[PATCH 1/1] lib: utils/serial: Add support for Gaisler APBUART
Bin Meng
bmeng.cn at gmail.com
Fri Apr 30 10:16:28 BST 2021
On Fri, Apr 30, 2021 at 2:37 PM Daniel Cederman <cederman at gaisler.com> wrote:
>
> This patch adds support for the UART used by the NOEL-V processor.
>
> Cobham Gaisler's NOEL-V RISC-V processor IP is available under GPL
> and commercial license and is described in more detail at
> https://www.gaisler.com/noelv.
>
> Signed-off-by: Daniel Cederman <cederman at gaisler.com>
> ---
> include/sbi_utils/fdt/fdt_helper.h | 3 +
> include/sbi_utils/serial/gaisler-uart.h | 17 +++++
> lib/utils/fdt/fdt_helper.c | 40 ++++++++++++
> lib/utils/serial/fdt_serial.c | 2 +
> lib/utils/serial/fdt_serial_gaisler.c | 35 ++++++++++
> lib/utils/serial/gaisler-uart.c | 86 +++++++++++++++++++++++++
> lib/utils/serial/objects.mk | 2 +
> 7 files changed, 185 insertions(+)
> create mode 100644 include/sbi_utils/serial/gaisler-uart.h
> create mode 100644 lib/utils/serial/fdt_serial_gaisler.c
> create mode 100644 lib/utils/serial/gaisler-uart.c
>
> diff --git a/include/sbi_utils/fdt/fdt_helper.h b/include/sbi_utils/fdt/fdt_helper.h
> index f5222de..c89f2e6 100644
> --- a/include/sbi_utils/fdt/fdt_helper.h
> +++ b/include/sbi_utils/fdt/fdt_helper.h
> @@ -39,6 +39,9 @@ int fdt_parse_hart_id(void *fdt, int cpu_offset, u32 *hartid);
>
> int fdt_parse_max_hart_id(void *fdt, u32 *max_hartid);
>
> +int fdt_parse_gaisler_uart_node(void *fdt, int nodeoffset,
> + struct platform_uart_data *uart);
> +
> int fdt_parse_shakti_uart_node(void *fdt, int nodeoffset,
> struct platform_uart_data *uart);
>
> diff --git a/include/sbi_utils/serial/gaisler-uart.h b/include/sbi_utils/serial/gaisler-uart.h
> new file mode 100644
> index 0000000..11d1f20
> --- /dev/null
> +++ b/include/sbi_utils/serial/gaisler-uart.h
> @@ -0,0 +1,17 @@
> +/*
> + * SPDX-License-Identifier: BSD-2-Clause
> + *
> + * Copyright (c) 2021 Cobham Gaisler AB.
> + *
> + * Authors:
> + * Daniel Cederman <cederman at gaisler.com>
> + */
> +
> +#ifndef __SERIAL_GAISLER_APBUART_H__
> +#define __SERIAL_GAISLER_APBUART_H__
> +
> +#include <sbi/sbi_types.h>
> +
> +int gaisler_uart_init(unsigned long base, u32 in_freq, u32 baudrate);
> +
> +#endif
> diff --git a/lib/utils/fdt/fdt_helper.c b/lib/utils/fdt/fdt_helper.c
> index 909de01..9143e44 100644
> --- a/lib/utils/fdt/fdt_helper.c
> +++ b/lib/utils/fdt/fdt_helper.c
> @@ -26,6 +26,8 @@
> #define DEFAULT_SIFIVE_UART_REG_SHIFT 0
> #define DEFAULT_SIFIVE_UART_REG_IO_WIDTH 4
>
> +#define DEFAULT_GAISLER_UART_REG_IO_WIDTH 4
> +
> #define DEFAULT_SHAKTI_UART_FREQ 50000000
> #define DEFAULT_SHAKTI_UART_BAUD 115200
>
> @@ -213,6 +215,44 @@ int fdt_parse_max_hart_id(void *fdt, u32 *max_hartid)
> return 0;
> }
>
> +int fdt_parse_gaisler_uart_node(void *fdt, int nodeoffset,
> + struct platform_uart_data *uart)
> +{
> + int len, rc;
> + const fdt32_t *val;
> + unsigned long reg_addr, reg_size;
> +
> + if (nodeoffset < 0 || !uart || !fdt)
> + return SBI_ENODEV;
> +
> + rc = fdt_get_node_addr_size(fdt, nodeoffset, ®_addr, ®_size);
> + if (rc < 0 || !reg_addr || !reg_size)
> + return SBI_ENODEV;
> + uart->addr = reg_addr;
> +
> + /**
> + * UART address is mandatory. clock-frequency and current-speed
> + * may not be present. Don't return error.
