[PATCH 1/6 v4] serial: qcom: add support for GENI serial driver

Simon Glass sjg at chromium.org
Thu Oct 14 17:09:58 CEST 2021


Hi Dzmitry,

On Fri, 8 Oct 2021 at 00:46, Dzmitry Sankouski <dsankouski at gmail.com> wrote:
>
> Generic Interface (GENI) Serial Engine (SE) based uart
> can be found on newer qualcomm SOCs, starting from SDM845.
> Tested on Samsung SM-G9600(starqltechn)
> by chain-loading u-boot with stock bootloader.
>
> Signed-off-by: Dzmitry Sankouski <dsankouski at gmail.com>
> Cc: Ramon Fried <rfried.dev at gmail.com>
> Cc: Tom Rini <trini at konsulko.com>
> ---
> Changes for v2:
> - change functions return type to void, where possible
> - remove '.' from summary line
> Changes for v3:
> - move function open brace on new line
> - use tab between define name and value
> - define: wrap expression with braces, remove braces from constants
> Changes for v4:
> - add linux/delay.h header
>
>  MAINTAINERS                                   |   1 +
>  .../serial/msm-geni-serial.txt                |   6 +
>  drivers/serial/Kconfig                        |  17 +
>  drivers/serial/Makefile                       |   1 +
>  drivers/serial/serial_msm_geni.c              | 603 ++++++++++++++++++
>  5 files changed, 628 insertions(+)
>  create mode 100644 doc/device-tree-bindings/serial/msm-geni-serial.txt
>  create mode 100644 drivers/serial/serial_msm_geni.c

Reviewed-by: Simon Glass <sjg at chromium.org>

Some nits below

>
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 776ff703b9..52ddc99cda 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -390,6 +390,7 @@ F:  drivers/gpio/msm_gpio.c
>  F:     drivers/mmc/msm_sdhci.c
>  F:     drivers/phy/msm8916-usbh-phy.c
>  F:     drivers/serial/serial_msm.c
> +F:     drivers/serial/serial_msm_geni.c
>  F:     drivers/smem/msm_smem.c
>  F:     drivers/usb/host/ehci-msm.c
>
> diff --git a/doc/device-tree-bindings/serial/msm-geni-serial.txt b/doc/device-tree-bindings/serial/msm-geni-serial.txt
> new file mode 100644
> index 0000000000..9eadc2561b
> --- /dev/null
> +++ b/doc/device-tree-bindings/serial/msm-geni-serial.txt
> @@ -0,0 +1,6 @@
> +Qualcomm GENI UART
> +
> +Required properties:
> +- compatible: must be "qcom,msm-geni-uart"
> +- reg: start address and size of the registers
> +- clock: interface clock (must accept baudrate as a frequency)
> diff --git a/drivers/serial/Kconfig b/drivers/serial/Kconfig
> index 93348c0929..b420a5720d 100644
> --- a/drivers/serial/Kconfig
> +++ b/drivers/serial/Kconfig
> @@ -278,6 +278,14 @@ config DEBUG_UART_S5P
>           will need to provide parameters to make this work. The driver will
>           be available until the real driver-model serial is running.
>
> +config DEBUG_UART_MSM_GENI

Do you need this? Most drivers just use the existing DEBUG_UART Kconfig.

> +       bool "Qualcomm snapdragon"
> +       depends on ARCH_SNAPDRAGON
> +       help
> +         Select this to enable a debug UART using the serial_msm driver. You
> +         will need to provide parameters to make this work. The driver will
> +         be available until the real driver-model serial is running.
> +
>  config DEBUG_UART_MESON
>         bool "Amlogic Meson"
>         depends on MESON_SERIAL
> @@ -783,6 +791,15 @@ config MSM_SERIAL
>           for example APQ8016 and MSM8916.
>           Single baudrate is supported in current implementation (115200).
>
> +config MSM_GENI_SERIAL
> +       bool "Qualcomm on-chip GENI UART"
> +       help
> +         Support UART based on Generic Interface (GENI) Serial Engine (SE), used on Qualcomm Snapdragon SoCs.
> +         Should support all qualcomm SOCs with Qualcomm Universal Peripheral (QUP) Wrapper cores,

