Merge tag 'renesas-sh-sci-for-v3.11' of git://git.kernel.org/pub/scm/linux/kernel/git/horms/renesas into next/late

Renesas sh-sci updates for v3.11

HSCIF support by Ulrich Hecht.

* tag 'renesas-sh-sci-for-v3.11' of git://git.kernel.org/pub/scm/linux/kernel/git/horms/renesas:
  serial: sh-sci: Initialise variables before access in sci_set_termios()
  ARM: shmobile: r8a7790: don't use external clock for SCIFs
  ARM: shmobile: r8a7790: HSCIF support
  serial: sh-sci: HSCIF support

Signed-off-by: Arnd Bergmann <arnd@arndb.de>

4 files changed, 121 insertions, 14 deletions

diff --git a/arch/arm/mach-shmobile/setup-r8a7790.c b/arch/arm/mach-shmobile/setup-r8a7790.c
index 196bd7325df0..28f94752b8ff 100644
--- a/arch/arm/mach-shmobile/setup-r8a7790.c
+++ b/arch/arm/mach-shmobile/setup-r8a7790.c
@@ -98,10 +98,18 @@ void __init r8a7790_pinmux_init(void)
 [index] = {                                             \
         SCIF_COMMON(PORT_SCIF, baseaddr, irq),          \
         .scbrr_algo_id  = SCBRR_ALGO_2,                 \
-        .scscr = SCSCR_RE | SCSCR_TE | SCSCR_CKE1,      \
+        .scscr = SCSCR_RE | SCSCR_TE,   \
 }
 
-enum { SCIFA0, SCIFA1, SCIFB0, SCIFB1, SCIFB2, SCIFA2, SCIF0, SCIF1 };
+#define HSCIF_DATA(index, baseaddr, irq)                \
+[index] = {                                             \
+        SCIF_COMMON(PORT_HSCIF, baseaddr, irq),         \
+        .scbrr_algo_id  = SCBRR_ALGO_6,                 \
+        .scscr = SCSCR_RE | SCSCR_TE,   \
+}
+
+enum { SCIFA0, SCIFA1, SCIFB0, SCIFB1, SCIFB2, SCIFA2, SCIF0, SCIF1,
+       HSCIF0, HSCIF1 };
 
 static struct plat_sci_port scif[] __initdata = {
         SCIFA_DATA(SCIFA0, 0xe6c40000, gic_spi(144)), /* SCIFA0 */
@@ -112,6 +120,8 @@ static struct plat_sci_port scif[] __initdata = {
         SCIFA_DATA(SCIFA2, 0xe6c60000, gic_spi(151)), /* SCIFA2 */
         SCIF_DATA(SCIF0, 0xe6e60000, gic_spi(152)), /* SCIF0 */
         SCIF_DATA(SCIF1, 0xe6e68000, gic_spi(153)), /* SCIF1 */
+        HSCIF_DATA(HSCIF0, 0xe62c0000, gic_spi(154)), /* HSCIF0 */
+        HSCIF_DATA(HSCIF1, 0xe62c8000, gic_spi(155)), /* HSCIF1 */
 };
 
 static inline void r8a7790_register_scif(int idx)
@@ -149,6 +159,8 @@ void __init r8a7790_add_standard_devices(void)
         r8a7790_register_scif(SCIFA2);
         r8a7790_register_scif(SCIF0);
         r8a7790_register_scif(SCIF1);
+        r8a7790_register_scif(HSCIF0);
+        r8a7790_register_scif(HSCIF1);
         r8a7790_register_irqc(0);
 }
 
diff --git a/drivers/tty/serial/sh-sci.c b/drivers/tty/serial/sh-sci.c
index 156418619949..7477e0ea5cdb 100644
--- a/drivers/tty/serial/sh-sci.c
+++ b/drivers/tty/serial/sh-sci.c
@@ -146,6 +146,7 @@ static struct plat_sci_reg sci_regmap[SCIx_NR_REGTYPES][SCIx_NR_REGS] = {
                 [SCRFDR]        = sci_reg_invalid,
                 [SCSPTR]        = sci_reg_invalid,
                 [SCLSR]         = sci_reg_invalid,
+                [HSSRR]         = sci_reg_invalid,
         },
 
         /*
@@ -165,6 +166,7 @@ static struct plat_sci_reg sci_regmap[SCIx_NR_REGTYPES][SCIx_NR_REGS] = {
                 [SCRFDR]        = sci_reg_invalid,
                 [SCSPTR]        = sci_reg_invalid,
                 [SCLSR]         = sci_reg_invalid,
+                [HSSRR]         = sci_reg_invalid,
         },
 
