SH4: Serial controller improvement

Add receive character feature to SH4 SCIF.
SH4-SCI feature implementation work is left.

(Shin-ichiro KAWASAKI)

git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@5221 c046a42c-6fe2-441c-8c8c-71466251a162
This commit is contained in:
aurel32 2008-09-15 07:05:18 +00:00
parent f24f381b2d
commit 63242a007a

View file

@ -37,6 +37,8 @@
#define SH_SERIAL_FLAG_BRK (1 << 3)
#define SH_SERIAL_FLAG_DR (1 << 4)
#define SH_RX_FIFO_LENGTH (16)
typedef struct {
uint8_t smr;
uint8_t brr;
@ -46,13 +48,16 @@ typedef struct {
uint16_t fcr;
uint8_t sptr;
uint8_t rx_fifo[16]; /* frdr / rdr */
uint8_t rx_fifo[SH_RX_FIFO_LENGTH]; /* frdr / rdr */
uint8_t rx_cnt;
uint8_t rx_tail;
uint8_t rx_head;
target_phys_addr_t base;
int freq;
int feat;
int flags;
int rtrg;
CharDriverState *chr;
@ -63,6 +68,14 @@ typedef struct {
struct intc_source *bri;
} sh_serial_state;
static void sh_serial_clear_fifo(sh_serial_state * s)
{
memset(s->rx_fifo, 0, SH_RX_FIFO_LENGTH);
s->rx_cnt = 0;
s->rx_head = 0;
s->rx_tail = 0;
}
static void sh_serial_ioport_write(void *opaque, uint32_t offs, uint32_t val)
{
sh_serial_state *s = opaque;
@ -80,6 +93,7 @@ static void sh_serial_ioport_write(void *opaque, uint32_t offs, uint32_t val)
s->brr = val;
return;
case 0x08: /* SCR */
/* TODO : For SH7751, SCIF mask should be 0xfb. */
s->scr = val & ((s->feat & SH_SERIAL_FEAT_SCIF) ? 0xfa : 0xff);
if (!(val & (1 << 5)))
s->flags |= SH_SERIAL_FLAG_TEND;
@ -89,6 +103,9 @@ static void sh_serial_ioport_write(void *opaque, uint32_t offs, uint32_t val)
else if (!(val & (1 << 7)) && s->txi->asserted)
sh_intc_toggle_source(s->txi, 0, -1);
}
if (!(val & (1 << 6)) && s->rxi->asserted) {
sh_intc_toggle_source(s->rxi, 0, -1);
}
return;
case 0x0c: /* FTDR / TDR */
if (s->chr) {
@ -117,12 +134,37 @@ static void sh_serial_ioport_write(void *opaque, uint32_t offs, uint32_t val)
s->flags &= ~SH_SERIAL_FLAG_RDF;
if (!(val & (1 << 0)))
s->flags &= ~SH_SERIAL_FLAG_DR;
if (!(val & (1 << 1)) || !(val & (1 << 0))) {
if (s->rxi && s->rxi->asserted) {
sh_intc_toggle_source(s->rxi, 0, -1);
}
}
return;
case 0x18: /* FCR */
s->fcr = val;
switch ((val >> 6) & 3) {
case 0:
s->rtrg = 1;
break;
case 1:
s->rtrg = 4;
break;
case 2:
s->rtrg = 8;
break;
case 3:
s->rtrg = 14;
break;
}
if (val & (1 << 1)) {
sh_serial_clear_fifo(s);
s->sr &= ~(1 << 1);
}
return;
case 0x20: /* SPTR */
s->sptr = val;
s->sptr = val & 0xf3;
return;
case 0x24: /* LSR */
return;
@ -190,9 +232,19 @@ static uint32_t sh_serial_ioport_read(void *opaque, uint32_t offs)
if (s->flags & SH_SERIAL_FLAG_DR)
ret |= (1 << 0);
if (s->scr & (1 << 5))
if (s->scr & (1 << 5))
s->flags |= SH_SERIAL_FLAG_TDE | SH_SERIAL_FLAG_TEND;
break;
case 0x14:
if (s->rx_cnt > 0) {
ret = s->rx_fifo[s->rx_tail++];
s->rx_cnt--;
if (s->rx_tail == SH_RX_FIFO_LENGTH)
s->rx_tail = 0;
if (s->rx_cnt < s->rtrg)
s->flags &= ~SH_SERIAL_FLAG_RDF;
}
break;
#if 0
case 0x18:
@ -219,6 +271,9 @@ static uint32_t sh_serial_ioport_read(void *opaque, uint32_t offs)
case 0x10:
ret = 0;
break;
case 0x14:
ret = s->rx_fifo[0];
break;
case 0x1c:
ret = s->sptr;
break;
@ -240,15 +295,33 @@ static uint32_t sh_serial_ioport_read(void *opaque, uint32_t offs)
static int sh_serial_can_receive(sh_serial_state *s)
{
return 0;
return s->scr & (1 << 4);
}
static void sh_serial_receive_byte(sh_serial_state *s, int ch)
{
if (s->feat & SH_SERIAL_FEAT_SCIF) {
if (s->rx_cnt < SH_RX_FIFO_LENGTH) {
s->rx_fifo[s->rx_head++] = ch;
if (s->rx_head == SH_RX_FIFO_LENGTH)
s->rx_head = 0;
s->rx_cnt++;
if (s->rx_cnt >= s->rtrg) {
s->flags |= SH_SERIAL_FLAG_RDF;
if (s->scr & (1 << 6) && s->rxi) {
sh_intc_toggle_source(s->rxi, 0, 1);
}
}
}
} else {
s->rx_fifo[0] = ch;
}
}
static void sh_serial_receive_break(sh_serial_state *s)
{
if (s->feat & SH_SERIAL_FEAT_SCIF)
s->sr |= (1 << 4);
}
static int sh_serial_can_receive1(void *opaque)
@ -313,6 +386,7 @@ void sh_serial_init (target_phys_addr_t base, int feat,
s->base = base;
s->feat = feat;
s->flags = SH_SERIAL_FLAG_TEND | SH_SERIAL_FLAG_TDE;
s->rtrg = 1;
s->smr = 0;
s->brr = 0xff;
@ -326,7 +400,7 @@ void sh_serial_init (target_phys_addr_t base, int feat,
s->dr = 0xff;
}
s->rx_cnt = 0;
sh_serial_clear_fifo(s);
s_io_memory = cpu_register_io_memory(0, sh_serial_readfn,
sh_serial_writefn, s);