80cols

> +         i.e. newer ones, starting from SDM845.
> +         Driver works in FIFO mode.
> +         Multiple baudrates supported.
> +
>  config OCTEON_SERIAL_BOOTCMD
>         bool "MIPS Octeon PCI remote bootcmd input"
>         depends on ARCH_OCTEON
> diff --git a/drivers/serial/Makefile b/drivers/serial/Makefile
> index 3cbea8156f..d44caf4ea2 100644
> --- a/drivers/serial/Makefile
> +++ b/drivers/serial/Makefile
> @@ -62,6 +62,7 @@ obj-$(CONFIG_PIC32_SERIAL) += serial_pic32.o
>  obj-$(CONFIG_BCM283X_MU_SERIAL) += serial_bcm283x_mu.o
>  obj-$(CONFIG_BCM283X_PL011_SERIAL) += serial_bcm283x_pl011.o
>  obj-$(CONFIG_MSM_SERIAL) += serial_msm.o
> +obj-$(CONFIG_MSM_GENI_SERIAL) += serial_msm_geni.o
>  obj-$(CONFIG_MVEBU_A3700_UART) += serial_mvebu_a3700.o
>  obj-$(CONFIG_MPC8XX_CONS) += serial_mpc8xx.o
>  obj-$(CONFIG_NULLDEV_SERIAL) += serial_nulldev.o
> diff --git a/drivers/serial/serial_msm_geni.c b/drivers/serial/serial_msm_geni.c
> new file mode 100644
> index 0000000000..c656d54cbb
> --- /dev/null
> +++ b/drivers/serial/serial_msm_geni.c
> @@ -0,0 +1,603 @@
> +// SPDX-License-Identifier: GPL-2.0+
> +/*
> + * Qualcomm GENI serial engine UART driver
> + *
> + * (C) Copyright 2021 Dzmitry Sankouski <dsankouski at gmail.com>
> + *
> + * Based on Linux driver.
> + */
> +
> +#include <asm/io.h>
> +#include <clk.h>
> +#include <common.h>
> +#include <dm.h>
> +#include <dm/pinctrl.h>
> +#include <errno.h>
> +#include <linux/compiler.h>
> +#include <log.h>
> +#include <linux/delay.h>
> +#include <malloc.h>
> +#include <serial.h>
> +#include <watchdog.h>
> +
> +#define UART_OVERSAMPLING      32
> +#define STALE_TIMEOUT  160
> +#define SE_UART_RX_STALE_CNT   0x294
> +#define S_GENI_CMD_ABORT       (BIT(1))
> +
> +#define SE_GENI_S_CMD_CTRL_REG 0x634
> +#define SE_GENI_M_CMD_CTRL_REG 0x604
> +
> +/* GENI_M_CMD_CTRL_REG */
> +#define M_GENI_CMD_CANCEL      (BIT(2))
> +#define M_GENI_CMD_ABORT       (BIT(1))
> +#define M_GENI_DISABLE (BIT(0))
> +
> +/* GENI_S_CMD0 fields */
> +#define S_OPCODE_MSK   (GENMASK(31, 27))
> +#define S_OPCODE_SHFT  27
> +#define S_PARAMS_MSK   (GENMASK(26, 0))
> +
> +/* GENI_STATUS fields */
> +#define M_GENI_CMD_ACTIVE      (BIT(0))
> +#define S_GENI_CMD_ACTIVE      (BIT(12))
> +#define S_CMD_DONE_EN  (BIT(0))
> +#define M_CMD_DONE_EN  (BIT(0))
> +
> +#define USEC_PER_SEC   1000000L
> +
> +#define SE_GENI_STATUS 0x40
> +#define GENI_SER_M_CLK_CFG     0x48
> +#define GENI_SER_S_CLK_CFG     0x4C
> +#define SE_GENI_M_CMD0 0x600
> +#define SE_GENI_M_IRQ_CLEAR    0x618
> +#define SE_GENI_S_IRQ_STATUS   0x640
