Dear Andreas Wass,
The driver is ported from a driver that was implemented using u-boot 2009.
What driver? Anyway, this doesn't go here. If it's ported from LTIB, stick it into the file header in each file (see the other files , like the register definitions or so) for details.
The driver makes it possible to use a regular application UART as the U-Boot output console for MXS CPUs.
Signed-off-by: Andreas Wass andreas.wass@dalelven.com Cc: Fabio Estevam fabio.estevam@freescale.com Cc: Marek Vasut marex@denx.de
Changes for v2:
- Added comment that regs-uartapp.h is pulled from LTIB
- BM_ prefixes removed and _MASK suffixes added instead
- BP_ prefixes removed and _OFFSET suffixes added instead
- BF_ defines removed altogether
- CONFIG_MXS_AUART_CLK renamed to MXS_AUART_CLK and guarding ifndef
removed - Added comments describing what is set and unset during init of driver - Added newline that was accidently removed from serial.c
Nitpicks follow.
arch/arm/include/asm/arch-mxs/regs-uartapp.h | 236 +++++++++++++++++++++++++++ drivers/serial/Makefile | 1 + drivers/serial/mxs_auart.c | 139 ++++++++++++++++ drivers/serial/serial.c | 2 + 4 files changed, 378 insertions(+) create mode 100644 arch/arm/include/asm/arch-mxs/regs-uartapp.h create mode 100644 drivers/serial/mxs_auart.c
diff --git a/arch/arm/include/asm/arch-mxs/regs-uartapp.h b/arch/arm/include/asm/arch-mxs/regs-uartapp.h new file mode 100644 index 0000000..60a0812 --- /dev/null +++ b/arch/arm/include/asm/arch-mxs/regs-uartapp.h @@ -0,0 +1,236 @@ +/*
- Freescale MXS UARTAPP Register Definitions
- Copyright (C) 2013 Andreas Wass andreas.wass@dalelven.com
- Based on code from LTIB:
- Copyright 2008-2010 Freescale Semiconductor, Inc. All Rights Reserved.
- SPDX-License-Identifier: GPL-2.0+
- */
+#ifndef __ARCH_ARM___MXS_UARTAPP_H +#define __ARCH_ARM___MXS_UARTAPP_H
+#include <asm/imx-common/regs-common.h>
+#ifndef __ASSEMBLY__ +struct mxs_uartapp_regs {
- mxs_reg_32(hw_uartapp_ctrl0)
- mxs_reg_32(hw_uartapp_ctrl1)
- mxs_reg_32(hw_uartapp_ctrl2)
- mxs_reg_32(hw_uartapp_linectrl)
- mxs_reg_32(hw_uartapp_linectrl2)
- mxs_reg_32(hw_uartapp_intr)
- mxs_reg_32(hw_uartapp_data)
- mxs_reg_32(hw_uartapp_stat)
- mxs_reg_32(hw_uartapp_debug)
- mxs_reg_32(hw_uartapp_version)
- mxs_reg_32(hw_uartapp_autobaud)
+}; +#endif
+#define UARTAPP_CTRL0_SFTRST_MASK (1 << 31) +#define UARTAPP_CTRL0_CLKGATE_MASK (1 << 30) +#define UARTAPP_CTRL0_RUN_MASK (1 << 29) +#define UARTAPP_CTRL0_RX_SOURCE_MASK (1 << 28) +#define UARTAPP_CTRL0_RXTO_ENABLE_MASK (1 << 27) +#define UARTAPP_CTRL0_RXTIMEOUT_OFFSET (1 << 4) +#define UARTAPP_CTRL0_RXTIMEOUT_MASK 0x07FF0000 +#define UARTAPP_CTRL0_XFER_COUNT_OFFSET 0 +#define UARTAPP_CTRL0_XFER_COUNT_MASK 0x0000FFFF
+#define UARTAPP_CTRL1_RSVD2_OFFSET 29 +#define UARTAPP_CTRL1_RSVD2_MASK 0xE0000000
+#define UARTAPP_CTRL1_RUN_MASK (1 << 28) +#define UARTAPP_CTRL1_RSVD1_OFFSET 16 +#define UARTAPP_CTRL1_RSVD1_MASK 0x0FFF0000
+#define UARTAPP_CTRL1_XFER_COUNT_OFFSET 0 +#define UARTAPP_CTRL1_XFER_COUNT_MASK 0x0000FFFF
+#define UARTAPP_CTRL2_INVERT_RTS_MASK (1 << 31) +#define UARTAPP_CTRL2_INVERT_CTS_MASK (1 << 30) +#define UARTAPP_CTRL2_INVERT_TX_MASK (1 << 29) +#define UARTAPP_CTRL2_INVERT_RX_MASK (1 << 28) +#define UARTAPP_CTRL2_RTS_SEMAPHORE_MASK (1 << 27) +#define UARTAPP_CTRL2_DMAONERR_MASK (1 << 26) +#define UARTAPP_CTRL2_TXDMAE_MASK (1 << 25) +#define UARTAPP_CTRL2_RXDMAE_MASK (1 << 24) +#define UARTAPP_CTRL2_RSVD2_MASK (1 << 23) +#define UARTAPP_CTRL2_RXIFLSEL_OFFSET 20 +#define UARTAPP_CTRL2_RXIFLSEL_MASK 0x00700000
