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author | pbrook <pbrook@c046a42c-6fe2-441c-8c8c-71466251a162> | 2006-04-09 01:32:52 +0000 |
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committer | pbrook <pbrook@c046a42c-6fe2-441c-8c8c-71466251a162> | 2006-04-09 01:32:52 +0000 |
commit | cdbdb648b7c2867f0bb7dce27efb1986f770dedb (patch) | |
tree | f838b39e8f30e4872a792638e532d8ac8db6fbfc /hw/pl011.c | |
parent | 95219897ff4e6d0502b920c521fccc612ad913dd (diff) | |
download | qemu-cdbdb648b7c2867f0bb7dce27efb1986f770dedb.tar.gz qemu-cdbdb648b7c2867f0bb7dce27efb1986f770dedb.tar.bz2 qemu-cdbdb648b7c2867f0bb7dce27efb1986f770dedb.zip |
ARM Versatile Platform Baseboard emulation.
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@1804 c046a42c-6fe2-441c-8c8c-71466251a162
Diffstat (limited to 'hw/pl011.c')
-rw-r--r-- | hw/pl011.c | 251 |
1 files changed, 251 insertions, 0 deletions
diff --git a/hw/pl011.c b/hw/pl011.c new file mode 100644 index 0000000000..657f03bbe8 --- /dev/null +++ b/hw/pl011.c @@ -0,0 +1,251 @@ +/* + * Arm PrimeCell PL011 UART + * + * Copyright (c) 2006 CodeSourcery. + * Written by Paul Brook + * + * This code is licenced under the GPL. + */ + +#include "vl.h" + +typedef struct { + uint32_t base; + uint32_t readbuff; + uint32_t flags; + uint32_t lcr; + uint32_t cr; + uint32_t dmacr; + uint32_t int_enabled; + uint32_t int_level; + uint32_t read_fifo[16]; + uint32_t ilpr; + uint32_t ibrd; + uint32_t fbrd; + uint32_t ifl; + int read_pos; + int read_count; + int read_trigger; + CharDriverState *chr; + void *pic; + int irq; +} pl011_state; + +#define PL011_INT_TX 0x20 +#define PL011_INT_RX 0x10 + +#define PL011_FLAG_TXFE 0x80 +#define PL011_FLAG_RXFF 0x40 +#define PL011_FLAG_TXFF 0x20 +#define PL011_FLAG_RXFE 0x10 + +static const unsigned char pl011_id[] = +{ 0x11, 0x10, 0x14, 0x00, 0x0d, 0xf0, 0x05, 0xb1 }; + +static void pl011_update(pl011_state *s) +{ + uint32_t flags; + + flags = s->int_level & s->int_enabled; + pic_set_irq_new(s->pic, s->irq, flags != 0); +} + +static uint32_t pl011_read(void *opaque, target_phys_addr_t offset) +{ + pl011_state *s = (pl011_state *)opaque; + uint32_t c; + + offset -= s->base; + if (offset >= 0xfe0 && offset < 0x1000) { + return pl011_id[(offset - 0xfe0) >> 2]; + } + switch (offset >> 2) { + case 0: /* UARTDR */ + s->flags &= ~PL011_FLAG_RXFF; + c = s->read_fifo[s->read_pos]; + if (s->read_count > 0) { + s->read_count--; + if (++s->read_pos == 16) + s->read_pos = 0; + } + if (s->read_count == 0) { + s->flags |= PL011_FLAG_RXFE; + } + if (s->read_count == s->read_trigger - 1) + s->int_level &= ~ PL011_INT_RX; + pl011_update(s); + return c; + case 1: /* UARTCR */ + return 0; + case 6: /* UARTFR */ + return s->flags; + case 8: /* UARTILPR */ + return s->ilpr; + case 9: /* UARTIBRD */ + return s->ibrd; + case 10: /* UARTFBRD */ + return s->fbrd; + case 11: /* UARTLCR_H */ + return s->lcr; + case 12: /* UARTCR */ + return s->cr; + case 13: /* UARTIFLS */ + return s->ifl; + case 14: /* UARTIMSC */ + return s->int_enabled; + case 15: /* UARTRIS */ + return s->int_level; + case 16: /* UARTMIS */ + return s->int_level & s->int_enabled; + case 18: /* UARTDMACR */ + return s->dmacr; + default: + cpu_abort (cpu_single_env, "pl011_read: Bad offset %x\n", offset); + return 0; + } +} + +static void pl011_set_read_trigger(pl011_state *s) +{ +#if 0 + /* The docs say the RX interrupt is triggered when the FIFO exceeds + the threshold. However linux only reads the FIFO in response to an + interrupt. Triggering the interrupt when the FIFO is non-empty seems + to make things work. */ + if (s->lcr & 0x10) + s->read_trigger = (s->ifl >> 1) & 0x1c; + else +#endif + s->read_trigger = 1; +} + +static void pl011_write(void *opaque, target_phys_addr_t offset, + uint32_t value) +{ + pl011_state *s = (pl011_state *)opaque; + unsigned char ch; + + offset -= s->base; + switch (offset >> 2) { + case 0: /* UARTDR */ + /* ??? Check if transmitter is enabled. */ + ch = value; + if (s->chr) + qemu_chr_write(s->chr, &ch, 1); + s->int_level |= PL011_INT_TX; + pl011_update(s); + break; + case 1: /* UARTCR */ + s->cr = value; + break; + case 8: /* UARTUARTILPR */ + s->ilpr = value; + break; + case 9: /* UARTIBRD */ + s->ibrd = value; + break; + case 10: /* UARTFBRD */ + s->fbrd = value; + break; + case 11: /* UARTLCR_H */ + s->lcr = value; + pl011_set_read_trigger(s); + break; + case 12: /* UARTCR */ + /* ??? Need to implement the enable and loopback bits. */ + s->cr = value; + break; + case 13: /* UARTIFS */ + s->ifl = value; + pl011_set_read_trigger(s); + break; + case 14: /* UARTIMSC */ + s->int_enabled = value; + pl011_update(s); + break; + case 17: /* UARTICR */ + s->int_level &= ~value; + pl011_update(s); + break; + case 18: /* UARTDMACR */ + s->dmacr = value; + if (value & 3) + cpu_abort(cpu_single_env, "PL011: DMA not implemented\n"); + break; + default: + cpu_abort (cpu_single_env, "pl011_write: Bad offset %x\n", offset); + } +} + +static int pl011_can_recieve(void *opaque) +{ + pl011_state *s = (pl011_state *)opaque; + + if (s->lcr & 0x10) + return s->read_count < 16; + else + return s->read_count < 1; +} + +static void pl011_recieve(void *opaque, const uint8_t *buf, int size) +{ + pl011_state *s = (pl011_state *)opaque; + int slot; + + slot = s->read_pos + s->read_count; + if (slot >= 16) + slot -= 16; + s->read_fifo[slot] = *buf; + s->read_count++; + s->flags &= ~PL011_FLAG_RXFE; + if (s->cr & 0x10 || s->read_count == 16) { + s->flags |= PL011_FLAG_RXFF; + } + if (s->read_count == s->read_trigger) { + s->int_level |= PL011_INT_RX; + pl011_update(s); + } +} + +static void pl011_event(void *opaque, int event) +{ + /* ??? Should probably implement break. */ +} + +static CPUReadMemoryFunc *pl011_readfn[] = { + pl011_read, + pl011_read, + pl011_read +}; + +static CPUWriteMemoryFunc *pl011_writefn[] = { + pl011_write, + pl011_write, + pl011_write +}; + +void pl011_init(uint32_t base, void *pic, int irq, + CharDriverState *chr) +{ + int iomemtype; + pl011_state *s; + + s = (pl011_state *)qemu_mallocz(sizeof(pl011_state)); + iomemtype = cpu_register_io_memory(0, pl011_readfn, + pl011_writefn, s); + cpu_register_physical_memory(base, 0x00000fff, iomemtype); + s->base = base; + s->pic = pic; + s->irq = irq; + s->chr = chr; + s->read_trigger = 1; + s->ifl = 0x12; + s->cr = 0x300; + s->flags = 0x90; + if (chr){ + qemu_chr_add_read_handler(chr, pl011_can_recieve, pl011_recieve, s); + qemu_chr_add_event_handler(chr, pl011_event); + } + /* ??? Save/restore. */ +} + |