> +#define SE_GENI_S_IRQ_CLEAR    0x648
> +#define SE_GENI_S_IRQ_EN       0x644
> +#define SE_GENI_M_IRQ_EN       0x614
> +#define SE_GENI_TX_FIFOn       0x700
> +#define SE_GENI_RX_FIFOn       0x780
> +#define SE_GENI_TX_FIFO_STATUS 0x800
> +#define SE_GENI_RX_FIFO_STATUS 0x804
> +#define SE_GENI_TX_WATERMARK_REG       0x80C
> +#define M_TX_FIFO_WATERMARK_EN (BIT(30))
> +#define DEF_TX_WM      2
> +#define SE_UART_TX_TRANS_LEN   0x270
> +#define SE_GENI_TX_PACKING_CFG0        0x260
> +#define SE_GENI_TX_PACKING_CFG1        0x264
> +#define SE_GENI_RX_PACKING_CFG0        0x284
> +#define SE_GENI_RX_PACKING_CFG1        0x288
> +#define SE_UART_TX_STOP_BIT_LEN        0x26c
> +#define SE_UART_TX_WORD_LEN    0x268
> +#define SE_UART_RX_WORD_LEN    0x28c
> +#define SE_UART_RX_TRANS_CFG   0x280
> +#define SE_UART_RX_PARITY_CFG  0x2a8
> +#define SE_UART_TX_TRANS_CFG   0x25c
> +#define SE_UART_TX_PARITY_CFG  0x2a4
> +
> +#define GENI_FORCE_DEFAULT_REG 0x20
> +/* GENI_FORCE_DEFAULT_REG fields */
> +#define FORCE_DEFAULT  (BIT(0))
> +
> +#define S_CMD_ABORT_EN (BIT(5))
> +
> +#define SE_GENI_S_CMD0 0x630
> +#define UART_START_READ        0x1
> +
> +/* GENI_M_CMD_CTRL_REG */
> +#define M_GENI_CMD_CANCEL      (BIT(2))
> +#define M_GENI_CMD_ABORT       (BIT(1))
> +#define M_GENI_DISABLE (BIT(0))
> +
> +#define M_CMD_ABORT_EN (BIT(5))
> +
> +#define M_CMD_DONE_EN  (BIT(0))
> +#define M_CMD_DONE_DISABLE_MASK        (~M_CMD_DONE_EN)
> +#define SE_GENI_M_IRQ_STATUS   0x610
> +
> +#define M_OPCODE_SHIFT 27
> +#define S_OPCODE_SHIFT 27
> +#define M_TX_FIFO_WATERMARK_EN (BIT(30))
> +#define UART_START_TX  0x1
> +#define UART_CTS_MASK  (BIT(1))
> +#define M_SEC_IRQ_EN   (BIT(31))
> +#define TX_FIFO_WC_MSK (GENMASK(27, 0))
> +#define RX_FIFO_WC_MSK (GENMASK(24, 0))
> +
> +#define S_RX_FIFO_WATERMARK_EN (BIT(26))
> +#define S_RX_FIFO_LAST_EN      (BIT(27))
> +#define M_RX_FIFO_WATERMARK_EN (BIT(26))
> +#define M_RX_FIFO_LAST_EN      (BIT(27))
> +
> +/* GENI_SER_M_CLK_CFG/GENI_SER_S_CLK_CFG */
> +#define SER_CLK_EN     (BIT(0))
> +#define CLK_DIV_MSK    (GENMASK(15, 4))
> +#define CLK_DIV_SHFT   4
> +
> +#define SE_HW_PARAM_0  0xE24
> +/* SE_HW_PARAM_0 fields */
> +#define TX_FIFO_WIDTH_MSK      (GENMASK(29, 24))
> +#define TX_FIFO_WIDTH_SHFT     24
> +#define TX_FIFO_DEPTH_MSK      (GENMASK(21, 16))
> +#define TX_FIFO_DEPTH_SHFT     16
> +
> +DECLARE_GLOBAL_DATA_PTR;
> +
> +struct msm_serial_data {
> +       phys_addr_t base;
> +       u32 baud;
> +};
> +
> +static int get_clk_cfg(unsigned long clk_freq, unsigned long *ser_clk)

function comment...what does it return?

