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[PATCH V5 2/2] xen/arm: Add i.MX lpuart early printk support

Peng Fan (OSS) posted 2 patches 3 years, 10 months ago
There is a newer version of this series
[PATCH V5 2/2] xen/arm: Add i.MX lpuart early printk support
Posted by Peng Fan (OSS) 3 years, 10 months ago 
From: Peng Fan <peng.fan@nxp.com>

Signed-off-by: Peng Fan <peng.fan@nxp.com>
---
 xen/arch/arm/Kconfig.debug              | 14 ++++++++
 xen/arch/arm/arm64/debug-imx-lpuart.inc | 48 +++++++++++++++++++++++++
 2 files changed, 62 insertions(+)
 create mode 100644 xen/arch/arm/arm64/debug-imx-lpuart.inc

diff --git a/xen/arch/arm/Kconfig.debug b/xen/arch/arm/Kconfig.debug
index 35ccd13273..842d768280 100644
--- a/xen/arch/arm/Kconfig.debug
+++ b/xen/arch/arm/Kconfig.debug
@@ -58,6 +58,16 @@ choice
 			This option is preferred over the platform specific
 			options; the platform specific options are deprecated
 			and will soon be removed.
+	config EARLY_UART_CHOICE_IMX_LPUART
+		select EARLY_UART_IMX_LPUART
+		depends on ARM_64
+		bool "Early printk via i.MX LPUART"
+		help
+			Say Y here if you wish the early printk to direct their
+			output to a i.MX LPUART. You can use this option to
+			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_MESON
 		select EARLY_UART_MESON
 		depends on ARM_64
@@ -186,6 +196,9 @@ config EARLY_UART_CADENCE
 config EARLY_UART_EXYNOS4210
 	select EARLY_PRINTK
 	bool
+config EARLY_UART_IMX_LPUART
+	select EARLY_PRINTK
+	bool
 config EARLY_UART_MESON
 	select EARLY_PRINTK
 	bool
@@ -283,6 +296,7 @@ config EARLY_PRINTK_INC
 	default "debug-8250.inc" if EARLY_UART_8250
 	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-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-lpuart.inc b/xen/arch/arm/arm64/debug-imx-lpuart.inc
new file mode 100644
index 0000000000..b169332932
--- /dev/null
+++ b/xen/arch/arm/arm64/debug-imx-lpuart.inc
@@ -0,0 +1,48 @@
+/*
+ * xen/arch/arm/arm64/debug-imx-lpuart.inc
+ *
+ * i.MX8QM specific debug code
+ *
+ * Peng Fan <peng.fan@nxp.com>
+ * Copyright 2022 NXP
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <asm/imx-lpuart.h>
+
+/*
+ * Wait LPUART 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, #UARTSTAT]   /* <- Flag register */
+        tst   w\c, #UARTSTAT_TDRE     /* Check FIFO EMPTY bit */
+        beq   1b                      /* Wait for the UART to be ready */
+.endm
+
+/*
+ * LPUART 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, #UARTDATA]  /* -> Data Register */
+.endm
+
+/*
+ * Local variables:
+ * mode: ASM
+ * indent-tabs-mode: nil
+ * End:
+ */
-- 
2.35.1
Re: [PATCH V5 2/2] xen/arm: Add i.MX lpuart early printk support
Posted by Bertrand Marquis 3 years, 10 months ago 
Hi Peng,

> On 14 Apr 2022, at 08:44, Peng Fan (OSS) <peng.fan@oss.nxp.com> wrote:
> 
> From: Peng Fan <peng.fan@nxp.com>
> 
> Signed-off-by: Peng Fan <peng.fan@nxp.com>
Acked-by: Bertrand Marquis <bertrand.marquis@arm.com>

Cheers
Bertrand

> ---
> xen/arch/arm/Kconfig.debug              | 14 ++++++++
> xen/arch/arm/arm64/debug-imx-lpuart.inc | 48 +++++++++++++++++++++++++
> 2 files changed, 62 insertions(+)
> create mode 100644 xen/arch/arm/arm64/debug-imx-lpuart.inc
> 
> diff --git a/xen/arch/arm/Kconfig.debug b/xen/arch/arm/Kconfig.debug
> index 35ccd13273..842d768280 100644
> --- a/xen/arch/arm/Kconfig.debug
> +++ b/xen/arch/arm/Kconfig.debug
> @@ -58,6 +58,16 @@ choice
> 			This option is preferred over the platform specific
> 			options; the platform specific options are deprecated
> 			and will soon be removed.
> +	config EARLY_UART_CHOICE_IMX_LPUART
> +		select EARLY_UART_IMX_LPUART
> +		depends on ARM_64
> +		bool "Early printk via i.MX LPUART"
> +		help
> +			Say Y here if you wish the early printk to direct their
> +			output to a i.MX LPUART. You can use this option to
> +			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_MESON
> 		select EARLY_UART_MESON
> 		depends on ARM_64
> @@ -186,6 +196,9 @@ config EARLY_UART_CADENCE
> config EARLY_UART_EXYNOS4210
> 	select EARLY_PRINTK
> 	bool
> +config EARLY_UART_IMX_LPUART
> +	select EARLY_PRINTK
> +	bool
> config EARLY_UART_MESON
> 	select EARLY_PRINTK
> 	bool
> @@ -283,6 +296,7 @@ config EARLY_PRINTK_INC
> 	default "debug-8250.inc" if EARLY_UART_8250
> 	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-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-lpuart.inc b/xen/arch/arm/arm64/debug-imx-lpuart.inc
> new file mode 100644
> index 0000000000..b169332932
> --- /dev/null
> +++ b/xen/arch/arm/arm64/debug-imx-lpuart.inc
> @@ -0,0 +1,48 @@
> +/*
> + * xen/arch/arm/arm64/debug-imx-lpuart.inc
> + *
> + * i.MX8QM specific debug code
> + *
> + * Peng Fan <peng.fan@nxp.com>
> + * Copyright 2022 NXP
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License as published by
> + * the Free Software Foundation; either version 2 of the License, or
> + * (at your option) any later version.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> + * GNU General Public License for more details.
> + */
> +
> +#include <asm/imx-lpuart.h>
> +
> +/*
> + * Wait LPUART 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, #UARTSTAT]   /* <- Flag register */
> +        tst   w\c, #UARTSTAT_TDRE     /* Check FIFO EMPTY bit */
> +        beq   1b                      /* Wait for the UART to be ready */
> +.endm
> +
> +/*
> + * LPUART 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, #UARTDATA]  /* -> Data Register */
> +.endm
> +
> +/*
> + * Local variables:
> + * mode: ASM
> + * indent-tabs-mode: nil
> + * End:
> + */
> -- 
> 2.35.1
>
Re: [PATCH V5 2/2] xen/arm: Add i.MX lpuart early printk support
Posted by Michal Orzel 3 years, 10 months ago 
On 14.04.2022 09:44, Peng Fan (OSS) wrote:
> From: Peng Fan <peng.fan@nxp.com>
> 
> Signed-off-by: Peng Fan <peng.fan@nxp.com>

Reviewed-by: Michal Orzel <michal.orzel@arm.com>

Cheers,
Michal

Patchew 2.1-devel-b67e4c2

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