/*
* arch/ppc/boot/simple/mv64x60_tty.c
*
* Bootloader version of the embedded MPSC/UART driver for the Marvell 64x60.
* Note: Due to a GT64260A erratum, DMA will be used for UART input (via SDMA).
*
* Author: Mark A. Greer <mgreer@mvista.com>
*
* 2001 (c) MontaVista Software, Inc. This file is licensed under
* the terms of the GNU General Public License version 2. This program
* is licensed "as is" without any warranty of any kind, whether express
* or implied.
*/
/* This code assumes that the data cache has been disabled (L1, L2, L3). */
#include <linux/config.h>
#include <linux/types.h>
#include <linux/serial_reg.h>
#include <asm/serial.h>
#include <asm/io.h>
#include <asm/mv64x60_defs.h>
#include <mpsc_defs.h>
u32 mv64x60_console_baud = 9600;
u32 mv64x60_mpsc_clk_src = 8; /* TCLK */
u32 mv64x60_mpsc_clk_freq = 100000000;
extern void udelay(long);
static void stop_dma(int chan);
static void __iomem *mv64x60_base = (void __iomem *)CONFIG_MV64X60_NEW_BASE;
struct sdma_regs {
u32 sdc;
u32 sdcm;
u32 rx_desc;
u32 rx_buf_ptr;
u32 scrdp;
u32 tx_desc;
u32 sctdp;
u32 sftdp;
};
static struct sdma_regs sdma_regs[2];
#define SDMA_REGS_INIT(s, reg_base) { \
(s)->sdc = (reg_base) + SDMA_SDC; \
(s)->sdcm = (reg_base) + SDMA_SDCM; \
(s)->rx_desc = (reg_base) + SDMA_RX_DESC; \
(s)->rx_buf_ptr = (reg_base) + SDMA_RX_BUF_PTR; \
(s)->scrdp = (reg_base) + SDMA_SCRDP; \
(s)->tx_desc = (reg_base) + SDMA_TX_DESC; \
(s)->sctdp = (reg_base) + SDMA_SCTDP; \
(s)->sftdp = (reg_base) + SDMA_SFTDP; \
}
static u32 mpsc_base[2] = { MV64x60_MPSC_0_OFFSET, MV64x60_MPSC_1_OFFSET };
struct mv64x60_rx_desc {
u16 bufsize;
u16 bytecnt;
u32 cmd_stat;
u32 next_desc_ptr;
u32 buffer;
};
struct mv64x60_tx_desc {
u16 bytecnt;
u16 shadow;
u32 cmd_stat;
u32 next_desc_ptr;
u32 buffer;
};
#define MAX_RESET_WAIT 10000
#define MAX_TX_WAIT 10000
#define RX_NUM_DESC 2
#define TX_NUM_DESC 2
#define RX_BUF_SIZE 32
#define TX_BUF_SIZE 32
static struct mv64x60_rx_desc rd[2][RX_NUM_DESC] __attribute__ ((aligned(32)));
static struct mv64x60_tx_desc td[2][TX_NUM_DESC] __attribute__ ((aligned(32)));
static char rx_buf[2][RX_NUM_DESC * RX_BUF_SIZE] __attribute__ ((aligned(32)));
static char tx_buf[2][TX_NUM_DESC * TX_BUF_SIZE] __attribute__ ((aligned(32)));
static int cur_rd[2] = { 0, 0 };
static int cur_td[2] = { 0, 0 };
static char chan_initialized[2] = { 0, 0 };
#define RX_INIT_RDP(rdp) { \
(rdp)->bufsize = 2; \
(rdp)->bytecnt = 0; \
(rdp)->cmd_stat = SDMA_DESC_CMDSTAT_L | SDMA_DESC_CMDSTAT_F | \
SDMA_DESC_CMDSTAT_O; \
}
#ifdef CONFIG_MV64360
static u32 cpu2mem_tab[MV64x60_CPU2MEM_WINDOWS][2] = {
{ MV64x60_CPU2MEM_0_BASE, MV64x60_CPU2MEM_0_SIZE },
{ MV64x60_CPU2MEM_1_BASE, MV64x60_CPU2MEM_1_SIZE },
{ MV64x60_CPU2MEM_2_BASE, MV64x60_CPU2MEM_2_SIZE },
{ MV64x60_CPU2MEM_3_BASE, MV64x60_CPU2MEM_3_SIZE }
};
static u32 com2mem_tab[MV64x60_CPU2MEM_WINDOWS][2] = {
{ MV64360_MPSC2MEM_0_BASE, MV64360_MPSC2MEM_0_SIZE },
{ MV64360_MPSC2MEM_1_BASE, MV64360_MPSC2MEM_1_SIZE },
{ MV64360_MPSC2MEM_2_BASE, MV64360_MPSC2MEM_2_SIZE },
{ MV64360_MPSC2MEM_3_BASE, MV64360_MPSC2MEM_3_SIZE }
};
static u32 dram_selects[MV64x60_CPU2MEM_WINDOWS] = { 0xe, 0xd, 0xb, 0x7 };