> +{
> +       unsigned long root_freq[] = {7372800,  14745600, 19200000, 29491200,
> +                                    32000000, 48000000, 64000000, 80000000,
> +                                    96000000, 100000000};
> +       int i;
> +       int match = -1;
> +
> +       for (i = 0; i < ARRAY_SIZE(root_freq); i++) {
> +               if (clk_freq > root_freq[i])
> +                       continue;
> +
> +               if (!(root_freq[i] % clk_freq)) {
> +                       match = i;
> +                       break;
> +               }
> +       }
> +       if (match != -1)
> +               *ser_clk = root_freq[match];
> +       else
> +               pr_err("clk_freq %ld\n", clk_freq);
> +       return match;
> +}
> +
> +static int get_clk_div_rate(u32 baud, u64 *desired_clk_rate)

function comment

> +{
> +       unsigned long ser_clk;
> +       int dfs_index;
> +       int clk_div = 0;
> +
> +       *desired_clk_rate = baud * UART_OVERSAMPLING;
> +       dfs_index = get_clk_cfg(*desired_clk_rate, &ser_clk);
> +       if (dfs_index < 0) {
> +               pr_err("%s: Can't find matching DFS entry for baud %d\n",
> +                      __func__, baud);
> +               clk_div = -EINVAL;
> +               goto exit_get_clk_div_rate;
> +       }
> +
> +       clk_div = ser_clk / *desired_clk_rate;
> +       *desired_clk_rate = ser_clk;
> +exit_get_clk_div_rate:
> +       return clk_div;
> +}
> +
> +static int geni_serial_set_clock_rate(struct udevice *dev, u64 rate)
> +{
> +       struct clk *clk;
> +       int ret;
> +
> +       clk = devm_clk_get(dev, "se-clk");
> +       if (!clk)
> +               return -EINVAL;
> +
> +       ret = clk_set_rate(clk, rate);
> +       return ret;
> +}
> +
> +/**
> + * geni_se_get_tx_fifo_depth() - Get the TX fifo depth of the serial engine
> + * @base:      Pointer to the concerned serial engine.
> + *
> + * This function is used to get the depth i.e. number of elements in the
> + * TX fifo of the serial engine.
> + *
> + * Return: TX fifo depth in units of FIFO words.
> + */
> +static inline u32 geni_se_get_tx_fifo_depth(long base)
> +{
> +       u32 tx_fifo_depth;
> +
> +       tx_fifo_depth = ((readl(base + SE_HW_PARAM_0) & TX_FIFO_DEPTH_MSK) >>
> +                        TX_FIFO_DEPTH_SHFT);
> +       return tx_fifo_depth;
> +}
> +
> +/**
> + * geni_se_get_tx_fifo_width() - Get the TX fifo width of the serial engine
> + * @base:      Pointer to the concerned serial engine.
> + *
> + * This function is used to get the width i.e. word size per element in the
> + * TX fifo of the serial engine.
> + *
> + * Return: TX fifo width in bits
> + */
> +static inline u32 geni_se_get_tx_fifo_width(long base)
> +{
> +       u32 tx_fifo_width;
> +
> +       tx_fifo_width = ((readl(base + SE_HW_PARAM_0) & TX_FIFO_WIDTH_MSK) >>
> +                        TX_FIFO_WIDTH_SHFT);
> +       return tx_fifo_width;
> +}
> +
> +static inline void geni_serial_baud(phys_addr_t base_address, u64 uclk,
> +                                                                       int baud)
> +{
> +       u32 clk_div;
> +       u32 s_clk_cfg = 0;
> +
> +       clk_div = get_clk_div_rate(baud, &uclk);
> +
> +       s_clk_cfg |= SER_CLK_EN;
> +       s_clk_cfg |= (clk_div << CLK_DIV_SHFT);
> +
> +       writel(s_clk_cfg, base_address + GENI_SER_M_CLK_CFG);
> +       writel(s_clk_cfg, base_address + GENI_SER_S_CLK_CFG);
> +}
> +
> +int msm_serial_setbrg(struct udevice *dev, int baud)
> +{
> +       struct msm_serial_data *priv = dev_get_priv(dev);
> +
> +       priv->baud = baud;
> +       u32 clk_div;
> +       u64 clk_rate;
> +
> +       clk_div = get_clk_div_rate(baud, &clk_rate);
> +       geni_serial_set_clock_rate(dev, clk_rate);
> +       geni_serial_baud(priv->base, clk_rate, baud);
> +
> +       return 0;
> +}
> +
> +static bool qcom_geni_serial_poll_bit(const struct udevice *dev, int offset,
> +                                     int field, bool set)

