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-rw-r--r--drivers/char/scc.h613
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diff --git a/drivers/char/scc.h b/drivers/char/scc.h
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--- /dev/null
+++ b/drivers/char/scc.h
@@ -0,0 +1,613 @@
+/*
+ * atari_SCC.h: Definitions for the Am8530 Serial Communications Controller
+ *
+ * Copyright 1994 Roman Hodek <Roman.Hodek@informatik.uni-erlangen.de>
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file COPYING in the main directory of this archive
+ * for more details.
+ *
+ */
+
+
+#ifndef _SCC_H
+#define _SCC_H
+
+#include <linux/delay.h>
+
+/* Special configuration ioctls for the Atari SCC5380 Serial
+ * Communications Controller
+ */
+
+/* ioctl command codes */
+
+#define TIOCGATSCC 0x54c0 /* get SCC configuration */
+#define TIOCSATSCC 0x54c1 /* set SCC configuration */
+#define TIOCDATSCC 0x54c2 /* reset configuration to defaults */
+
+/* Clock sources */
+
+#define CLK_RTxC 0
+#define CLK_TRxC 1
+#define CLK_PCLK 2
+
+/* baud_bases for the common clocks in the Atari. These are the real
+ * frequencies divided by 16.
+ */
+
+#define SCC_BAUD_BASE_TIMC 19200 /* 0.3072 MHz from TT-MFP, Timer C */
+#define SCC_BAUD_BASE_BCLK 153600 /* 2.4576 MHz */
+#define SCC_BAUD_BASE_PCLK4 229500 /* 3.6720 MHz */
+#define SCC_BAUD_BASE_PCLK 503374 /* 8.0539763 MHz */
+#define SCC_BAUD_BASE_NONE 0 /* for not connected or unused
+ * clock sources */
+
+/* The SCC clock configuration structure */
+
+struct scc_clock_config {
+ unsigned RTxC_base; /* base_baud of RTxC */
+ unsigned TRxC_base; /* base_baud of TRxC */
+ unsigned PCLK_base; /* base_baud of PCLK, both channels! */
+ struct {
+ unsigned clksrc; /* CLK_RTxC, CLK_TRxC or CLK_PCLK */
+ unsigned divisor; /* divisor for base baud, valid values:
+ * see below */
+ } baud_table[17]; /* For 50, 75, 110, 135, 150, 200, 300,
+ * 600, 1200, 1800, 2400, 4800, 9600,
+ * 19200, 38400, 57600 and 115200 bps.
+ * The last two could be replaced by
+ * other rates > 38400 if they're not
+ * possible.
+ */
+};
+
+/* The following divisors are valid:
+ *
+ * - CLK_RTxC: 1 or even (1, 2 and 4 are the direct modes, > 4 use
+ * the BRG)
+ *
+ * - CLK_TRxC: 1, 2 or 4 (no BRG, only direct modes possible)
+ *
+ * - CLK_PCLK: >= 4 and even (no direct modes, only BRG)
+ *
+ */
+
+struct scc_port {
+ struct gs_port gs;
+ volatile unsigned char *ctrlp;
+ volatile unsigned char *datap;
+ int x_char; /* xon/xoff character */
+ int c_dcd;
+ int channel;
+ struct scc_port *port_a; /* Reference to port A and B */
+ struct scc_port *port_b; /* structs for reg access */
+};
+
+#define SCC_MAGIC 0x52696368
+
+/***********************************************************************/
+/* */
+/* Register Names */
+/* */
+/***********************************************************************/
+
+/* The SCC documentation gives no explicit names to the registers,
+ * they're just called WR0..15 and RR0..15. To make the source code
+ * better readable and make the transparent write reg read access (see
+ * below) possible, I christen them here with self-invented names.
+ * Note that (real) read registers are assigned numbers 16..31. WR7'
+ * has number 33.