         /*
@@ -183,6 +185,7 @@ static struct plat_sci_reg sci_regmap[SCIx_NR_REGTYPES][SCIx_NR_REGS] = {
                 [SCRFDR]        = sci_reg_invalid,
                 [SCSPTR]        = sci_reg_invalid,
                 [SCLSR]         = sci_reg_invalid,
+                [HSSRR]         = sci_reg_invalid,
         },
 
         /*
@@ -201,6 +204,7 @@ static struct plat_sci_reg sci_regmap[SCIx_NR_REGTYPES][SCIx_NR_REGS] = {
                 [SCRFDR]        = { 0x3c, 16 },
                 [SCSPTR]        = sci_reg_invalid,
                 [SCLSR]         = sci_reg_invalid,
+                [HSSRR]         = sci_reg_invalid,
         },
 
         /*
@@ -220,6 +224,7 @@ static struct plat_sci_reg sci_regmap[SCIx_NR_REGTYPES][SCIx_NR_REGS] = {
                 [SCRFDR]        = sci_reg_invalid,
                 [SCSPTR]        = { 0x20, 16 },
                 [SCLSR]         = { 0x24, 16 },
+                [HSSRR]         = sci_reg_invalid,
         },
 
         /*
@@ -238,6 +243,7 @@ static struct plat_sci_reg sci_regmap[SCIx_NR_REGTYPES][SCIx_NR_REGS] = {
                 [SCRFDR]        = sci_reg_invalid,
                 [SCSPTR]        = sci_reg_invalid,
                 [SCLSR]         = sci_reg_invalid,
+                [HSSRR]         = sci_reg_invalid,
         },
 
         /*
@@ -256,6 +262,26 @@ static struct plat_sci_reg sci_regmap[SCIx_NR_REGTYPES][SCIx_NR_REGS] = {
                 [SCRFDR]        = sci_reg_invalid,
                 [SCSPTR]        = { 0x20, 16 },
                 [SCLSR]         = { 0x24, 16 },
+                [HSSRR]         = sci_reg_invalid,
+        },
+
+        /*
+         * Common HSCIF definitions.
+         */
+        [SCIx_HSCIF_REGTYPE] = {
+                [SCSMR]         = { 0x00, 16 },
+                [SCBRR]         = { 0x04,  8 },
+                [SCSCR]         = { 0x08, 16 },
+                [SCxTDR]        = { 0x0c,  8 },
+                [SCxSR]         = { 0x10, 16 },
+                [SCxRDR]        = { 0x14,  8 },
+                [SCFCR]         = { 0x18, 16 },
+                [SCFDR]         = { 0x1c, 16 },
+                [SCTFDR]        = sci_reg_invalid,
+                [SCRFDR]        = sci_reg_invalid,
+                [SCSPTR]        = { 0x20, 16 },
+                [SCLSR]         = { 0x24, 16 },
+                [HSSRR]         = { 0x40, 16 },
         },
 
         /*
@@ -275,6 +301,7 @@ static struct plat_sci_reg sci_regmap[SCIx_NR_REGTYPES][SCIx_NR_REGS] = {
                 [SCRFDR]        = sci_reg_invalid,
                 [SCSPTR]        = sci_reg_invalid,
                 [SCLSR]         = { 0x24, 16 },
+                [HSSRR]         = sci_reg_invalid,
         },
 
         /*
@@ -294,6 +321,7 @@ static struct plat_sci_reg sci_regmap[SCIx_NR_REGTYPES][SCIx_NR_REGS] = {
                 [SCRFDR]        = { 0x20, 16 },
                 [SCSPTR]        = { 0x24, 16 },
                 [SCLSR]         = { 0x28, 16 },
+                [HSSRR]         = sci_reg_invalid,
         },
 
         /*
@@ -313,6 +341,7 @@ static struct plat_sci_reg sci_regmap[SCIx_NR_REGTYPES][SCIx_NR_REGS] = {
                 [SCRFDR]        = sci_reg_invalid,
                 [SCSPTR]        = sci_reg_invalid,
                 [SCLSR]         = sci_reg_invalid,
+                [HSSRR]         = sci_reg_invalid,
         },
 };
 
@@ -374,6 +403,9 @@ static int sci_probe_regmap(struct plat_sci_port *cfg)
                  */
                 cfg->regtype = SCIx_SH4_SCIF_REGTYPE;
                 break;
+        case PORT_HSCIF:
+                cfg->regtype = SCIx_HSCIF_REGTYPE;
+                break;
         default:
                 printk(KERN_ERR "Can't probe register map for given port\n");
                 return -EINVAL;
@@ -1798,6 +1830,42 @@ static unsigned int sci_scbrr_calc(unsigned int algo_id, unsigned int bps,
         return ((freq + 16 * bps) / (32 * bps) - 1);
 }
 