function comment

> +{
> +       u32 reg;
> +       struct msm_serial_data *priv = dev_get_priv(dev);
> +       unsigned int baud;
> +       unsigned int tx_fifo_depth;
> +       unsigned int tx_fifo_width;
> +       unsigned int fifo_bits;
> +       unsigned long timeout_us = 10000;
> +
> +       baud = 115200;
> +
> +       if (priv) {
> +               baud = priv->baud;
> +               if (!baud)
> +                       baud = 115200;
> +               tx_fifo_depth = geni_se_get_tx_fifo_depth(priv->base);
> +               tx_fifo_width = geni_se_get_tx_fifo_width(priv->base);
> +               fifo_bits = tx_fifo_depth * tx_fifo_width;
> +               /*
> +                * Total polling iterations based on FIFO worth of bytes to be
> +                * sent at current baud. Add a little fluff to the wait.
> +                */
> +               timeout_us = ((fifo_bits * USEC_PER_SEC) / baud) + 500;
> +       }
> +
> +       /*
> +        * Use custom implementation instead of readl_poll_atomic since ktimer
> +        * is not ready at the time of early console.

This comment seems to relate only to Linux?

> +        */
> +       timeout_us = DIV_ROUND_UP(timeout_us, 10) * 10;
> +       while (timeout_us) {
> +               reg = readl(priv->base + offset);
> +               if ((bool)(reg & field) == set)
> +                       return true;
> +               udelay(10);
> +               timeout_us -= 10;
> +       }
> +       return false;
> +}
> +
> +static void qcom_geni_serial_setup_tx(u64 base, u32 xmit_size)
> +{
> +       u32 m_cmd;
> +
> +       writel(xmit_size, base + SE_UART_TX_TRANS_LEN);
> +       m_cmd = UART_START_TX << M_OPCODE_SHIFT;
> +       writel(m_cmd, base + SE_GENI_M_CMD0);
> +}
> +
> +static inline void qcom_geni_serial_poll_tx_done(const struct udevice *dev)
> +{
> +       struct msm_serial_data *priv = dev_get_priv(dev);
> +       int done = 0;
> +       u32 irq_clear = M_CMD_DONE_EN;
> +
> +       done = qcom_geni_serial_poll_bit(dev, SE_GENI_M_IRQ_STATUS,
> +                                        M_CMD_DONE_EN, true);
> +       if (!done) {
> +               writel(M_GENI_CMD_ABORT, priv->base + SE_GENI_M_CMD_CTRL_REG);
> +               irq_clear |= M_CMD_ABORT_EN;
> +               qcom_geni_serial_poll_bit(dev, SE_GENI_M_IRQ_STATUS,
> +                                         M_CMD_ABORT_EN, true);
> +       }
> +       writel(irq_clear, priv->base + SE_GENI_M_IRQ_CLEAR);
> +}
> +
> +static u32 qcom_geni_serial_tx_empty(u64 base)
> +{
> +       return !readl(base + SE_GENI_TX_FIFO_STATUS);
> +}
> +
> +/**
> + * geni_se_setup_s_cmd() - Setup the secondary sequencer
> + * @se:                Pointer to the concerned serial engine.
> + * @cmd:       Command/Operation to setup in the secondary sequencer.
> + * @params:    Parameter for the sequencer command.
> + *
> + * This function is used to configure the secondary sequencer with the
> + * command and its associated parameters.
> + */
> +static inline void geni_se_setup_s_cmd(u64 base, u32 cmd, u32 params)
> +{
> +       u32 s_cmd;
> +
> +       s_cmd = readl(base + SE_GENI_S_CMD0);
> +       s_cmd &= ~(S_OPCODE_MSK | S_PARAMS_MSK);
> +       s_cmd |= (cmd << S_OPCODE_SHFT);
> +       s_cmd |= (params & S_PARAMS_MSK);
> +       writel(s_cmd, base + SE_GENI_S_CMD0);
> +}
> +
> +static void qcom_geni_serial_start_tx(u64 base)
> +{
> +       u32 irq_en;
> +       u32 status;
> +
> +       status = readl(base + SE_GENI_STATUS);
> +       if (status & M_GENI_CMD_ACTIVE)
> +               return;
> +
> +       if (!qcom_geni_serial_tx_empty(base))
> +               return;
> +
> +       irq_en = readl(base + SE_GENI_M_IRQ_EN);
> +       irq_en |= M_TX_FIFO_WATERMARK_EN | M_CMD_DONE_EN;
> +
> +       writel(DEF_TX_WM, base + SE_GENI_TX_WATERMARK_REG);
> +       writel(irq_en, base + SE_GENI_M_IRQ_EN);
> +}
> +
> +static void qcom_geni_serial_start_rx(struct udevice *dev)
> +{
> +       u32 irq_en;
> +       u32 status;
> +       struct msm_serial_data *priv = dev_get_priv(dev);
> +
> +       status = readl(priv->base + SE_GENI_STATUS);
> +
> +       geni_se_setup_s_cmd(priv->base, UART_START_READ, 0);
> +
> +       irq_en = readl(priv->base + SE_GENI_S_IRQ_EN);
> +       irq_en |= S_RX_FIFO_WATERMARK_EN | S_RX_FIFO_LAST_EN;
> +       writel(irq_en, priv->base + SE_GENI_S_IRQ_EN);