+ */
+
+#define COMMAND_REG 0 /* wo */
+#define INT_AND_DMA_REG 1 /* wo */
+#define INT_VECTOR_REG 2 /* rw, common to both channels */
+#define RX_CTRL_REG 3 /* rw */
+#define AUX1_CTRL_REG 4 /* rw */
+#define TX_CTRL_REG 5 /* rw */
+#define SYNC_ADR_REG 6 /* wo */
+#define SYNC_CHAR_REG 7 /* wo */
+#define SDLC_OPTION_REG 33 /* wo */
+#define TX_DATA_REG 8 /* wo */
+#define MASTER_INT_CTRL 9 /* wo, common to both channels */
+#define AUX2_CTRL_REG 10 /* rw */
+#define CLK_CTRL_REG 11 /* wo */
+#define TIMER_LOW_REG 12 /* rw */
+#define TIMER_HIGH_REG 13 /* rw */
+#define DPLL_CTRL_REG 14 /* wo */
+#define INT_CTRL_REG 15 /* rw */
+
+#define STATUS_REG 16 /* ro */
+#define SPCOND_STATUS_REG 17 /* wo */
+/* RR2 is WR2 for Channel A, Channel B gives vector + current status: */
+#define CURR_VECTOR_REG 18 /* Ch. B only, Ch. A for rw */
+#define INT_PENDING_REG 19 /* Channel A only! */
+/* RR4 is WR4, if b6(MR7') == 1 */
+/* RR5 is WR5, if b6(MR7') == 1 */
+#define FS_FIFO_LOW_REG 22 /* ro */
+#define FS_FIFO_HIGH_REG 23 /* ro */
+#define RX_DATA_REG 24 /* ro */
+/* RR9 is WR3, if b6(MR7') == 1 */
+#define DPLL_STATUS_REG 26 /* ro */
+/* RR11 is WR10, if b6(MR7') == 1 */
+/* RR12 is WR12 */
+/* RR13 is WR13 */
+/* RR14 not present */
+/* RR15 is WR15 */
+
+
+/***********************************************************************/
+/* */
+/* Register Values */
+/* */
+/***********************************************************************/
+
+
+/* WR0: COMMAND_REG "CR" */
+
+#define CR_RX_CRC_RESET 0x40
+#define CR_TX_CRC_RESET 0x80
+#define CR_TX_UNDERRUN_RESET 0xc0
+
+#define CR_EXTSTAT_RESET 0x10
+#define CR_SEND_ABORT 0x18
+#define CR_ENAB_INT_NEXT_RX 0x20
+#define CR_TX_PENDING_RESET 0x28
+#define CR_ERROR_RESET 0x30
+#define CR_HIGHEST_IUS_RESET 0x38
+
+
+/* WR1: INT_AND_DMA_REG "IDR" */
+
+#define IDR_EXTSTAT_INT_ENAB 0x01
+#define IDR_TX_INT_ENAB 0x02
+#define IDR_PARERR_AS_SPCOND 0x04
+
+#define IDR_RX_INT_DISAB 0x00
+#define IDR_RX_INT_FIRST 0x08
+#define IDR_RX_INT_ALL 0x10
+#define IDR_RX_INT_SPCOND 0x18
+#define IDR_RX_INT_MASK 0x18
+
+#define IDR_WAITREQ_RX 0x20
+#define IDR_WAITREQ_IS_REQ 0x40
+#define IDR_WAITREQ_ENAB 0x80
+
+
+/* WR3: RX_CTRL_REG "RCR" */
+
+#define RCR_RX_ENAB 0x01
+#define RCR_DISCARD_SYNC_CHARS 0x02
+#define RCR_ADDR_SEARCH 0x04
+#define RCR_CRC_ENAB 0x08
+#define RCR_SEARCH_MODE 0x10
+#define RCR_AUTO_ENAB_MODE 0x20