+/* calculate sample rate, BRR, and clock select for HSCIF */
+static void sci_baud_calc_hscif(unsigned int bps, unsigned long freq,
+                                int *brr, unsigned int *srr,
+                                unsigned int *cks)
+{
+        int sr, c, br, err;
+        int min_err = 1000; /* 100% */
+
+        /* Find the combination of sample rate and clock select with the
+           smallest deviation from the desired baud rate. */
+        for (sr = 8; sr <= 32; sr++) {
+                for (c = 0; c <= 3; c++) {
+                        /* integerized formulas from HSCIF documentation */
+                        br = freq / (sr * (1 << (2 * c + 1)) * bps) - 1;
+                        if (br < 0 || br > 255)
+                                continue;
+                        err = freq / ((br + 1) * bps * sr *
+                              (1 << (2 * c + 1)) / 1000) - 1000;
+                        if (min_err > err) {
+                                min_err = err;
+                                *brr = br;
+                                *srr = sr - 1;
+                                *cks = c;
+                        }
+                }
+        }
+
+        if (min_err == 1000) {
+                WARN_ON(1);
+                /* use defaults */
+                *brr = 255;
+                *srr = 15;
+                *cks = 0;
+        }
+}
+
 static void sci_reset(struct uart_port *port)
 {
         struct plat_sci_reg *reg;
@@ -1819,8 +1887,9 @@ static void sci_set_termios(struct uart_port *port, struct ktermios *termios,
 {
         struct sci_port *s = to_sci_port(port);
         struct plat_sci_reg *reg;
-        unsigned int baud, smr_val, max_baud, cks;
+        unsigned int baud, smr_val, max_baud, cks = 0;
         int t = -1;
+        unsigned int srr = 15;
 
         /*
          * earlyprintk comes here early on with port->uartclk set to zero.
@@ -1833,8 +1902,17 @@ static void sci_set_termios(struct uart_port *port, struct ktermios *termios,
         max_baud = port->uartclk ? port->uartclk / 16 : 115200;
 
         baud = uart_get_baud_rate(port, termios, old, 0, max_baud);
-        if (likely(baud && port->uartclk))
-                t = sci_scbrr_calc(s->cfg->scbrr_algo_id, baud, port->uartclk);
+        if (likely(baud && port->uartclk)) {
+                if (s->cfg->scbrr_algo_id == SCBRR_ALGO_6) {
+                        sci_baud_calc_hscif(baud, port->uartclk, &t, &srr,
+                                            &cks);
+                } else {
+                        t = sci_scbrr_calc(s->cfg->scbrr_algo_id, baud,
+                                           port->uartclk);
+                        for (cks = 0; t >= 256 && cks <= 3; cks++)
+                                t >>= 2;
+                }
+        }
 
         sci_port_enable(s);
 
@@ -1853,15 +1931,15 @@ static void sci_set_termios(struct uart_port *port, struct ktermios *termios,
 
         uart_update_timeout(port, termios->c_cflag, baud);
 
-        for (cks = 0; t >= 256 && cks <= 3; cks++)
-                t >>= 2;
-
         dev_dbg(port->dev, "%s: SMR %x, cks %x, t %x, SCSCR %x\n",
                 __func__, smr_val, cks, t, s->cfg->scscr);
 
         if (t >= 0) {
                 serial_port_out(port, SCSMR, (smr_val & ~3) | cks);
                 serial_port_out(port, SCBRR, t);
+                reg = sci_getreg(port, HSSRR);
+                if (reg->size)
+                        serial_port_out(port, HSSRR, srr | HSCIF_SRE);
                 udelay((1000000+(baud-1)) / baud); /* Wait one bit interval */
         } else
                 serial_port_out(port, SCSMR, smr_val);
@@ -1947,6 +2025,8 @@ static const char *sci_type(struct uart_port *port)
                 return "scifa";
         case PORT_SCIFB:
                 return "scifb";
+        case PORT_HSCIF:
+                return "hscif";
         }
 
         return NULL;
@@ -1960,7 +2040,10 @@ static inline unsigned long sci_port_size(struct uart_port *port)
          * from platform resource data at such a time that ports begin to
          * behave more erratically.
          */
-        return 64;
+        if (port->type == PORT_HSCIF)
+                return 96;
+        else
+                return 64;
 }
 
 static int sci_remap_port(struct uart_port *port)
@@ -2085,6 +2168,9 @@ static int sci_init_single(struct platform_device *dev,
         case PORT_SCIFB:
                 port->fifosize = 256;
                 break;
+        case PORT_HSCIF:
+                port->fifosize = 128;
+                break;
         case PORT_SCIFA:
                 port->fifosize = 64;
                 break;
@@ -2325,7 +2411,7 @@ static inline int sci_probe_earlyprintk(struct platform_device *pdev)
 #endif /* CONFIG_SERIAL_SH_SCI_CONSOLE */
 
