *of_node; >> + struct clk_onecell_data clk_data; >> + struct clk *clks[SERDES_NUM_CLOCKS]; >> +}; >> + >> +static int serdes_am654_enable_pll(struct serdes_am654 *phy) >> +{ >> + u32 mask = PLL_ENABLE_OVL | PLL_ENABLE_MASK; >> + u32 val = PLL_ENABLE_OVL | (PLL_ENABLE_STATE << PLL_ENABLE_SHIFT); >> + >> + regmap_update_bits(phy->regmap, WIZ_PLL_CTRL, mask, val); >> + >> + return regmap_read_poll_timeout(phy->regmap, WIZ_PLL_CTRL, val, >> + val & PLL_OK, 1000, PLL_LOCK_TIME); >> +} >> + >> +static void serdes_am654_disable_pll(struct serdes_am654 *phy) >> +{ >> + u32 mask = PLL_ENABLE_OVL | PLL_ENABLE_MASK; >> + >> + regmap_update_bits(phy->regmap, WIZ_PLL_CTRL, mask, 0); > > Shouldn't PLL_ENABLE_OVL be left set otherwise override mechanism won't work?
I have to check this. > > So, > > regmap_update_bits(phy->regmap, WIZ_PLL_CTRL, mask, PLL_ENABLE_OVL); > >> +} >> + >> +static int serdes_am654_enable_txrx(struct serdes_am654 *phy) >> +{ >> + u32 mask; >> + u32 val; >> + >> + /* Enable TX */ >> + mask = TX0_ENABLE_OVL | TX0_ENABLE_MASK; >> + val = TX0_ENABLE_OVL | (TX0_ENABLE_STATE << TX0_ENABLE_SHIFT); >> + regmap_update_bits(phy->regmap, WIZ_LANEXCTL_STS, mask, val); >> + >> + /* Enable RX */ >> + mask = RX0_ENABLE_OVL | RX0_ENABLE_MASK; >> + val = RX0_ENABLE_OVL | (RX0_ENABLE_STATE << RX0_ENABLE_SHIFT); >> + regmap_update_bits(phy->regmap, WIZ_LANEXCTL_STS, mask, val); >> + >> + return 0; >> +} >> + >> +static int serdes_am654_disable_txrx(struct serdes_am654 *phy) >> +{ >> + u32 mask; >> + >> + /* Disable TX */ >> + mask = TX0_ENABLE_OVL | TX0_ENABLE_MASK; >> + regmap_update_bits(phy->regmap, WIZ_LANEXCTL_STS, mask, 0); > > Here too. >> + >> + /* Disable RX */ >> + mask = RX0_ENABLE_OVL | RX0_ENABLE_MASK; >> + regmap_update_bits(phy->regmap, WIZ_LANEXCTL_STS, mask, 0); > > Here as well. > >> + >> + return 0; >> +} >> + >> +static int serdes_am654_power_on(struct phy *x) >> +{ >> + struct serdes_am654 *phy = phy_get_drvdata(x); >> + struct device *dev = phy->dev; >> + int ret; >> + u32 val; >> + >> + ret = serdes_am654_enable_pll(phy); >> + if (ret) { >> + dev_err(dev, "Failed to enable PLL\n"); >> + return ret; >> + } >> + >> + ret = serdes_am654_enable_txrx(phy); >> + if (ret) { >> + dev_err(dev, "Failed to enable TX RX\n"); >> + return ret; >> + } >> + >> + return regmap_read_poll_timeout(phy->regmap, COMLANE_R194, val, >> + val & CMU_OK_I_0, SLEEP_TIME, >> + PLL_LOCK_TIME); >> +} >> + >> +static int serdes_am654_power_off(struct phy *x) >> +{ >> + struct serdes_am654 *phy = phy_get_drvdata(x); >> + >> + serdes_am654_disable_txrx(phy); >> + serdes_am654_disable_pll(phy); >> + >> + return 0; >> +} >> + >> +static int serdes_am654_init(struct phy *x) >> +{ >> + struct serdes_am654 *phy = phy_get_drvdata(x); >> + u32 mask; >> + u32 val; >> + >> + mask = CONFIG_VERSION_REG_MASK; >> + val = VERSION << CONFIG_VERSION_REG_SHIFT; >> + regmap_update_bits(phy->regmap, COMLANE_R138, mask, val); >> + >> + val = CMU_MASTER_CDN_O; >> + regmap_update_bits(phy->regmap, CMU_R07C, val, val); >> + >> + val = L1_MASTER_CDN_O; >> + regmap_update_bits(phy->regmap, COMLANE_R190, val, val); >> + >> + return 0; >> +} >> + >> +static int serdes_am654_reset(struct phy *x) >> +{ >> + struct serdes_am654 *phy = phy_get_drvdata(x); >> + u32 val; >> + >> + val = POR_EN; >> + regmap_update_bits(phy->regmap, SERDES_CTRL, val, val); >> + mdelay(1); >> + regmap_update_bits(phy->regmap, SERDES_CTRL, val, 0); >> + >> + return 0; >> +} >> + >> +struct phy *serdes_am654_xlate(struct device *dev, struct of_phandle_args >> + *args) >> +{ >> + struct serdes_am654 *am654_phy; >> + struct phy *phy; >> + int ret; >> + >> + phy = of_phy_simple_xlate(dev, args); >> + if (IS_ERR(phy)) >> + return phy; >> + >> + am654_phy = phy_get_drvdata(phy); >> + if (am654_phy->type != args->args[0] && am654_phy->busy) >> + return ERR_PTR(-EBUSY); > > You set the busy flag in this function but it is never cleared. > This means the second phy_get() will always fail. We might get into this > situation for example if the driver doing the phy_get() had to bail out > due to some reason (e.g. -EPROBE_DEFER), and gets probed again and does > a phy_get() a second time for the same PHY and lane. > > Can we clear the busy flag and call mux_control_deselect() on phy_put()? Good point. Right now, the PHY framework doesn't have a callback to the PHY drivers on phy_put. Looks like we might have to add it for this scenario. Thanks Kishon