From 2938582fc6d75f019f08830a1e2f2e3ef0b40479 Mon Sep 17 00:00:00 2001 From: kettenis Date: Wed, 27 Jul 2022 20:18:46 +0000 Subject: [PATCH] Partially catch up with device tree bindings in mainline Linux. Initialize the burst size register such that DMA channels that haven't been initialized by Apple's bootloader also work. ok patrick@ --- sys/arch/arm64/dev/apldma.c | 64 +++++++++++++++++++++++++------------ 1 file changed, 44 insertions(+), 20 deletions(-) diff --git a/sys/arch/arm64/dev/apldma.c b/sys/arch/arm64/dev/apldma.c index a9a21d4be23..814d055f485 100644 --- a/sys/arch/arm64/dev/apldma.c +++ b/sys/arch/arm64/dev/apldma.c @@ -1,4 +1,4 @@ -/* $OpenBSD: apldma.c,v 1.1 2022/02/02 22:55:57 kettenis Exp $ */ +/* $OpenBSD: apldma.c,v 1.2 2022/07/27 20:18:46 kettenis Exp $ */ /* * Copyright (c) 2022 Mark Kettenis * @@ -38,36 +38,43 @@ * dropped as soon as official bindings are available. */ +/* + * The device tree bindings for this hardware use separate Tx and Rx + * channels with Tx channels using even channel numbers and Rx + * channels using odd channel numbers. + */ + #define DMA_TX_EN 0x0000 #define DMA_TX_EN_CLR 0x0004 #define DMA_TX_INTR 0x0034 -#define DMA_TX_CTL(chan) (0x8000 + (chan) * 0x400) +#define DMA_TX_CTL(chan) (0x8000 + ((chan) / 2) * 0x400) #define DMA_TX_CTL_RESET_RINGS (1 << 0) -#define DMA_TX_INTRSTAT(chan) (0x8014 + (chan) * 0x400) +#define DMA_TX_INTRSTAT(chan) (0x8014 + ((chan) / 2) * 0x400) #define DMA_TX_INTRSTAT_DESC_DONE (1 << 0) #define DMA_TX_INTRSTAT_ERR (1 << 6) -#define DMA_TX_INTRMASK(chan) (0x8024 + (chan) * 0x400) +#define DMA_TX_INTRMASK(chan) (0x8024 + ((chan) / 2) * 0x400) #define DMA_TX_INTRMASK_DESC_DONE (1 << 0) #define DMA_TX_INTRMASK_ERR (1 << 6) -#define DMA_TX_BUS_WIDTH(chan) (0x8040 + (chan) * 0x400) +#define DMA_TX_BUS_WIDTH(chan) (0x8040 + ((chan) / 2) * 0x400) #define DMA_TX_BUS_WIDTH_8BIT (0 << 0) #define DMA_TX_BUS_WIDTH_16BIT (1 << 0) #define DMA_TX_BUS_WIDTH_32BIT (2 << 0) #define DMA_TX_BUS_WIDTH_FRAME_2_WORDS (1 << 4) #define DMA_TX_BUS_WIDTH_FRAME_4_WORDS (2 << 4) -#define DMA_TX_BURST_SIZE(chan) (0x8054 + (chan) * 0x400) -#define DMA_TX_RESIDUE(chan) (0x8064 + (chan) * 0x400) -#define DMA_TX_DESC_RING(chan) (0x8070 + (chan) * 0x400) +#define DMA_TX_BURST_SIZE(chan) (0x8054 + ((chan) / 2) * 0x400) +#define DMA_TX_BURST_SIZE_MAGIC 0x00c00060 +#define DMA_TX_RESIDUE(chan) (0x8064 + ((chan) / 2) * 0x400) +#define DMA_TX_DESC_RING(chan) (0x8070 + ((chan) / 2) * 0x400) #define DMA_TX_DESC_RING_FULL (1 << 9) -#define DMA_TX_REPORT_RING(chan) (0x8074 + (chan) * 0x400) +#define DMA_TX_REPORT_RING(chan) (0x8074 + ((chan) / 2) * 0x400) #define DMA_TX_REPORT_RING_EMPTY (1 << 8) -#define DMA_TX_DESC_WRITE(chan) (0x10000 + (chan) * 4) -#define DMA_TX_REPORT_READ(chan) (0x10100 + (chan) * 4) +#define DMA_TX_DESC_WRITE(chan) (0x10000 + ((chan) / 2) * 4) +#define DMA_TX_REPORT_READ(chan) (0x10100 + ((chan) / 2) * 4) #define DMA_DESC_NOTIFY (1 << 16) #define