 static char banner[] __initdata =
-        KERN_INFO "SuperH SCI(F) driver initialized\n";
+        KERN_INFO "SuperH (H)SCI(F) driver initialized\n";
 
 static struct uart_driver sci_uart_driver = {
         .owner          = THIS_MODULE,
@@ -2484,4 +2570,4 @@ module_exit(sci_exit);
 MODULE_LICENSE("GPL");
 MODULE_ALIAS("platform:sh-sci");
 MODULE_AUTHOR("Paul Mundt");
-MODULE_DESCRIPTION("SuperH SCI(F) serial driver");
+MODULE_DESCRIPTION("SuperH (H)SCI(F) serial driver");
diff --git a/include/linux/serial_sci.h b/include/linux/serial_sci.h
index eb763adf9815..d34049712a4d 100644
--- a/include/linux/serial_sci.h
+++ b/include/linux/serial_sci.h
@@ -5,7 +5,7 @@
 #include <linux/sh_dma.h>
 
 /*
- * Generic header for SuperH SCI(F) (used by sh/sh64/h8300 and related parts)
+ * Generic header for SuperH (H)SCI(F) (used by sh/sh64/h8300 and related parts)
  */
 
 #define SCIx_NOT_SUPPORTED      (-1)
@@ -16,6 +16,7 @@ enum {
         SCBRR_ALGO_3,           /* (((clk * 2) + 16 * bps) / (16 * bps) - 1) */
         SCBRR_ALGO_4,           /* (((clk * 2) + 16 * bps) / (32 * bps) - 1) */
         SCBRR_ALGO_5,           /* (((clk * 1000 / 32) / bps) - 1) */
+        SCBRR_ALGO_6,           /* HSCIF variable sample rate algorithm */
 };
 
 #define SCSCR_TIE       (1 << 7)
@@ -37,7 +38,7 @@ enum {
 
 #define SCI_DEFAULT_ERROR_MASK (SCI_PER | SCI_FER)
 
-/* SCxSR SCIF */
+/* SCxSR SCIF, HSCIF */
 #define SCIF_ER    0x0080
 #define SCIF_TEND  0x0040
 #define SCIF_TDFE  0x0020
@@ -55,6 +56,9 @@ enum {
 #define SCSPTR_SPB2IO   (1 << 1)
 #define SCSPTR_SPB2DT   (1 << 0)
 
+/* HSSRR HSCIF */
+#define HSCIF_SRE       0x8000
+
 /* Offsets into the sci_port->irqs array */
 enum {
         SCIx_ERI_IRQ,
@@ -90,6 +94,7 @@ enum {
         SCIx_SH4_SCIF_NO_SCSPTR_REGTYPE,
         SCIx_SH4_SCIF_FIFODATA_REGTYPE,
         SCIx_SH7705_SCIF_REGTYPE,
+        SCIx_HSCIF_REGTYPE,
 
         SCIx_NR_REGTYPES,
 };
@@ -115,6 +120,7 @@ enum {
         SCSMR, SCBRR, SCSCR, SCxSR,
         SCFCR, SCFDR, SCxTDR, SCxRDR,
         SCLSR, SCTFDR, SCRFDR, SCSPTR,
+        HSSRR,
 
         SCIx_NR_REGS,
 };
@@ -137,7 +143,7 @@ struct plat_sci_port {
         unsigned long   mapbase;                /* resource base */
         unsigned int    irqs[SCIx_NR_IRQS];     /* ERI, RXI, TXI, BRI */
         unsigned int    gpios[SCIx_NR_FNS];     /* SCK, RXD, TXD, CTS, RTS */
-        unsigned int    type;                   /* SCI / SCIF / IRDA */
+        unsigned int    type;                   /* SCI / SCIF / IRDA / HSCIF */
         upf_t           flags;                  /* UPF_* flags */
         unsigned long   capabilities;           /* Port features/capabilities */
 
diff --git a/include/uapi/linux/serial_core.h b/include/uapi/linux/serial_core.h
index 74c2bf7211f8..26eee07eeb24 100644
--- a/include/uapi/linux/serial_core.h
+++ b/include/uapi/linux/serial_core.h
@@ -226,4 +226,7 @@
 /* Rocketport EXPRESS/INFINITY */
 #define PORT_RP2        102
 
+/* SH-SCI */
+#define PORT_HSCIF      103
+
 #endif /* _UAPILINUX_SERIAL_CORE_H */