Re: [U-Boot] [PATCH v5] nios2: convert altera_jtag_uart to driver model

Hi Thomas,

On 18 September 2015 at 00:23, Thomas Chou thomas@wytron.com.tw wrote:

Convert altera_jtag_uart to driver model.

Signed-off-by: Thomas Chou thomas@wytron.com.tw

v2 add ioremap. make the change to dts compatible with linux.

v3 use fdt address translation patch from Stefan Roese. fix watchdog and loop as Marek suggested.

v4 add clear AC flag to probe(). remove polling loops and watchdog reset because they are done in the serial-uclass.c.

v5 fix coding style as Marek suggested to altera_uart.

arch/nios2/dts/3c120_devboard.dts | 5 ++ configs/nios2-generic_defconfig | 3 + drivers/serial/Kconfig | 13 ++++ drivers/serial/altera_jtag_uart.c | 145 ++++++++++++++++++++++---------------- include/configs/nios2-generic.h | 3 - 5 files changed, 106 insertions(+), 63 deletions(-)

This looks right to me but I have some comments below.

Reviewed-by: Simon Glass sjg@chromium.org

diff --git a/arch/nios2/dts/3c120_devboard.dts b/arch/nios2/dts/3c120_devboard.dts index 02524ab..7f76328 100644 --- a/arch/nios2/dts/3c120_devboard.dts +++ b/arch/nios2/dts/3c120_devboard.dts @@ -93,6 +93,7 @@ reg = <0x00004d50 0x00000008>; interrupt-parent = <&cpu>; interrupts = <1>;

•                           u-boot,dm-pre-reloc;
                    };
  
                    tse_mac: ethernet@0x4000 {
  

@@ -147,6 +148,10 @@ }; };

•   aliases {
  

•           console = &jtag_uart;
  

The normal way is to put this into the 'chosen' node, with the property name stdout-path.

•   };
  

•   chosen {
            bootargs = "debug console=ttyJ0,115200";
    };
  

diff --git a/configs/nios2-generic_defconfig b/configs/nios2-generic_defconfig index 9c1bec5..9dc6a72 100644 --- a/configs/nios2-generic_defconfig +++ b/configs/nios2-generic_defconfig @@ -1,4 +1,5 @@ CONFIG_NIOS2=y +CONFIG_DM_SERIAL=y CONFIG_TARGET_NIOS2_GENERIC=y CONFIG_DEFAULT_DEVICE_TREE="3c120_devboard" CONFIG_HUSH_PARSER=y @@ -14,3 +15,5 @@ CONFIG_CMD_PING=y CONFIG_OF_CONTROL=y CONFIG_NET_RANDOM_ETHADDR=y CONFIG_DM=y +CONFIG_ALTERA_JTAG_UART=y +CONFIG_ALTERA_JTAG_UART_BYPASS=y diff --git a/drivers/serial/Kconfig b/drivers/serial/Kconfig index ccb80d2..5a8cb3a 100644 --- a/drivers/serial/Kconfig +++ b/drivers/serial/Kconfig @@ -109,6 +109,19 @@ config DEBUG_UART_SHIFT value. Use this value to specify the shift to use, where 0=byte registers, 2=32-bit word registers, etc.

+config ALTERA_JTAG_UART

•   bool "Altera JTAG UART support"
  

•   depends on NIOS2 && DM_SERIAL
  

•   help
  

•     Select this to enable an JTAG UART for Altera devices.
  

a JTAG UART

Is there anything else to say about it? Perhaps how it works? A link to instructions on how to set it up?

+config ALTERA_JTAG_UART_BYPASS

•   bool "Bypass output when no connection"
  

•   depends on ALTERA_JTAG_UART
  

•   help
  

•     Bypass console output and keep going even if there is no
  

•     JTAG terminal connection with the host.
  

config ROCKCHIP_SERIAL bool "Rockchip on-chip UART support" depends on ARCH_UNIPHIER && DM_SERIAL diff --git a/drivers/serial/altera_jtag_uart.c b/drivers/serial/altera_jtag_uart.c index 9a81402..2c025bc 100644 --- a/drivers/serial/altera_jtag_uart.c +++ b/drivers/serial/altera_jtag_uart.c @@ -6,98 +6,123 @@ */