+
+#define RCR_CHSIZE_MASK 0xc0
+#define RCR_CHSIZE_5 0x00
+#define RCR_CHSIZE_6 0x40
+#define RCR_CHSIZE_7 0x80
+#define RCR_CHSIZE_8 0xc0
+
+
+/* WR4: AUX1_CTRL_REG "A1CR" */
+
+#define A1CR_PARITY_MASK 0x03
+#define A1CR_PARITY_NONE 0x00
+#define A1CR_PARITY_ODD 0x01
+#define A1CR_PARITY_EVEN 0x03
+
+#define A1CR_MODE_MASK 0x0c
+#define A1CR_MODE_SYNCR 0x00
+#define A1CR_MODE_ASYNC_1 0x04
+#define A1CR_MODE_ASYNC_15 0x08
+#define A1CR_MODE_ASYNC_2 0x0c
+
+#define A1CR_SYNCR_MODE_MASK 0x30
+#define A1CR_SYNCR_MONOSYNC 0x00
+#define A1CR_SYNCR_BISYNC 0x10
+#define A1CR_SYNCR_SDLC 0x20
+#define A1CR_SYNCR_EXTCSYNC 0x30
+
+#define A1CR_CLKMODE_MASK 0xc0
+#define A1CR_CLKMODE_x1 0x00
+#define A1CR_CLKMODE_x16 0x40
+#define A1CR_CLKMODE_x32 0x80
+#define A1CR_CLKMODE_x64 0xc0
+
+
+/* WR5: TX_CTRL_REG "TCR" */
+
+#define TCR_TX_CRC_ENAB 0x01
+#define TCR_RTS 0x02
+#define TCR_USE_CRC_CCITT 0x00
+#define TCR_USE_CRC_16 0x04
+#define TCR_TX_ENAB 0x08
+#define TCR_SEND_BREAK 0x10
+
+#define TCR_CHSIZE_MASK 0x60
+#define TCR_CHSIZE_5 0x00
+#define TCR_CHSIZE_6 0x20
+#define TCR_CHSIZE_7 0x40
+#define TCR_CHSIZE_8 0x60
+
+#define TCR_DTR 0x80
+
+
+/* WR7': SLDC_OPTION_REG "SOR" */
+
+#define SOR_AUTO_TX_ENAB 0x01
+#define SOR_AUTO_EOM_RESET 0x02
+#define SOR_AUTO_RTS_MODE 0x04
+#define SOR_NRZI_DISAB_HIGH 0x08
+#define SOR_ALT_DTRREQ_TIMING 0x10
+#define SOR_READ_CRC_CHARS 0x20
+#define SOR_EXTENDED_REG_ACCESS 0x40
+
+
+/* WR9: MASTER_INT_CTRL "MIC" */
+
+#define MIC_VEC_INCL_STAT 0x01
+#define MIC_NO_VECTOR 0x02
+#define MIC_DISAB_LOWER_CHAIN 0x04
+#define MIC_MASTER_INT_ENAB 0x08
+#define MIC_STATUS_HIGH 0x10
+#define MIC_IGN_INTACK 0x20
+
+#define MIC_NO_RESET 0x00
+#define MIC_CH_A_RESET 0x40
+#define MIC_CH_B_RESET 0x80
+#define MIC_HARD_RESET 0xc0
+
+
+/* WR10: AUX2_CTRL_REG "A2CR" */
+
+#define A2CR_SYNC_6 0x01
+#define A2CR_LOOP_MODE 0x02
+#define A2CR_ABORT_ON_UNDERRUN 0x04
+#define A2CR_MARK_IDLE 0x08
+#define A2CR_GO_ACTIVE_ON_POLL 0x10
+
+#define A2CR_CODING_MASK 0x60
+#define A2CR_CODING_NRZ 0x00
+#define A2CR_CODING_NRZI 0x20
+#define A2CR_CODING_FM1 0x40
+#define A2CR_CODING_FM0 0x60
+
+#define A2CR_PRESET_CRC_1 0x80
+
+
+/* WR11: CLK_CTRL_REG "CCR" */
+
+#define CCR_TRxCOUT_MASK 0x03
+#define CCR_TRxCOUT_XTAL 0x00
+#define CCR_TRxCOUT_TXCLK 0x01
+#define CCR_TRxCOUT_BRG 0x02
+#define CCR_TRxCOUT_DPLL 0x03
+
+#define CCR_TRxC_OUTPUT 0x04