#endif
unsigned long
serial_init(int chan, void *ignored)
{
u32 mpsc_routing_base, sdma_base, brg_bcr, cdv;
int i;
chan = (chan == 1); /* default to chan 0 if anything but 1 */
if (chan_initialized[chan])
return chan;
chan_initialized[chan] = 1;
if (chan == 0) {
sdma_base = MV64x60_SDMA_0_OFFSET;
brg_bcr = MV64x60_BRG_0_OFFSET + BRG_BCR;
SDMA_REGS_INIT(&sdma_regs[0], MV64x60_SDMA_0_OFFSET);
} else {
sdma_base = MV64x60_SDMA_1_OFFSET;
brg_bcr = MV64x60_BRG_1_OFFSET + BRG_BCR;
SDMA_REGS_INIT(&sdma_regs[0], MV64x60_SDMA_1_OFFSET);
}
mpsc_routing_base = MV64x60_MPSC_ROUTING_OFFSET;
stop_dma(chan);
/* Set up ring buffers */
for (i=0; i<RX_NUM_DESC; i++) {
RX_INIT_RDP(&rd[chan][i]);
rd[chan][i].buffer = (u32)&rx_buf[chan][i * RX_BUF_SIZE];
rd[chan][i].next_desc_ptr = (u32)&rd[chan][i+1];
}
rd[chan][RX_NUM_DESC - 1].next_desc_ptr = (u32)&rd[chan][0];
for (i=0; i<TX_NUM_DESC; i++) {
td[chan][i].bytecnt = 0;
td[chan][i].shadow = 0;
td[chan][i].buffer = (u32)&tx_buf[chan][i * TX_BUF_SIZE];
td[chan][i].cmd_stat = SDMA_DESC_CMDSTAT_F|SDMA_DESC_CMDSTAT_L;
td[chan][i].next_desc_ptr = (u32)&td[chan][i+1];
}
td[chan][TX_NUM_DESC - 1].next_desc_ptr = (u32)&td[chan][0];
/* Set MPSC Routing */
out_le32(mv64x60_base + mpsc_routing_base + MPSC_MRR, 0x3ffffe38);
#ifdef CONFIG_GT64260
out_le32(mv64x60_base + GT64260_MPP_SERIAL_PORTS_MULTIPLEX, 0x00001102);
#else /* Must be MV64360 or MV64460 */
{
u32 enables, prot_bits, v;
/* Set up comm unit to memory mapping windows */
/* Note: Assumes MV64x60_CPU2MEM_WINDOWS == 4 */
enables = in_le32(mv64x60_base + MV64360_CPU_BAR_ENABLE) & 0xf;
prot_bits = 0;
for (i=0; i<MV64x60_CPU2MEM_WINDOWS; i++) {
if (!(enables & (1 << i))) {
v = in_le32(mv64x60_base + cpu2mem_tab[i][0]);
v = ((v & 0xffff) << 16) | (dram_selects[i] << 8);
out_le32(mv64x60_base + com2mem_tab[i][0], v);
v = in_le32(mv64x60_base + cpu2mem_tab[i][1]);
v = (v & 0xffff) << 16;
out_le32(mv64x60_base + com2mem_tab[i][1], v);
prot_bits |= (0x3 << (i << 1)); /* r/w access */
}
}
out_le32(mv64x60_base + MV64360_MPSC_0_REMAP, 0);
out_le32(mv64x60_base + MV64360_MPSC_1_REMAP, 0);
out_le32(mv64x60_base + MV64360_MPSC2MEM_ACC_PROT_0, prot_bits);
out_le32(mv64x60_base + MV64360_MPSC2MEM_ACC_PROT_1, prot_bits);
out_le32(mv64x60_base + MV64360_MPSC2MEM_BAR_ENABLE, enables);
}
#endif
/* MPSC 0/1 Rx & Tx get clocks BRG0/1 */
out_le32(mv64x60_base + mpsc_routing_base + MPSC_RCRR, 0x00000100);
out_le32(mv64x60_base + mpsc_routing_base + MPSC_TCRR, 0x00000100);
/* clear pending interrupts */
out_le32(mv64x60_base + MV64x60_SDMA_INTR_OFFSET + SDMA_INTR_MASK, 0);
out_le32(mv64x60_base + SDMA_SCRDP + sdma_base, (int)&rd[chan][0]);
out_le32(mv64x60_base + SDMA_SCTDP + sdma_base,
(int)&td[chan][TX_NUM_DESC - 1]);
out_le32(mv64x60_base + SDMA_SFTDP + sdma_base,
(int)&td[chan][TX_NUM_DESC - 1]);
out_le32(mv64x60_base + SDMA_SDC + sdma_base,
SDMA_SDC_RFT | SDMA_SDC_SFM | SDMA_SDC_BLMR | SDMA_SDC_BLMT |
(3 << 12));
cdv = ((mv64x60_mpsc_clk_freq/(32*mv64x60_console_baud))-1);
out_le32(mv64x60_base + brg_bcr,
((mv64x60_mpsc_clk_src << 18) | (1 << 16) | cdv));
/* Put MPSC into UART mode, no null modem, 16x clock mode */
