diff options
author | pbrook <pbrook@c046a42c-6fe2-441c-8c8c-71466251a162> | 2007-11-11 00:04:49 +0000 |
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committer | pbrook <pbrook@c046a42c-6fe2-441c-8c8c-71466251a162> | 2007-11-11 00:04:49 +0000 |
commit | 9ee6e8bb853bdea7ef6c645a1a07aa55fd206aba (patch) | |
tree | 1cd430d3d9ac641c8550cfd8956dbcce1a4b9121 /hw/pl022.c | |
parent | ee4e83ed8ddc8dac572a0123398adf78b63014ae (diff) |
ARMv7 support.
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@3572 c046a42c-6fe2-441c-8c8c-71466251a162
Diffstat (limited to 'hw/pl022.c')
-rw-r--r-- | hw/pl022.c | 264 |
1 files changed, 264 insertions, 0 deletions
diff --git a/hw/pl022.c b/hw/pl022.c new file mode 100644 index 0000000000..d7c735b7ce --- /dev/null +++ b/hw/pl022.c @@ -0,0 +1,264 @@ +/* + * Arm PrimeCell PL022 Synchronous Serial Port + * + * Copyright (c) 2007 CodeSourcery. + * Written by Paul Brook + * + * This code is licenced under the GPL. + */ + +#include "vl.h" + +//#define DEBUG_PL022 1 + +#ifdef DEBUG_PL022 +#define DPRINTF(fmt, args...) \ +do { printf("pl022: " fmt , ##args); } while (0) +#define BADF(fmt, args...) \ +do { fprintf(stderr, "pl022: error: " fmt , ##args); exit(1);} while (0) +#else +#define DPRINTF(fmt, args...) do {} while(0) +#define BADF(fmt, args...) \ +do { fprintf(stderr, "pl022: error: " fmt , ##args);} while (0) +#endif + +#define PL022_CR1_LBM 0x01 +#define PL022_CR1_SSE 0x02 +#define PL022_CR1_MS 0x04 +#define PL022_CR1_SDO 0x08 + +#define PL022_SR_TFE 0x01 +#define PL022_SR_TNF 0x02 +#define PL022_SR_RNE 0x04 +#define PL022_SR_RFF 0x08 +#define PL022_SR_BSY 0x10 + +#define PL022_INT_ROR 0x01 +#define PL022_INT_RT 0x04 +#define PL022_INT_RX 0x04 +#define PL022_INT_TX 0x08 + +typedef struct { + uint32_t base; + uint32_t cr0; + uint32_t cr1; + uint32_t bitmask; + uint32_t sr; + uint32_t cpsr; + uint32_t is; + uint32_t im; + /* The FIFO head points to the next empty entry. */ + int tx_fifo_head; + int rx_fifo_head; + int tx_fifo_len; + int rx_fifo_len; + uint16_t tx_fifo[8]; + uint16_t rx_fifo[8]; + qemu_irq irq; + int (*xfer_cb)(void *, int); + void *opaque; +} pl022_state; + +static const unsigned char pl022_id[8] = + { 0x22, 0x10, 0x04, 0x00, 0x0d, 0xf0, 0x05, 0xb1 }; + +static void pl022_update(pl022_state *s) +{ + s->sr = 0; + if (s->tx_fifo_len == 0) + s->sr |= PL022_SR_TFE; + if (s->tx_fifo_len != 8) + s->sr |= PL022_SR_TNF; + if (s->rx_fifo_len != 0) + s->sr |= PL022_SR_RNE; + if (s->rx_fifo_len == 8) + s->sr |= PL022_SR_RFF; + if (s->tx_fifo_len) + s->sr |= PL022_SR_BSY; + s->is = 0; + if (s->rx_fifo_len >= 4) + s->is |= PL022_INT_RX; + if (s->tx_fifo_len <= 4) + s->is |= PL022_INT_TX; + + qemu_set_irq(s->irq, (s->is & s->im) != 0); +} + +static void pl022_xfer(pl022_state *s) +{ + int i; + int o; + int val; + + if ((s->cr1 & PL022_CR1_SSE) == 0) { + pl022_update(s); + DPRINTF("Disabled\n"); + return; + } + + DPRINTF("Maybe xfer %d/%d\n", s->tx_fifo_len, s->rx_fifo_len); + i = (s->tx_fifo_head - s->tx_fifo_len) & 7; + o = s->rx_fifo_head; + /* ??? We do not emulate the line speed. + This may break some applications. The are two problematic cases: + (a) A driver feeds data into the TX FIFO until it is full, + and only then drains the RX FIFO. On real hardware the CPU can + feed data fast enough that the RX fifo never gets chance to overflow. + (b) A driver transmits data, deliberately allowing the RX FIFO to + overflow because it ignores the RX data anyway. + + We choose