+
+#define CCR_TXCLK_MASK 0x18
+#define CCR_TXCLK_RTxC 0x00
+#define CCR_TXCLK_TRxC 0x08
+#define CCR_TXCLK_BRG 0x10
+#define CCR_TXCLK_DPLL 0x18
+
+#define CCR_RXCLK_MASK 0x60
+#define CCR_RXCLK_RTxC 0x00
+#define CCR_RXCLK_TRxC 0x20
+#define CCR_RXCLK_BRG 0x40
+#define CCR_RXCLK_DPLL 0x60
+
+#define CCR_RTxC_XTAL 0x80
+
+
+/* WR14: DPLL_CTRL_REG "DCR" */
+
+#define DCR_BRG_ENAB 0x01
+#define DCR_BRG_USE_PCLK 0x02
+#define DCR_DTRREQ_IS_REQ 0x04
+#define DCR_AUTO_ECHO 0x08
+#define DCR_LOCAL_LOOPBACK 0x10
+
+#define DCR_DPLL_EDGE_SEARCH 0x20
+#define DCR_DPLL_ERR_RESET 0x40
+#define DCR_DPLL_DISAB 0x60
+#define DCR_DPLL_CLK_BRG 0x80
+#define DCR_DPLL_CLK_RTxC 0xa0
+#define DCR_DPLL_FM 0xc0
+#define DCR_DPLL_NRZI 0xe0
+
+
+/* WR15: INT_CTRL_REG "ICR" */
+
+#define ICR_OPTIONREG_SELECT 0x01
+#define ICR_ENAB_BRG_ZERO_INT 0x02
+#define ICR_USE_FS_FIFO 0x04
+#define ICR_ENAB_DCD_INT 0x08
+#define ICR_ENAB_SYNC_INT 0x10
+#define ICR_ENAB_CTS_INT 0x20
+#define ICR_ENAB_UNDERRUN_INT 0x40
+#define ICR_ENAB_BREAK_INT 0x80
+
+
+/* RR0: STATUS_REG "SR" */
+
+#define SR_CHAR_AVAIL 0x01
+#define SR_BRG_ZERO 0x02
+#define SR_TX_BUF_EMPTY 0x04
+#define SR_DCD 0x08
+#define SR_SYNC_ABORT 0x10
+#define SR_CTS 0x20
+#define SR_TX_UNDERRUN 0x40
+#define SR_BREAK 0x80
+
+
+/* RR1: SPCOND_STATUS_REG "SCSR" */
+
+#define SCSR_ALL_SENT 0x01
+#define SCSR_RESIDUAL_MASK 0x0e
+#define SCSR_PARITY_ERR 0x10
+#define SCSR_RX_OVERRUN 0x20
+#define SCSR_CRC_FRAME_ERR 0x40
+#define SCSR_END_OF_FRAME 0x80
+
+
+/* RR3: INT_PENDING_REG "IPR" */
+
+#define IPR_B_EXTSTAT 0x01
+#define IPR_B_TX 0x02
+#define IPR_B_RX 0x04
+#define IPR_A_EXTSTAT 0x08
+#define IPR_A_TX 0x10
+#define IPR_A_RX 0x20
+
+
+/* RR7: FS_FIFO_HIGH_REG "FFHR" */
+
+#define FFHR_CNT_MASK 0x3f
+#define FFHR_IS_FROM_FIFO 0x40
+#define FFHR_FIFO_OVERRUN 0x80
+
+
+/* RR10: DPLL_STATUS_REG "DSR" */
+
+#define DSR_ON_LOOP 0x02
+#define DSR_ON_LOOP_SENDING 0x10
+#define DSR_TWO_CLK_MISSING 0x40
+#define DSR_ONE_CLK_MISSING 0x80
+
+/***********************************************************************/
+/* */
+/* Register Access */
+/* */
+/***********************************************************************/
+
+
+/* The SCC needs 3.5 PCLK cycles recovery time between to register
+ * accesses. PCLK runs with 8 MHz on an Atari, so this delay is 3.5 *
+ * 125 ns = 437.5 ns. This is too short for udelay().
