Hi Oleksandr, On 02/04/2024 14:05, Oleksandr Tyshchenko wrote: > > > From: Oleksandr Tyshchenko <[email protected]> > > Tested on i.MX 8M Mini only, but I guess, it should be > suitable for other i.MX8M* SoCs (those UART device tree nodes > contain "fsl,imx6q-uart" compatible string). Please use imperative mood in commit msg. I would mention also that you are adding macros that will be used by the runtime driver.
> > Signed-off-by: Oleksandr Tyshchenko <[email protected]> > --- > I selected the following configs for enabling early printk: > > CONFIG_EARLY_UART_CHOICE_IMX_UART=y > CONFIG_EARLY_UART_IMX_UART=y > CONFIG_EARLY_PRINTK=y > CONFIG_EARLY_UART_BASE_ADDRESS=0x30890000 > CONFIG_EARLY_PRINTK_INC="debug-imx-uart.inc" > --- > --- > xen/arch/arm/Kconfig.debug | 14 +++++ > xen/arch/arm/arm64/debug-imx-uart.inc | 38 ++++++++++++++ > xen/arch/arm/include/asm/imx-uart.h | 76 +++++++++++++++++++++++++++ > 3 files changed, 128 insertions(+) > create mode 100644 xen/arch/arm/arm64/debug-imx-uart.inc > create mode 100644 xen/arch/arm/include/asm/imx-uart.h > > diff --git a/xen/arch/arm/Kconfig.debug b/xen/arch/arm/Kconfig.debug > index eec860e88e..a15d08f214 100644 > --- a/xen/arch/arm/Kconfig.debug > +++ b/xen/arch/arm/Kconfig.debug > @@ -68,6 +68,16 @@ choice > provide the parameters for the i.MX LPUART rather than > selecting one of the platform specific options below > if > you know the parameters for the port. > + config EARLY_UART_CHOICE_IMX_UART > + select EARLY_UART_IMX_UART > + depends on ARM_64 > + bool "Early printk via i.MX UART" > + help > + Say Y here if you wish the early printk to direct > their Do not take example from surrounding code. help text should be indented by 2 tabs and 2 spaces here. > + output to a i.MX UART. You can use this option to > + provide the parameters for the i.MX UART rather than > + selecting one of the platform specific options below > if > + you know the parameters for the port. > config EARLY_UART_CHOICE_MESON > select EARLY_UART_MESON > depends on ARM_64 > @@ -199,6 +209,9 @@ config EARLY_UART_EXYNOS4210 > config EARLY_UART_IMX_LPUART > select EARLY_PRINTK > bool > +config EARLY_UART_IMX_UART > + select EARLY_PRINTK > + bool > config EARLY_UART_MESON > select EARLY_PRINTK > bool > @@ -304,6 +317,7 @@ config EARLY_PRINTK_INC > default "debug-cadence.inc" if EARLY_UART_CADENCE > default "debug-exynos4210.inc" if EARLY_UART_EXYNOS4210 > default "debug-imx-lpuart.inc" if EARLY_UART_IMX_LPUART > + default "debug-imx-uart.inc" if EARLY_UART_IMX_UART > default "debug-meson.inc" if EARLY_UART_MESON > default "debug-mvebu.inc" if EARLY_UART_MVEBU > default "debug-pl011.inc" if EARLY_UART_PL011 > diff --git a/xen/arch/arm/arm64/debug-imx-uart.inc > b/xen/arch/arm/arm64/debug-imx-uart.inc > new file mode 100644 > index 0000000000..27a68b1ed5 > --- /dev/null > +++ b/xen/arch/arm/arm64/debug-imx-uart.inc > @@ -0,0 +1,38 @@ > +/* SPDX-License-Identifier: GPL-2.0-or-later */ > +/* > + * xen/arch/arm/arm64/debug-imx-uart.inc > + * > + * i.MX8M* specific debug code > + * > + * Copyright (C) 2024 EPAM Systems Inc. > + */ > + > +#include <asm/imx-uart.h> > + > +/* > + * Wait UART to be ready to transmit > + * rb: register which contains the UART base address > + * rc: scratch register > + */ > +.macro early_uart_ready xb, c > +1: > + ldr w\c, [\xb, #IMX21_UTS] /* <- Test register */ > + tst w\c, #UTS_TXFULL /* Check TxFIFO FULL bit */ > + bne 1b /* Wait for the UART to be ready */ > +.endm > + > +/* > + * UART transmit character > + * rb: register which contains the UART base address > + * rt: register which contains the character to transmit > + */ > +.macro early_uart_transmit xb, wt > + str \wt, [\xb, #URTX0] /* -> Transmitter Register */ > +.endm > + > +/* > + * Local variables: > + * mode: ASM > + * indent-tabs-mode: nil > + * End: > + */ > diff --git a/xen/arch/arm/include/asm/imx-uart.h > b/xen/arch/arm/include/asm/imx-uart.h > new file mode 100644 > index 0000000000..413a81dd44 > --- /dev/null > +++ b/xen/arch/arm/include/asm/imx-uart.h > @@ -0,0 +1,76 @@ > +/* SPDX-License-Identifier: GPL-2.0-or-later */ > +/* > + * xen/arch/arm/include/asm/imx-uart.h > + * > + * Common constant definition between early printk and the UART driver > + * > + * Copyright (C) 2024 EPAM Systems Inc. > + */ > + > +#ifndef __ASM_ARM_IMX_UART_H__ > +#define __ASM_ARM_IMX_UART_H__ > + > +/* 32-bit register definition */ > +#define URXD0 (0x00) /* Receiver Register */ There is no need to surround these values > +#define URTX0 (0x40) /* Transmitter Register */ > +#define UCR1 (0x80) /* Control Register 1 */ > +#define UCR2 (0x84) /* Control Register 2 */ > +#define UCR3 (0x88) /* Control Register 3 */ > +#define UCR4 (0x8c) /* Control Register 4 */ > +#define UFCR (0x90) /* FIFO Control Register */ > +#define USR1 (0x94) /* Status Register 1 */ > +#define USR2 (0x98) /* Status Register 2 */ > +#define IMX21_UTS (0xb4) /* Test Register */ > + > +#define URXD_ERR BIT(14, UL) /* Error detect */ > +#define URXD_RX_DATA GENMASK(7, 0) /* Received data mask */ > + > +#define UCR1_TRDYEN BIT(13, UL) /* Transmitter ready interrupt enable */ > +#define UCR1_RRDYEN BIT(9, UL) /* Receiver ready interrupt enable */ NIT: please align comments within a block Other than that: Reviewed-by: Michal Orzel <[email protected]> ~Michal