to support (a) by stalling the transmit engine if it would + cause the RX FIFO to overflow. In practice much transmit-only code + falls into (a) because it flushes the RX FIFO to determine when + the transfer has completed. */ + while (s->tx_fifo_len && s->rx_fifo_len < 8) { + DPRINTF("xfer\n"); + val = s->tx_fifo[i]; + if (s->cr1 & PL022_CR1_LBM) { + /* Loopback mode. */ + } else if (s->xfer_cb) { + val = s->xfer_cb(s->opaque, val); + } else { + val = 0; + } + s->rx_fifo[o] = val & s->bitmask; + i = (i + 1) & 7; + o = (o + 1) & 7; + s->tx_fifo_len--; + s->rx_fifo_len++; + } + s->rx_fifo_head = o; + pl022_update(s); +} + +static uint32_t pl022_read(void *opaque, target_phys_addr_t offset) +{ + pl022_state *s = (pl022_state *)opaque; + int val; + + offset -= s->base; + if (offset >= 0xfe0 && offset < 0x1000) { + return pl022_id[(offset - 0xfe0) >> 2]; + } + switch (offset) { + case 0x00: /* CR0 */ + return s->cr0; + case 0x04: /* CR1 */ + return s->cr1; + case 0x08: /* DR */ + if (s->rx_fifo_len) { + val = s->rx_fifo[(s->rx_fifo_head - s->rx_fifo_len) & 7]; + DPRINTF("RX %02x\n", val); + s->rx_fifo_len--; + pl022_xfer(s); + } else { + val = 0; + } + return val; + case 0x0c: /* SR */ + return s->sr; + case 0x10: /* CPSR */ + return s->cpsr; + case 0x14: /* IMSC */ + return s->im; + case 0x18: /* RIS */ + return s->is; + case 0x1c: /* MIS */ + return s->im & s->is; + case 0x20: /* DMACR */ + /* Not implemented. */ + return 0; + default: + cpu_abort (cpu_single_env, "pl022_read: Bad offset %x\n", + (int)offset); + return 0; + } +} + +static void pl022_write(void *opaque, target_phys_addr_t offset, + uint32_t value) +{ + pl022_state *s = (pl022_state *)opaque; + + offset -= s->base; + switch (offset) { + case 0x00: /* CR0 */ + s->cr0 = value; + /* Clock rate and format are ignored. */ + s->bitmask = (1 << ((value & 15) + 1)) - 1; + break; + case 0x04: /* CR1 */ + s->cr1 = value; + if ((s->cr1 & (PL022_CR1_MS | PL022_CR1_SSE)) + == (PL022_CR1_MS | PL022_CR1_SSE)) { + BADF("SPI slave mode not implemented\n"); + } + pl022_xfer(s); + break; + case 0x08: /* DR */ + if (s->tx_fifo_len < 8) { + DPRINTF("TX %02x\n", value); + s->tx_fifo[s->tx_fifo_head] = value & s->bitmask; + s->tx_fifo_head = (s->tx_fifo_head + 1) & 7; + s->tx_fifo_len++; + pl022_xfer(s); + } + break; + case 0x10: /* CPSR */ + /* Prescaler. Ignored. */ + s->cpsr = value & 0xff; + break; + case 0x14: /* IMSC */ + s->im = value; + pl022_update(s); + break; + case 0x20: /* DMACR */ + if (value) + cpu_abort (cpu_single_env, "pl022: DMA not implemented\n"); + break; + default: + cpu_abort (cpu_single_env, "pl022_write: Bad offset %x\n", + (int)offset); + } +} + +static void pl022_reset(pl022_state *s) +{ + s->rx_fifo_len = 0; + s->tx_fifo_len = 0; + s->im = 0; + s->is = PL022_INT_TX; + s->sr = PL022_SR_TFE | PL022_SR_TNF; +} + +static CPUReadMemoryFunc *pl022_readfn[] = { + pl022_read, + pl022_read, + pl022_read +}; + +static CPUWriteMemoryFunc *pl022_writefn[] = { + pl022_write, + pl022_write, + pl022_write +}; + +void pl022_init(uint32_t base, qemu_irq irq, int (*xfer_cb)(void *, int), + void * opaque) +{ + int iomemtype; + pl022_state *s; + + s = (pl022_state *)qemu_mallocz(sizeof(pl022_state)); + iomemtype = cpu_register_io_memory(0, pl022_readfn, + pl022_writefn, s); + cpu_register_physical_memory(base, 0x00001000, iomemtype); + s->base = base; + s->irq = irq; + s->xfer_cb = xfer_cb; + s->opaque = opaque; + pl022_reset(s); + /* ??? Save/restore. */ +} + + |