setbits_le32() ?

> +
> +       irq_en = readl(priv->base + SE_GENI_M_IRQ_EN);
> +       irq_en |= M_RX_FIFO_WATERMARK_EN | M_RX_FIFO_LAST_EN;
> +       writel(irq_en, priv->base + SE_GENI_M_IRQ_EN);

here too

> +}
> +
> +static void msm_geni_serial_setup_rx(struct udevice *dev)
> +{
> +       u32 irq_clear = S_CMD_DONE_EN;
> +       u32 geni_s_irq_en;
> +       u32 geni_m_irq_en;
> +       u32 cfg0;
> +       u32 cfg1;
> +       struct msm_serial_data *priv = dev_get_priv(dev);
> +
> +       irq_clear |= S_CMD_ABORT_EN;
> +
> +       writel(S_GENI_CMD_ABORT, priv->base + SE_GENI_S_CMD_CTRL_REG);
> +       qcom_geni_serial_poll_bit(dev, SE_GENI_S_CMD_CTRL_REG, S_GENI_CMD_ABORT,
> +                                 false);
> +       writel(irq_clear, priv->base + SE_GENI_S_IRQ_CLEAR);
> +       writel(FORCE_DEFAULT, priv->base + GENI_FORCE_DEFAULT_REG);
> +
> +       cfg0 = 0xf;

What is this? Can we have #define/enum/comment?