#include <common.h> -#include <watchdog.h> +#include <dm.h> +#include <errno.h> #include <asm/io.h> #include <linux/compiler.h> #include <serial.h>

-typedef volatile struct {

•   unsigned        data;                   /* Data register */
  

•   unsigned        control;                /* Control register */
  

-} nios_jtag_t; +struct altera_jtaguart_regs {

•   u32     data;                   /* Data register */
  

•   u32     control;                /* Control register */
  

+};

+struct altera_jtaguart_platdata {

•   struct altera_jtaguart_regs *reg;
  

+};

/* data register */ #define NIOS_JTAG_RVALID (1<<15) /* Read valid */ -#define NIOS_JTAG_DATA(d) ((d)&0x0ff) /* Read data */ -#define NIOS_JTAG_RAVAIL(d) ((d)>>16) /* Read space avail */

/* control register */ -#define NIOS_JTAG_RE (1 << 0) /* read intr enable */ -#define NIOS_JTAG_WE (1 << 1) /* write intr enable */ -#define NIOS_JTAG_RI (1 << 8) /* read intr pending */ -#define NIOS_JTAG_WI (1 << 9) /* write intr pending*/ #define NIOS_JTAG_AC (1 << 10) /* activity indicator */ #define NIOS_JTAG_RRDY (1 << 12) /* read available */ #define NIOS_JTAG_WSPACE(d) ((d)>>16) /* Write space avail */ +/* Write fifo size. FIXME: this should be extracted with sopc2dts */ +#define NIOS_JTAG_WRITE_DEPTH 64

DECLARE_GLOBAL_DATA_PTR;

-/*------------------------------------------------------------------

• • JTAG acts as the serial port
• *-----------------------------------------------------------------*/

-static nios_jtag_t *jtag = (nios_jtag_t *)CONFIG_SYS_NIOS_CONSOLE;

-static void altera_jtag_serial_setbrg(void) -{ -}

-static int altera_jtag_serial_init(void) +static int altera_jtaguart_setbrg(struct udevice *dev, int baudrate) { return 0; }

-static void altera_jtag_serial_putc(char c) +static int altera_jtaguart_putc(struct udevice *dev, const char c)

While you are here, how abouve 'ch' instead of 'c' as it is easier to spot.

{

•   while (1) {
  

•           unsigned st = readl(&jtag->control);
  

•           if (NIOS_JTAG_WSPACE(st))
  

•                   break;
  

•   struct altera_jtaguart_platdata *plat = dev->platdata;
  

•   struct altera_jtaguart_regs *const regs = plat->reg;
  

•   u32 st = readl(&regs->control);
  

#ifdef CONFIG_ALTERA_JTAG_UART_BYPASS

It seems odd that you return this error when writing a character. Don't you know whether the connection is valid in the probe() method? Or are you trying to avoid an error at that stage?

•           if (!(st & NIOS_JTAG_AC)) /* no connection */
  

•                   return;
  

•   if (!(st & NIOS_JTAG_AC)) /* no connection */
  

•           return -ENETUNREACH;
  

#endif

•           WATCHDOG_RESET();
  

•   }
  

•   writel ((unsigned char)c, &jtag->data);
  

•   if (NIOS_JTAG_WSPACE(st) == 0)
  

•           return -EAGAIN;
  

•   writel(c, &regs->data);
  

•   return 0;
  

}

-static int altera_jtag_serial_tstc(void) +static int altera_jtaguart_pending(struct udevice *dev, bool input) {

•   return ( readl (&jtag->control) & NIOS_JTAG_RRDY);
  

•   struct altera_jtaguart_platdata *plat = dev->platdata;
  

•   struct altera_jtaguart_regs *const regs = plat->reg;
  

•   u32 st = readl(&regs->control);
  

•   if (input)
  

•           return st & NIOS_JTAG_RRDY;
  

I think this should be:

return st & NIOS_JTAG_RRDY ? 1 : 0;

•   else
  

•           return !(NIOS_JTAG_WSPACE(st) == NIOS_JTAG_WRITE_DEPTH);
  

}

-static int altera_jtag_serial_getc(void) +static int altera_jtaguart_getc(struct udevice *dev) {

•   int c;
  

•   unsigned val;
  