+#define BV_UARTAPP_CTRL2_RXIFLSEL__NOT_EMPTY 0x0 +#define BV_UARTAPP_CTRL2_RXIFLSEL__ONE_QUARTER 0x1 +#define BV_UARTAPP_CTRL2_RXIFLSEL__ONE_HALF 0x2 +#define BV_UARTAPP_CTRL2_RXIFLSEL__THREE_QUARTERS 0x3 +#define BV_UARTAPP_CTRL2_RXIFLSEL__SEVEN_EIGHTHS 0x4 +#define BV_UARTAPP_CTRL2_RXIFLSEL__INVALID5 0x5 +#define BV_UARTAPP_CTRL2_RXIFLSEL__INVALID6 0x6 +#define BV_UARTAPP_CTRL2_RXIFLSEL__INVALID7 0x7
BV ... this needs fixing. It's usually defined as (val << something)
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diff --git a/drivers/serial/Makefile b/drivers/serial/Makefile index 697f2bb..4c45bfa 100644 --- a/drivers/serial/Makefile +++ b/drivers/serial/Makefile @@ -38,6 +38,7 @@ COBJS-$(CONFIG_SCIF_CONSOLE) += serial_sh.o COBJS-$(CONFIG_ZYNQ_SERIAL) += serial_zynq.o COBJS-$(CONFIG_BFIN_SERIAL) += serial_bfin.o COBJS-$(CONFIG_FSL_LPUART) += serial_lpuart.o +COBJS-$(CONFIG_MXS_AUART) += mxs_auart.o
ifndef CONFIG_SPL_BUILD COBJS-$(CONFIG_USB_TTY) += usbtty.o diff --git a/drivers/serial/mxs_auart.c b/drivers/serial/mxs_auart.c new file mode 100644 index 0000000..eaca6a4 --- /dev/null +++ b/drivers/serial/mxs_auart.c @@ -0,0 +1,139 @@ +/*
- Driver to use an application UART as console output for Freescale
- MXS devices.
Freescale i.MX23/i.MX28 AUART driver
- Copyright (C) 2013 Andreas Wass andreas.wass@dalelven.com
- SPDX-License-Identifier: GPL-2.0+
- */
+#include <common.h> +#include <asm/io.h> +#include <serial.h> +#include <linux/compiler.h> +#include <asm/arch/regs-base.h> +#include <asm/arch/regs-uartapp.h> +#include <asm/arch/sys_proto.h>
+DECLARE_GLOBAL_DATA_PTR;
+#ifndef CONFIG_MXS_AUART_BASE +#error "CONFIG_MXS_AUART_BASE must be set to the base UART to use" +#endif
+/* AUART clock always supplied by XTAL and always 24MHz */ +#define MXS_AUART_CLK 24000000
+static struct mxs_uartapp_regs *get_uartapp_registers(void) +{
- return (struct mxs_uartapp_regs*)CONFIG_MXS_AUART_BASE;
+}
+/**
- Sets the baud rate and settings.
- The settings are: 8 data bits, no parit and 1 stop bit.
- */
+void mxs_auart_setbrg(void) +{
- u32 div;
- u32 linectrl = 0;
- struct mxs_uartapp_regs *regs = get_uartapp_registers();
- /*
* From i.MX28 datasheet:* div is calculated by calculating UARTCLK*32/baudrate, rounded to int* div must be between 0xEC and 0x003FFFC0 inclusive* Lowest 6 bits of div goes in BAUD_DIVFRAC part of LINECTRL register* Next 16 bits goes in BAUD_DIVINT part of LINECTRL register*/- div = (MXS_AUART_CLK * 32) / CONFIG_BAUDRATE;
You're not checking the div value here.
- linectrl |= ((div & 0x3F) << UARTAPP_LINECTRL_BAUD_DIVFRAC_OFFSET)
& UARTAPP_LINECTRL_BAUD_DIVFRAC_MASK;- linectrl |= ((div >> 6) << UARTAPP_LINECTRL_BAUD_DIVINT_OFFSET)
& UARTAPP_LINECTRL_BAUD_DIVINT_MASK;- /* Word length: 8 bits */
- linectrl |= ((0x03) << UARTAPP_LINECTRL_WLEN_OFFSET)
& UARTAPP_LINECTRL_WLEN_MASK;
You should clean these three magic numbers above.
- /* Enable FIFOs. */
- linectrl |= UARTAPP_LINECTRL_FEN_MASK;
- /* Write above settings, no parity, 1 stop bit */
- writel(linectrl, ®s->hw_uartapp_linectrl);
+}
+int mxs_auart_init(void) +{
- struct mxs_uartapp_regs *regs = get_uartapp_registers();
- /* Reset everything */
- mxs_reset_block(®s->hw_uartapp_ctrl0_reg);
- /* Disable interrupts */
- writel(0, ®s->hw_uartapp_intr);
- /* Set baud rate and settings */
- serial_setbrg();
- /*
* Disable RTS and CTS,* use values in LINECTRL register instead of LINECTRL2*/
Won't this fit on one line ?
[...]