?? pxa2xx_dma.c
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/* * Intel XScale PXA255/270 DMA controller. * * Copyright (c) 2006 Openedhand Ltd. * Copyright (c) 2006 Thorsten Zitterell * Written by Andrzej Zaborowski <balrog@zabor.org> * * This code is licenced under the GPL. */#include "hw.h"#include "pxa.h"struct pxa2xx_dma_channel_s { target_phys_addr_t descr; target_phys_addr_t src; target_phys_addr_t dest; uint32_t cmd; uint32_t state; int request;};/* Allow the DMA to be used as a PIC. */typedef void (*pxa2xx_dma_handler_t)(void *opaque, int irq, int level);struct pxa2xx_dma_state_s { pxa2xx_dma_handler_t handler; target_phys_addr_t base; qemu_irq irq; uint32_t stopintr; uint32_t eorintr; uint32_t rasintr; uint32_t startintr; uint32_t endintr; uint32_t align; uint32_t pio; int channels; struct pxa2xx_dma_channel_s *chan; uint8_t *req; /* Flag to avoid recursive DMA invocations. */ int running;};#define PXA255_DMA_NUM_CHANNELS 16#define PXA27X_DMA_NUM_CHANNELS 32#define PXA2XX_DMA_NUM_REQUESTS 75#define DCSR0 0x0000 /* DMA Control / Status register for Channel 0 */#define DCSR31 0x007c /* DMA Control / Status register for Channel 31 */#define DALGN 0x00a0 /* DMA Alignment register */#define DPCSR 0x00a4 /* DMA Programmed I/O Control Status register */#define DRQSR0 0x00e0 /* DMA DREQ<0> Status register */#define DRQSR1 0x00e4 /* DMA DREQ<1> Status register */#define DRQSR2 0x00e8 /* DMA DREQ<2> Status register */#define DINT 0x00f0 /* DMA Interrupt register */#define DRCMR0 0x0100 /* Request to Channel Map register 0 */#define DRCMR63 0x01fc /* Request to Channel Map register 63 */#define D_CH0 0x0200 /* Channel 0 Descriptor start */#define DRCMR64 0x1100 /* Request to Channel Map register 64 */#define DRCMR74 0x1128 /* Request to Channel Map register 74 *//* Per-channel register */#define DDADR 0x00#define DSADR 0x01#define DTADR 0x02#define DCMD 0x03/* Bit-field masks */#define DRCMR_CHLNUM 0x1f#define DRCMR_MAPVLD (1 << 7)#define DDADR_STOP (1 << 0)#define DDADR_BREN (1 << 1)#define DCMD_LEN 0x1fff#define DCMD_WIDTH(x) (1 << ((((x) >> 14) & 3) - 1))#define DCMD_SIZE(x) (4 << (((x) >> 16) & 3))#define DCMD_FLYBYT (1 << 19)#define DCMD_FLYBYS (1 << 20)#define DCMD_ENDIRQEN (1 << 21)#define DCMD_STARTIRQEN (1 << 22)#define DCMD_CMPEN (1 << 25)#define DCMD_FLOWTRG (1 << 28)#define DCMD_FLOWSRC (1 << 29)#define DCMD_INCTRGADDR (1 << 30)#define DCMD_INCSRCADDR (1 << 31)#define DCSR_BUSERRINTR (1 << 0)#define DCSR_STARTINTR (1 << 1)#define DCSR_ENDINTR (1 << 2)#define DCSR_STOPINTR (1 << 3)#define DCSR_RASINTR (1 << 4)#define DCSR_REQPEND (1 << 8)#define DCSR_EORINT (1 << 9)#define DCSR_CMPST (1 << 10)#define DCSR_MASKRUN (1 << 22)#define DCSR_RASIRQEN (1 << 23)#define DCSR_CLRCMPST (1 << 24)#define DCSR_EORSTOPEN (1 << 26)#define DCSR_EORJMPEN (1 << 27)#define DCSR_EORIRQEN (1 << 28)#define DCSR_STOPIRQEN (1 << 29)#define DCSR_NODESCFETCH (1 << 30)#define DCSR_RUN (1 << 31)static inline void pxa2xx_dma_update(struct pxa2xx_dma_state_s *s, int ch){ if (ch >= 0) { if ((s->chan[ch].state & DCSR_STOPIRQEN) && (s->chan[ch].state & DCSR_STOPINTR)) s->stopintr |= 1 << ch; else s->stopintr &= ~(1 << ch); if ((s->chan[ch].state & DCSR_EORIRQEN) && (s->chan[ch].state & DCSR_EORINT)) s->eorintr |= 1 << ch; else s->eorintr &= ~(1 << ch); if ((s->chan[ch].state & DCSR_RASIRQEN) && (s->chan[ch].state & DCSR_RASINTR)) s->rasintr |= 1 << ch; else s->rasintr &= ~(1 << ch); if (s->chan[ch].state & DCSR_STARTINTR) s->startintr |= 1 << ch; else s->startintr &= ~(1 << ch); if (s->chan[ch].state & DCSR_ENDINTR) s->endintr |= 1 << ch; else s->endintr &= ~(1 << ch); } if (s->stopintr | s->eorintr | s->rasintr | s->startintr | s->endintr) qemu_irq_raise(s->irq); else qemu_irq_lower(s->irq);}static inline void pxa2xx_dma_descriptor_fetch( struct pxa2xx_dma_state_s *s, int ch){ uint32_t desc[4]; target_phys_addr_t daddr = s->chan[ch].descr & ~0xf; if ((s->chan[ch].descr & DDADR_BREN) && (s->chan[ch].state & DCSR_CMPST)) daddr += 32; cpu_physical_memory_read(daddr, (uint8_t *) desc, 16); s->chan[ch].descr = desc[DDADR]; s->chan[ch].src = desc[DSADR]; s->chan[ch].dest = desc[DTADR]; s->chan[ch].cmd = desc[DCMD]; if (s->chan[ch].cmd & DCMD_FLOWSRC) s->chan[ch].src &= ~3; if (s->chan[ch].cmd & DCMD_FLOWTRG) s->chan[ch].dest &= ~3; if (s->chan[ch].cmd & (DCMD_CMPEN | DCMD_FLYBYS | DCMD_FLYBYT)) printf("%s: unsupported mode in channel %i\n", __FUNCTION__, ch); if (s->chan[ch].cmd & DCMD_STARTIRQEN) s->chan[ch].state |= DCSR_STARTINTR;}static void pxa2xx_dma_run(struct pxa2xx_dma_state_s *s){ int c, srcinc, destinc; uint32_t n, size; uint32_t width; uint32_t length; char buffer[32]; struct pxa2xx_dma_channel_s *ch; if (s->running ++) return; while (s->running) { s->running = 1; for (c = 0; c < s->channels; c ++) { ch = &s->chan[c]; while ((ch->state & DCSR_RUN) && !(ch->state & DCSR_STOPINTR)) { /* Test for pending requests */ if ((ch->cmd & (DCMD_FLOWSRC | DCMD_FLOWTRG)) && !ch->request) break; length = ch->cmd & DCMD_LEN; size = DCMD_SIZE(ch->cmd); width = DCMD_WIDTH(ch->cmd); srcinc = (ch->cmd & DCMD_INCSRCADDR) ? width : 0; destinc = (ch->cmd & DCMD_INCTRGADDR) ? width : 0; while (length) { size = MIN(length, size); for (n = 0; n < size; n += width) { ch->src += srcinc; } for (n = 0; n < size; n += width) { cpu_physical_memory_write(ch->dest, buffer + n, width); ch->dest += destinc; } length -= size; if ((ch->cmd & (DCMD_FLOWSRC | DCMD_FLOWTRG)) && !ch->request) { ch->state |= DCSR_EORINT; if (ch->state & DCSR_EORSTOPEN) ch->state |= DCSR_STOPINTR; if ((ch->state & DCSR_EORJMPEN) && !(ch->state & DCSR_NODESCFETCH)) pxa2xx_dma_descriptor_fetch(s, c); break; } } ch->cmd = (ch->cmd & ~DCMD_LEN) | length; /* Is the transfer complete now? */ if (!length) { if (ch->cmd & DCMD_ENDIRQEN) ch->state |= DCSR_ENDINTR; if ((ch->state & DCSR_NODESCFETCH) || (ch->descr & DDADR_STOP) || (ch->state & DCSR_EORSTOPEN)) { ch->state |= DCSR_STOPINTR; ch->state &= ~DCSR_RUN; break; } ch->state |= DCSR_STOPINTR; break; } } } s->running --; }}static uint32_t pxa2xx_dma_read(void *opaque, target_phys_addr_t offset){ struct pxa2xx_dma_state_s *s = (struct pxa2xx_dma_state_s *) opaque; unsigned int channel; offset -= s->base; switch (offset) { case DRCMR64 ... DRCMR74: offset -= DRCMR64 - DRCMR0 - (64 << 2); /* Fall through */ case DRCMR0 ... DRCMR63: channel = (offset - DRCMR0) >> 2; return s->req[channel]; case DRQSR0: case DRQSR1: case DRQSR2: return 0; case DCSR0 ... DCSR31: channel = offset >> 2; if (s->chan[channel].request) return s->chan[channel].state | DCSR_REQPEND; return s->chan[channel].state;
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