+ * 10/16/95: A tstb mfp.par_dt_reg takes 600ns (sure?) and thus should be
+ * quite right
+ */
+
+#define scc_reg_delay() \
+ do { \
+ if (MACH_IS_MVME16x || MACH_IS_BVME6000 || MACH_IS_MVME147) \
+ __asm__ __volatile__ ( " nop; nop"); \
+ else if (MACH_IS_ATARI) \
+ __asm__ __volatile__ ( "tstb %0" : : "g" (*_scc_del) : "cc" );\
+ } while (0)
+
+extern unsigned char scc_shadow[2][16];
+
+/* The following functions should relax the somehow complicated
+ * register access of the SCC. _SCCwrite() stores all written values
+ * (except for WR0 and WR8) in shadow registers for later recall. This
+ * removes the burden of remembering written values as needed. The
+ * extra work of storing the value doesn't count, since a delay is
+ * needed after a SCC access anyway. Additionally, _SCCwrite() manages
+ * writes to WR0 and WR8 differently, because these can be accessed
+ * directly with less overhead. Another special case are WR7 and WR7'.
+ * _SCCwrite automatically checks what of this registers is selected
+ * and changes b0 of WR15 if needed.
+ *
+ * _SCCread() for standard read registers is straightforward, except
+ * for RR2 (split into two "virtual" registers: one for the value
+ * written to WR2 (from the shadow) and one for the vector including
+ * status from RR2, Ch. B) and RR3. The latter must be read from
+ * Channel A, because it reads as all zeros on Ch. B. RR0 and RR8 can
+ * be accessed directly as before.
+ *
+ * The two inline function contain complicated switch statements. But
+ * I rely on regno and final_delay being constants, so gcc can reduce
+ * the whole stuff to just some assembler statements.
+ *
+ * _SCCwrite and _SCCread aren't intended to be used directly under
+ * normal circumstances. The macros SCCread[_ND] and SCCwrite[_ND] are
+ * for that purpose. They assume that a local variable 'port' is
+ * declared and pointing to the port's scc_struct entry. The
+ * variants with "_NB" appended should be used if no other SCC
+ * accesses follow immediately (within 0.5 usecs). They just skip the
+ * final delay nops.
+ *
+ * Please note that accesses to SCC registers should only take place
+ * when interrupts are turned off (at least if SCC interrupts are
+ * enabled). Otherwise, an interrupt could interfere with the
+ * two-stage accessing process.
+ *
+ */
+
+
+static __inline__ void _SCCwrite(
+ struct scc_port *port,
+ unsigned char *shadow,
+ volatile unsigned char *_scc_del,
+ int regno,
+ unsigned char val, int final_delay )
+{
+ switch( regno ) {
+
+ case COMMAND_REG:
+ /* WR0 can be written directly without pointing */
+ *port->ctrlp = val;
+ break;
+
+ case SYNC_CHAR_REG:
+ /* For WR7, first set b0 of WR15 to 0, if needed */
+ if (shadow[INT_CTRL_REG] & ICR_OPTIONREG_SELECT) {
+ *port->ctrlp = 15;
+ shadow[INT_CTRL_REG] &= ~ICR_OPTIONREG_SELECT;
+ scc_reg_delay();
+ *port->ctrlp = shadow[INT_CTRL_REG];
+ scc_reg_delay();
+ }
+ goto normal_case;
+
+ case SDLC_OPTION_REG:
+ /* For WR7', first set b0 of WR15 to 1, if needed */
+ if (!(shadow[INT_CTRL_REG] & ICR_OPTIONREG_SELECT)) {
+ *port->ctrlp = 15;
+ shadow[INT_CTRL_REG] |= ICR_OPTIONREG_SELECT;
+ scc_reg_delay();