DMA_NUM_DESCRIPTORS 4 -#define DMA_NUM_CHANNELS 4 +#define DMA_NUM_INTERRUPTS 4 #define HREAD4(sc, reg) \ (bus_space_read_4((sc)->sc_iot, (sc)->sc_ioh, (reg))) @@ -101,7 +108,8 @@ struct apldma_softc { int sc_node; void *sc_ih; - struct apldma_channel *sc_ac[DMA_NUM_CHANNELS]; + int sc_nchannels; + struct apldma_channel **sc_ac; }; struct apldma_softc *apldma_sc; @@ -145,6 +153,14 @@ apldma_attach(struct device *parent, struct device *self, void *aux) return; } + sc->sc_nchannels = OF_getpropint(faa->fa_node, "dma-channels", 0); + if (sc->sc_nchannels == 0) { + printf(": no DMA channels\n"); + goto unmap; + } + sc->sc_ac = mallocarray(sc->sc_nchannels, + sizeof(struct apldma_channel), M_DEVBUF, M_WAITOK | M_ZERO); + sc->sc_dmat = faa->fa_dmat; sc->sc_node = faa->fa_node; @@ -154,7 +170,7 @@ apldma_attach(struct device *parent, struct device *self, void *aux) apldma_intr, sc, sc->sc_dev.dv_xname); if (sc->sc_ih == NULL) { printf(": can't establish interrupt\n"); - goto unmap; + goto free; } printf("\n"); @@ -162,6 +178,9 @@ apldma_attach(struct device *parent, struct device *self, void *aux) apldma_sc = sc; return; +free: + free(sc->sc_ac, M_DEVBUF, + sc->sc_nchannels * sizeof(struct apldma_channel)); unmap: bus_space_unmap(sc->sc_iot, sc->sc_ioh, faa->fa_reg[0].size); } @@ -199,8 +218,8 @@ apldma_intr(void *arg) unsigned int chan, i; intr = HREAD4(sc, DMA_TX_INTR); - for (chan = 0; chan < DMA_NUM_CHANNELS; chan++) { - if ((intr & (1 << chan)) == 0) + for (chan = 0; chan < sc->sc_nchannels; chan += 2) { + if ((intr & (1 << (chan / 2))) == 0) continue; intrstat = HREAD4(sc, DMA_TX_INTRSTAT(chan)); @@ -208,7 +227,7 @@ apldma_intr(void *arg) if ((intrstat & DMA_TX_INTRSTAT_DESC_DONE) == 0) continue; - + for (i = 0; i < DMA_NUM_DESCRIPTORS; i++) { uint32_t status; @@ -240,7 +259,11 @@ apldma_alloc_channel(unsigned int chan) struct apldma_softc *sc = apldma_sc; struct apldma_channel *ac; - if (chan >= DMA_NUM_CHANNELS) + if (chan >= sc->sc_nchannels) + return NULL; + + /* We only support Tx channels for now. */ + if ((chan % 2) != 0) return NULL; ac = malloc(sizeof(*ac), M_DEVBUF, M_WAITOK); @@ -337,6 +360,7 @@ apldma_trigger_output(struct apldma_channel *ac, void *start, void *end, default: return EINVAL; } + HWRITE4(sc, DMA_TX_BURST_SIZE(ac->ac_chan), DMA_TX_BURST_SIZE_MAGIC); /* Reset rings. */ HWRITE4(sc, DMA_TX_CTL(ac->ac_chan), DMA_TX_CTL_RESET_RINGS); @@ -351,7 +375,7 @@ apldma_trigger_output(struct apldma_channel *ac, void *start, void *end, apldma_fill_descriptors(ac); /* Start DMA transfer. */ - HWRITE4(sc, DMA_TX_EN, 1 << ac->ac_chan); + HWRITE4(sc, DMA_TX_EN, 1 << (ac->ac_chan / 2)); return 0; } @@ -362,7 +386,7 @@ apldma_halt_output(struct apldma_channel *ac) struct apldma_softc *sc = ac->ac_sc; /* Stop DMA transfer. */ - HWRITE4(sc, DMA_TX_EN_CLR, 1 << ac->ac_chan); + HWRITE4(sc, DMA_TX_EN_CLR, 1 << (ac->ac_chan / 2)); /* Mask all interrupts. */ HWRITE4(sc, DMA_TX_INTRMASK(ac->ac_chan), 0); -- 2.20.1