[src/trunk]: src/sys/arch/arm/amlogic - since ttyinput (t_linesw->l_rint) sho...

[ryo <ryo%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/40ce99cface2
branches:  trunk
changeset: 456803:40ce99cface2
user:      ryo <ryo%NetBSD.org@localhost>
date:      Tue May 28 05:08:47 2019 +0000

description:
- since ttyinput (t_linesw->l_rint) should not be called from interrupt context,
  it has been modified to use softint like other serial drivers.
- add spinlock for interrupt.

ok jmcneill@. thanks

diffstat:

 sys/arch/arm/amlogic/meson_uart.c |  42 ++++++++++++++++++++++++++++++++++++--
 1 files changed, 39 insertions(+), 3 deletions(-)

diffs (111 lines):

diff -r 998628061788 -r 40ce99cface2 sys/arch/arm/amlogic/meson_uart.c
--- a/sys/arch/arm/amlogic/meson_uart.c Tue May 28 05:07:13 2019 +0000
+++ b/sys/arch/arm/amlogic/meson_uart.c Tue May 28 05:08:47 2019 +0000
@@ -1,4 +1,4 @@
-/* $NetBSD: meson_uart.c,v 1.2 2019/01/20 15:56:40 jmcneill Exp $ */
+/* $NetBSD: meson_uart.c,v 1.3 2019/05/28 05:08:47 ryo Exp $ */
 
 /*-
  * Copyright (c) 2013 The NetBSD Foundation, Inc.
@@ -34,7 +34,7 @@
 
 #include <sys/cdefs.h>
 
-__KERNEL_RCSID(1, "$NetBSD: meson_uart.c,v 1.2 2019/01/20 15:56:40 jmcneill Exp $");
+__KERNEL_RCSID(1, "$NetBSD: meson_uart.c,v 1.3 2019/05/28 05:08:47 ryo Exp $");
 
 #define cn_trap()                      \
        do {                            \
@@ -64,6 +64,7 @@
 static void    meson_uart_attach(device_t, device_t, void *);
 
 static int     meson_uart_intr(void *);
+static void    meson_uart_rxsoft(void *);
 
 static int     meson_uart_cngetc(dev_t);
 static void    meson_uart_cnputc(dev_t, int);
@@ -86,14 +87,20 @@
        device_t sc_dev;
        bus_space_tag_t sc_bst;
        bus_space_handle_t sc_bsh;
+       kmutex_t sc_intr_lock;
        void *sc_ih;
+       void *sc_sih;
 
        struct tty *sc_tty;
 
        int sc_ospeed;
+       unsigned int sc_rbuf_w;         /* write ptr of sc_rbuf[] */
+       unsigned int sc_rbuf_r;         /* read ptr of sc_rbuf[] */
        tcflag_t sc_cflag;
 
        u_char sc_buf[1024];
+#define MESON_RBUFSZ   128             /* must be 2^n */
+       u_char sc_rbuf[MESON_RBUFSZ];   /* good enough for sizeof RXFIFO */
 };
 
 static int meson_uart_console_phandle = -1;
@@ -179,6 +186,7 @@
                return;
        }
 
+       mutex_init(&sc->sc_intr_lock, MUTEX_DEFAULT, IPL_SERIAL);
        sc->sc_ih = fdtbus_intr_establish(phandle, 0, IPL_SERIAL,
            FDT_INTR_MPSAFE, meson_uart_intr, sc);
        if (sc->sc_ih == NULL) {
@@ -187,6 +195,12 @@
                return;
        }
 
+       sc->sc_sih = softint_establish(SOFTINT_SERIAL, meson_uart_rxsoft, sc);
+       if (sc->sc_sih == NULL) {
+               aprint_error(": failed to establish softint\n");
+               return;
+       }
+
        if (meson_uart_cmajor == -1) {
                /* allocate a major number */
                int bmajor = -1, cmajor = -1;
@@ -450,6 +464,7 @@
        struct tty *tp = sc->sc_tty;
        uint32_t status, c;
 
+       mutex_spin_enter(&sc->sc_intr_lock);
        for (;;) {
                int cn_trapped = 0;
                status = bus_space_read_4(sc->sc_bst, sc->sc_bsh,
@@ -468,12 +483,33 @@
                cn_check_magic(tp->t_dev, c & 0xff, meson_uart_cnm_state);
                if (cn_trapped)
                        continue;
-               tp->t_linesw->l_rint(c & 0xff, tp);
+
+               if ((sc->sc_rbuf_w - sc->sc_rbuf_r) >= (MESON_RBUFSZ - 1))
+                       continue;
+               sc->sc_rbuf[sc->sc_rbuf_w++ & (MESON_RBUFSZ - 1)] = c;
        }
+       mutex_spin_exit(&sc->sc_intr_lock);
+
+       if (sc->sc_rbuf_w != sc->sc_rbuf_r)
+               softint_schedule(sc->sc_sih);
 
        return 0;
 }
 
+static void
+meson_uart_rxsoft(void *priv)
+{
+       struct meson_uart_softc *sc = priv;
+       struct tty *tp = sc->sc_tty;
+       int c;
+
+       while (sc->sc_rbuf_w != sc->sc_rbuf_r) {
+               c = sc->sc_rbuf[sc->sc_rbuf_r++ & (MESON_RBUFSZ - 1)];
+               if (tp->t_linesw->l_rint(c & 0xff, tp) == -1)
+                       break;
+       }
+}
+
 static int
 meson_uart_console_match(int phandle)
 {