out_le32(mv64x60_base + MPSC_MMCRL + mpsc_base[chan], 0x000004c4);
out_le32(mv64x60_base + MPSC_MMCRH + mpsc_base[chan], 0x04400400);
out_le32(mv64x60_base + MPSC_CHR_1 + mpsc_base[chan], 0);
out_le32(mv64x60_base + MPSC_CHR_9 + mpsc_base[chan], 0);
out_le32(mv64x60_base + MPSC_CHR_10 + mpsc_base[chan], 0);
out_le32(mv64x60_base + MPSC_CHR_3 + mpsc_base[chan], 4);
out_le32(mv64x60_base + MPSC_CHR_4 + mpsc_base[chan], 0);
out_le32(mv64x60_base + MPSC_CHR_5 + mpsc_base[chan], 0);
out_le32(mv64x60_base + MPSC_CHR_6 + mpsc_base[chan], 0);
out_le32(mv64x60_base + MPSC_CHR_7 + mpsc_base[chan], 0);
out_le32(mv64x60_base + MPSC_CHR_8 + mpsc_base[chan], 0);
/* 8 data bits, 1 stop bit */
out_le32(mv64x60_base + MPSC_MPCR + mpsc_base[chan], (3 << 12));
out_le32(mv64x60_base + SDMA_SDCM + sdma_base, SDMA_SDCM_ERD);
out_le32(mv64x60_base + MPSC_CHR_2 + mpsc_base[chan], MPSC_CHR_2_EH);
udelay(100);
return chan;
}
static void
stop_dma(int chan)
{
int i;
/* Abort MPSC Rx (aborting Tx messes things up) */
out_le32(mv64x60_base + MPSC_CHR_2 + mpsc_base[chan], MPSC_CHR_2_RA);
/* Abort SDMA Rx, Tx */
out_le32(mv64x60_base + sdma_regs[chan].sdcm,
SDMA_SDCM_AR | SDMA_SDCM_STD);
for (i=0; i<MAX_RESET_WAIT; i++) {
if ((in_le32(mv64x60_base + sdma_regs[chan].sdcm) &
(SDMA_SDCM_AR | SDMA_SDCM_AT)) == 0)
break;
udelay(100);
}
}
static int
wait_for_ownership(int chan)
{
int i;
for (i=0; i<MAX_TX_WAIT; i++) {
if ((in_le32(mv64x60_base + sdma_regs[chan].sdcm) &
SDMA_SDCM_TXD) == 0)
break;
udelay(1000);
}
return (i < MAX_TX_WAIT);
}
void
serial_putc(unsigned long com_port, unsigned char c)
{
struct mv64x60_tx_desc *tdp;
if (wait_for_ownership(com_port) == 0)
return;
tdp = &td[com_port][cur_td[com_port]];
if (++cur_td[com_port] >= TX_NUM_DESC)
cur_td[com_port] = 0;
*(unchar *)(tdp->buffer ^ 7) = c;
tdp->bytecnt = 1;
tdp->shadow = 1;
tdp->cmd_stat = SDMA_DESC_CMDSTAT_L | SDMA_DESC_CMDSTAT_F |
SDMA_DESC_CMDSTAT_O;
out_le32(mv64x60_base + sdma_regs[com_port].sctdp, (int)tdp);
out_le32(mv64x60_base + sdma_regs[com_port].sftdp, (int)tdp);
out_le32(mv64x60_base + sdma_regs[com_port].sdcm,
in_le32(mv64x60_base + sdma_regs[com_port].sdcm) |
SDMA_SDCM_TXD);
}
unsigned char
serial_getc(unsigned long com_port)
{
struct mv64x60_rx_desc *rdp;
unchar c = '\0';
rdp = &rd[com_port][cur_rd[com_port]];
if ((rdp->cmd_stat & (SDMA_DESC_CMDSTAT_O|SDMA_DESC_CMDSTAT_ES)) == 0) {
c = *(unchar *)(rdp->buffer ^ 7);
RX_INIT_RDP(rdp);
if (++cur_rd[com_port] >= RX_NUM_DESC)
cur_rd[com_port] = 0;
}
return c;
}
int
serial_tstc(unsigned long com_port)
{
struct mv64x60_rx_desc *rdp;
int loop_count = 0;
int rc = 0;
rdp = &rd[com_port][cur_rd[com_port]];
/* Go thru rcv desc's until empty looking for one with data (no error)*/
while (((rdp->cmd_stat & SDMA_DESC_CMDSTAT_O) == 0) &&
(loop_count++ < RX_NUM_DESC)) {
/* If there was an error, reinit the desc & continue */
if ((rdp->cmd_stat & SDMA_DESC_CMDSTAT_ES) != 0) {
RX_INIT_RDP(rdp);
if (++cur_rd[com_port] >= RX_NUM_DESC)
cur_rd[com_port] = 0;
rdp = (struct mv64x60_rx_desc *)rdp->next_desc_ptr;
} else {
rc = 1;
break;
}
}
return rc;
}
void
serial_close(unsigned long com_port)
{
stop_dma(com_port);
}