+ *port->ctrlp = shadow[INT_CTRL_REG];
+ scc_reg_delay();
+ }
+ *port->ctrlp = 7;
+ shadow[8] = val; /* WR7' shadowed at WR8 */
+ scc_reg_delay();
+ *port->ctrlp = val;
+ break;
+
+ case TX_DATA_REG: /* WR8 */
+ /* TX_DATA_REG can be accessed directly on some h/w */
+ if (MACH_IS_MVME16x || MACH_IS_BVME6000 || MACH_IS_MVME147)
+ {
+ *port->ctrlp = regno;
+ scc_reg_delay();
+ *port->ctrlp = val;
+ }
+ else
+ *port->datap = val;
+ break;
+
+ case MASTER_INT_CTRL:
+ *port->ctrlp = regno;
+ val &= 0x3f; /* bits 6..7 are the reset commands */
+ scc_shadow[0][regno] = val;
+ scc_reg_delay();
+ *port->ctrlp = val;
+ break;
+
+ case DPLL_CTRL_REG:
+ *port->ctrlp = regno;
+ val &= 0x1f; /* bits 5..7 are the DPLL commands */
+ shadow[regno] = val;
+ scc_reg_delay();
+ *port->ctrlp = val;
+ break;
+
+ case 1 ... 6:
+ case 10 ... 13:
+ case 15:
+ normal_case:
+ *port->ctrlp = regno;
+ shadow[regno] = val;
+ scc_reg_delay();
+ *port->ctrlp = val;
+ break;
+
+ default:
+ printk( "Bad SCC write access to WR%d\n", regno );
+ break;
+
+ }
+
+ if (final_delay)
+ scc_reg_delay();
+}
+
+
+static __inline__ unsigned char _SCCread(
+ struct scc_port *port,
+ unsigned char *shadow,
+ volatile unsigned char *_scc_del,
+ int regno, int final_delay )
+{
+ unsigned char rv;
+
+ switch( regno ) {
+
+ /* --- real read registers --- */
+ case STATUS_REG:
+ rv = *port->ctrlp;
+ break;
+
+ case INT_PENDING_REG:
+ /* RR3: read only from Channel A! */
+ port = port->port_a;
+ goto normal_case;
+
+ case RX_DATA_REG:
+ /* RR8 can be accessed directly on some h/w */
+ if (MACH_IS_MVME16x || MACH_IS_BVME6000 || MACH_IS_MVME147)
+ {
+ *port->ctrlp = 8;
+ scc_reg_delay();
+ rv = *port->ctrlp;
+ }
+ else
+ rv = *port->datap;
+ break;
+
+ case CURR_VECTOR_REG:
+ /* RR2 (vector including status) from Ch. B */
+ port = port->port_b;
+ goto normal_case;
+
+ /* --- reading write registers: access the shadow --- */
+ case 1 ... 7:
+ case 10 ... 15:
+ return shadow[regno]; /* no final delay! */
+
+ /* WR7' is special, because it is shadowed at the place of WR8 */
+ case SDLC_OPTION_REG:
+ return shadow[8]; /* no final delay! */
+
+ /* WR9 is special too, because it is common for both channels */
+ case MASTER_INT_CTRL:
+ return scc_shadow[0][9]; /* no final delay! */
+
+ default:
+ printk( "Bad SCC read access to %cR%d\n", (regno & 16) ? 'R' : 'W',
+ regno & ~16 );
+ break;
+
+ case SPCOND_STATUS_REG:
+ case FS_FIFO_LOW_REG:
+ case FS_FIFO_HIGH_REG:
+ case DPLL_STATUS_REG:
+ normal_case:
+ *port->ctrlp = regno & 0x0f;
+ scc_reg_delay();
+ rv = *port->ctrlp;
+ break;
+
+ }
+
+ if (final_delay)
+ scc_reg_delay();
+ return rv;
+}
+
+#define SCC_ACCESS_INIT(port) \
+ unsigned char *_scc_shadow = &scc_shadow[port->channel][0]
+
+#define SCCwrite(reg,val) _SCCwrite(port,_scc_shadow,scc_del,(reg),(val),1)
+#define SCCwrite_NB(reg,val) _SCCwrite(port,_scc_shadow,scc_del,(reg),(val),0)
+#define SCCread(reg) _SCCread(port,_scc_shadow,scc_del,(reg),1)
+#define SCCread_NB(reg) _SCCread(port,_scc_shadow,scc_del,(reg),0)
+
+#define SCCmod(reg,and,or) SCCwrite((reg),(SCCread(reg)&(and))|(or))
+
+#endif /* _SCC_H */
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