> +       cfg1 = 0x0;
> +       writel(cfg0, priv->base + SE_GENI_RX_PACKING_CFG0);
> +       writel(cfg1, priv->base + SE_GENI_RX_PACKING_CFG1);
> +
> +       geni_se_setup_s_cmd(priv->base, UART_START_READ, 0);
> +
> +       geni_s_irq_en = readl(priv->base + SE_GENI_S_IRQ_EN);
> +       geni_m_irq_en = readl(priv->base + SE_GENI_M_IRQ_EN);
> +
> +       geni_s_irq_en |= S_RX_FIFO_WATERMARK_EN | S_RX_FIFO_LAST_EN;
> +       geni_m_irq_en |= M_RX_FIFO_WATERMARK_EN | M_RX_FIFO_LAST_EN;
> +
> +       writel(geni_s_irq_en, priv->base + SE_GENI_S_IRQ_EN);
> +       writel(geni_m_irq_en, priv->base + SE_GENI_M_IRQ_EN);
> +}
> +
> +static int msm_serial_putc(struct udevice *dev, const char ch)
> +{
> +       struct msm_serial_data *priv = dev_get_priv(dev);
> +
> +       writel(DEF_TX_WM, priv->base + SE_GENI_TX_WATERMARK_REG);
> +       qcom_geni_serial_setup_tx(priv->base, 1);
> +
> +       qcom_geni_serial_poll_bit(dev, SE_GENI_M_IRQ_STATUS,
> +                                 M_TX_FIFO_WATERMARK_EN, true);
> +
> +       writel(ch, priv->base + SE_GENI_TX_FIFOn);
> +       writel(M_TX_FIFO_WATERMARK_EN, priv->base + SE_GENI_M_IRQ_CLEAR);
> +
> +       qcom_geni_serial_poll_tx_done(dev);
> +
> +       return 0;
> +}
> +
> +static int msm_serial_getc(struct udevice *dev)
> +{
> +       struct msm_serial_data *priv = dev_get_priv(dev);
> +       u32 rx_fifo;
> +       u32 m_irq_status;
> +       u32 s_irq_status;
> +
> +       writel(1 << S_OPCODE_SHIFT, priv->base + SE_GENI_S_CMD0);
> +
> +       qcom_geni_serial_poll_bit(dev, SE_GENI_M_IRQ_STATUS, M_SEC_IRQ_EN,
> +                                 true);
> +
> +       m_irq_status = readl(priv->base + SE_GENI_M_IRQ_STATUS);
> +       s_irq_status = readl(priv->base + SE_GENI_S_IRQ_STATUS);
> +       writel(m_irq_status, priv->base + SE_GENI_M_IRQ_CLEAR);
> +       writel(s_irq_status, priv->base + SE_GENI_S_IRQ_CLEAR);
> +       qcom_geni_serial_poll_bit(dev, SE_GENI_RX_FIFO_STATUS, RX_FIFO_WC_MSK,
> +                                 true);
> +
> +       if (!readl(priv->base + SE_GENI_RX_FIFO_STATUS))
> +               return 0;
> +
> +       rx_fifo = readl(priv->base + SE_GENI_RX_FIFOn);
> +       return rx_fifo & 0xff;
> +}
> +
> +static int msm_serial_pending(struct udevice *dev, bool input)
> +{
> +       struct msm_serial_data *priv = dev_get_priv(dev);
> +
> +       if (input)
> +               return readl(priv->base + SE_GENI_RX_FIFO_STATUS) &
> +                      RX_FIFO_WC_MSK;
> +       else
> +               return readl(priv->base + SE_GENI_TX_FIFO_STATUS) &
> +                      TX_FIFO_WC_MSK;
> +
> +       return 0;
> +}
> +
> +static const struct dm_serial_ops msm_serial_ops = {
> +       .putc = msm_serial_putc,
> +       .pending = msm_serial_pending,
> +       .getc = msm_serial_getc,
> +       .setbrg = msm_serial_setbrg,
> +};
> +
> +static inline void geni_serial_init(phys_addr_t base_address)
> +{
> +       u32 tx_trans_cfg;
> +       u32 tx_parity_cfg = 0; /* Disable Tx Parity */
> +       u32 rx_trans_cfg = 0;
> +       u32 rx_parity_cfg = 0; /* Disable Rx Parity */
> +       u32 stop_bit_len = 0;  /* Default stop bit length - 1 bit */
> +       u32 bits_per_char;
> +
> +       /*
> +        * Ignore Flow control.
> +        * n = 8.
> +        */
> +       tx_trans_cfg = UART_CTS_MASK;
> +       bits_per_char = BITS_PER_BYTE;
> +
> +       u32 cfg0 = 0xf;
> +
> +       u32 cfg1 = 0x0;
> +
> +       /*
> +        * Make an unconditional cancel on the main sequencer to reset
> +        * it else we could end up in data loss scenarios.
> +        */
> +       writel(cfg0, base_address + SE_GENI_TX_PACKING_CFG0);
> +       writel(cfg1, base_address + SE_GENI_TX_PACKING_CFG1);
> +       writel(cfg0, base_address + SE_GENI_RX_PACKING_CFG0);
> +       writel(cfg1, base_address + SE_GENI_RX_PACKING_CFG1);
> +
> +       writel(tx_trans_cfg, base_address + SE_UART_TX_TRANS_CFG);
> +       writel(tx_parity_cfg, base_address + SE_UART_TX_PARITY_CFG);
> +       writel(rx_trans_cfg, base_address + SE_UART_RX_TRANS_CFG);
> +       writel(rx_parity_cfg, base_address + SE_UART_RX_PARITY_CFG);
> +       writel(bits_per_char, base_address + SE_UART_TX_WORD_LEN);
> +       writel(bits_per_char, base_address + SE_UART_RX_WORD_LEN);
> +       writel(stop_bit_len, base_address + SE_UART_TX_STOP_BIT_LEN);
> +}
> +
> +static int msm_serial_probe(struct udevice *dev)
> +{
> +       struct msm_serial_data *priv = dev_get_priv(dev);
> +
> +       /* No need to reinitialize the UART after relocation */
> +       if (gd->flags & GD_FLG_RELOC)
> +               return 0;
> +
> +       geni_serial_init(priv->base);
> +       msm_geni_serial_setup_rx(dev);
> +       qcom_geni_serial_start_rx(dev);
> +       qcom_geni_serial_start_tx(priv->base);
> +
> +       pinctrl_select_state(dev, "uart");