•   while (1) {
  

•           WATCHDOG_RESET ();
  

•           val = readl (&jtag->data);
  

•           if (val & NIOS_JTAG_RVALID)
  

•                   break;
  

•   }
  

•   c = val & 0x0ff;
  

•   return (c);
  

-}

•   struct altera_jtaguart_platdata *plat = dev->platdata;
  

•   struct altera_jtaguart_regs *const regs = plat->reg;
  

•   u32 val;
  
  

-static struct serial_device altera_jtag_serial_drv = {

•   .name   = "altera_jtag_uart",
  

•   .start  = altera_jtag_serial_init,
  

•   .stop   = NULL,
  

•   .setbrg = altera_jtag_serial_setbrg,
  

•   .putc   = altera_jtag_serial_putc,
  

•   .puts   = default_serial_puts,
  

•   .getc   = altera_jtag_serial_getc,
  

•   .tstc   = altera_jtag_serial_tstc,
  

-};

•   val = readl(&regs->data);
  

•   if (!(val & NIOS_JTAG_RVALID))
  

•           return -EAGAIN;
  
  

-void altera_jtag_serial_initialize(void)

•   return val & 0xff;
  

+}

+static int altera_jtaguart_probe(struct udevice *dev) {

•   serial_register(&altera_jtag_serial_drv);
  

•   struct altera_jtaguart_platdata *plat = dev->platdata;
  

•   struct altera_jtaguart_regs *const regs = plat->reg;
  

+#ifdef CONFIG_ALTERA_JTAG_UART_BYPASS

•   writel(NIOS_JTAG_AC, &regs->control); /* clear AC flag */
  

+#endif

•   return 0;
  

}

-__weak struct serial_device *default_serial_console(void) +static int altera_jtaguart_ofdata_to_platdata(struct udevice *dev) {

•   return &altera_jtag_serial_drv;
  

•   struct altera_jtaguart_platdata *plat = dev_get_platdata(dev);
  

•   plat->reg = ioremap(dev_get_addr(dev),
  

•           sizeof(struct altera_jtaguart_regs));
  

What is the ioremap() for? Is this because we don't support ranges properly yet? If so, perhaps we can assume that will be fixed before this is applied?

•   return 0;
  

}

+static const struct dm_serial_ops altera_jtaguart_ops = {

•   .putc = altera_jtaguart_putc,
  

•   .pending = altera_jtaguart_pending,
  

•   .getc = altera_jtaguart_getc,
  

•   .setbrg = altera_jtaguart_setbrg,
  

+};

+static const struct udevice_id altera_jtaguart_ids[] = {

•   { .compatible = "altr,juart-1.0", },
  

•   { }
  

+};

+U_BOOT_DRIVER(altera_jtaguart) = {

•   .name   = "altera_jtaguart",
  

•   .id     = UCLASS_SERIAL,
  

•   .of_match = altera_jtaguart_ids,
  

•   .ofdata_to_platdata = altera_jtaguart_ofdata_to_platdata,
  

•   .platdata_auto_alloc_size = sizeof(struct altera_jtaguart_platdata),
  

•   .probe = altera_jtaguart_probe,
  

•   .ops    = &altera_jtaguart_ops,
  

•   .flags = DM_FLAG_PRE_RELOC,
  

+}; diff --git a/include/configs/nios2-generic.h b/include/configs/nios2-generic.h index 66ad2f0..bd6d45c 100644 --- a/include/configs/nios2-generic.h +++ b/include/configs/nios2-generic.h @@ -23,14 +23,11 @@ /*

• SERIAL

*/ -#define CONFIG_ALTERA_JTAG_UART #if defined(CONFIG_ALTERA_JTAG_UART) -# define CONFIG_SYS_NIOS_CONSOLE CONFIG_SYS_JTAG_UART_BASE #else # define CONFIG_SYS_NIOS_CONSOLE CONFIG_SYS_UART_BASE #endif

-#define CONFIG_ALTERA_JTAG_UART_BYPASS #define CONFIG_SYS_NIOS_FIXEDBAUD #define CONFIG_BAUDRATE CONFIG_SYS_UART_BAUD

#define CONFIG_SYS_BAUDRATE_TABLE {CONFIG_BAUDRATE}

2.1.4

Regards, Simon