> + */
> + val = (fdt32_t *)fdt_getprop(fdt, nodeoffset, "clock-frequency", &len);
> + if (len > 0 && val)
> + uart->freq = fdt32_to_cpu(*val);
> + else
> + uart->freq = DEFAULT_UART_FREQ;
> +
> + val = (fdt32_t *)fdt_getprop(fdt, nodeoffset, "current-speed", &len);
> + if (len > 0 && val)
> + uart->baud = fdt32_to_cpu(*val);
> + else
> + uart->baud = DEFAULT_UART_BAUD;
> +
> + /* For Gaisler APBUART, the reg-shift and reg-io-width are fixed .*/
> + uart->reg_shift = DEFAULT_UART_REG_SHIFT;
> + uart->reg_io_width = DEFAULT_GAISLER_UART_REG_IO_WIDTH;
> +
> + return 0;
> +}
> +
> int fdt_parse_shakti_uart_node(void *fdt, int nodeoffset,
> struct platform_uart_data *uart)
> {
> diff --git a/lib/utils/serial/fdt_serial.c b/lib/utils/serial/fdt_serial.c
> index 43c55e8..bad3387 100644
> --- a/lib/utils/serial/fdt_serial.c
> +++ b/lib/utils/serial/fdt_serial.c
> @@ -16,12 +16,14 @@ extern struct fdt_serial fdt_serial_uart8250;
> extern struct fdt_serial fdt_serial_sifive;
> extern struct fdt_serial fdt_serial_htif;
> extern struct fdt_serial fdt_serial_shakti;
> +extern struct fdt_serial fdt_serial_gaisler;
>
> static struct fdt_serial *serial_drivers[] = {
> &fdt_serial_uart8250,
> &fdt_serial_sifive,
> &fdt_serial_htif,
> &fdt_serial_shakti,
> + &fdt_serial_gaisler
> };
>
> static struct fdt_serial dummy = {
> diff --git a/lib/utils/serial/fdt_serial_gaisler.c b/lib/utils/serial/fdt_serial_gaisler.c
> new file mode 100644
> index 0000000..9a9f9a8
> --- /dev/null
> +++ b/lib/utils/serial/fdt_serial_gaisler.c
> @@ -0,0 +1,35 @@
> +/*
> + * SPDX-License-Identifier: BSD-2-Clause
> + *
> + * Copyright (c) 2021 Cobham Gaisler AB.
> + *
> + * Authors:
> + * Daniel Cederman <cederman at gaisler.com>
> + */
> +
> +#include <sbi_utils/fdt/fdt_helper.h>
> +#include <sbi_utils/serial/fdt_serial.h>
> +#include <sbi_utils/serial/gaisler-uart.h>
> +
> +static int serial_gaisler_init(void *fdt, int nodeoff,
> + const struct fdt_match *match)
> +{
> + int rc;
> + struct platform_uart_data uart;
> +
> + rc = fdt_parse_gaisler_uart_node(fdt, nodeoff, &uart);
> + if (rc)
> + return rc;
> +
> + return gaisler_uart_init(uart.addr, uart.freq, uart.baud);
> +}
> +
> +static const struct fdt_match serial_gaisler_match[] = {
> + { .compatible = "gaisler,apbuart" },
Is this an approved compatible string? I did not find such in the
upstream Linux kernel.
> + {},
> +};
> +
> +struct fdt_serial fdt_serial_gaisler = {
> + .match_table = serial_gaisler_match,
> + .init = serial_gaisler_init
> +};
> diff --git a/lib/utils/serial/gaisler-uart.c b/lib/utils/serial/gaisler-uart.c
> new file mode 100644
> index 0000000..49298e9
> --- /dev/null
[snip]
Regards,
Bin
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