[PATCH 1/1] lib: utils/serial: Add support for Gaisler APBUART
Bin Meng
bmeng.cn at gmail.com
Tue May 4 10:24:40 BST 2021
On Tue, May 4, 2021 at 11:46 AM Anup Patel <Anup.Patel at wdc.com> wrote:
>
>
>
> > -----Original Message-----
> > From: opensbi <opensbi-bounces at lists.infradead.org> On Behalf Of Daniel
> > Cederman
> > Sent: 30 April 2021 12:06
> > To: opensbi at lists.infradead.org
> > Cc: daniel at gaisler.com
> > Subject: [PATCH 1/1] lib: utils/serial: Add support for Gaisler APBUART
> >
> > 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>
>
> Looks good to me.
>
> Reviewed-by: Anup Patel <anup.patel at wdc.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" },
>
> We do have compatible strings in OpenSBI which are not standardized by
> Linux DT bindings so this compatible string is okay for now.
>
> It is very important that whenever Linux DT bindings are accepted, we
> add the accepted compatible string here as well.
Good to know :)
Reviewed-by: Bin Meng <bmeng.cn at gmail.com>
Regards,
Bin
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