Does this not happen automatically with the correct pinctrl properties
in the devicetree?

> +
> +       return 0;
> +}
> +
> +static int msm_serial_ofdata_to_platdata(struct udevice *dev)
> +{
> +       struct msm_serial_data *priv = dev_get_priv(dev);
> +
> +       priv->base = dev_read_addr(dev);
> +       if (priv->base == FDT_ADDR_T_NONE)
> +               return -EINVAL;
> +
> +       return 0;
> +}
> +
> +static const struct udevice_id msm_serial_ids[] = {
> +       {.compatible = "qcom,msm-geni-uart"}, {}};
> +
> +U_BOOT_DRIVER(serial_msm_geni) = {
> +       .name = "serial_msm_geni",
> +       .id = UCLASS_SERIAL,
> +       .of_match = msm_serial_ids,
> +       .of_to_plat = msm_serial_ofdata_to_platdata,
> +       .priv_auto = sizeof(struct msm_serial_data),
> +       .probe = msm_serial_probe,
> +       .ops = &msm_serial_ops,
> +};
> +
> +#ifdef CONFIG_DEBUG_UART_MSM_GENI
> +
> +static struct msm_serial_data init_serial_data = {
> +       .base = CONFIG_DEBUG_UART_BASE
> +};
> +
> +/* Serial dumb device, to reuse driver code */
> +static struct udevice init_dev = {
> +       .priv_ = &init_serial_data,
> +};
> +
> +#include <debug_uart.h>
> +
> +static inline void _debug_uart_init(void)
> +{
> +       phys_addr_t base = CONFIG_DEBUG_UART_BASE;
> +
> +       geni_serial_init(base);
> +       geni_serial_baud(base, CONFIG_DEBUG_UART_CLOCK, CONFIG_BAUDRATE);
> +       qcom_geni_serial_start_tx(base);
> +}
> +
> +static inline void _debug_uart_putc(int ch)
> +{
> +       phys_addr_t base = CONFIG_DEBUG_UART_BASE;
> +
> +       writel(DEF_TX_WM, base + SE_GENI_TX_WATERMARK_REG);
> +       qcom_geni_serial_setup_tx(base, 1);
> +       qcom_geni_serial_poll_bit(&init_dev, SE_GENI_M_IRQ_STATUS,
> +                                 M_TX_FIFO_WATERMARK_EN, true);
> +
> +       writel(ch, base + SE_GENI_TX_FIFOn);
> +       writel(M_TX_FIFO_WATERMARK_EN, base + SE_GENI_M_IRQ_CLEAR);
> +       qcom_geni_serial_poll_tx_done(&init_dev);
> +}
> +
> +DEBUG_UART_FUNCS
> +
> +#endif
> --
> 2.20.1
>

Regards,
Simon


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