On 28-08-23, 19:00, Martin Povišer wrote: > Add a dmaengine driver for the Apple SIO coprocessor found on Apple > SoCs where it provides DMA services. Have the driver support cyclic > transactions so that ALSA drivers can rely on it in audio output to > HDMI and DisplayPort. > > Signed-off-by: Martin Povišer <povik+lin@xxxxxxxxxxx> > --- > MAINTAINERS | 2 + > drivers/dma/Kconfig | 11 + > drivers/dma/Makefile | 1 + > drivers/dma/apple-sio.c | 868 ++++++++++++++++++++++++++++++++++++++++ > 4 files changed, 882 insertions(+) > create mode 100644 drivers/dma/apple-sio.c > > diff --git a/MAINTAINERS b/MAINTAINERS > index 3be1bdfe8ecc..e65cf3d535ef 100644 > --- a/MAINTAINERS > +++ b/MAINTAINERS > @@ -1865,7 +1865,9 @@ M: Martin Povišer <povik+lin@xxxxxxxxxxx> > L: asahi@xxxxxxxxxxxxxxx > L: alsa-devel@xxxxxxxxxxxxxxxx (moderated for non-subscribers) > S: Maintained > +F: Documentation/devicetree/bindings/dma/apple,sio.yaml > F: Documentation/devicetree/bindings/sound/apple,* > +F: drivers/dma/apple-sio.c > F: sound/soc/apple/* > F: sound/soc/codecs/cs42l83-i2c.c > > diff --git a/drivers/dma/Kconfig b/drivers/dma/Kconfig > index f52d36e713f3..6e385dee2d3d 100644 > --- a/drivers/dma/Kconfig > +++ b/drivers/dma/Kconfig > @@ -89,10 +89,21 @@ config APPLE_ADMAC > tristate "Apple ADMAC support" > depends on ARCH_APPLE || COMPILE_TEST > select DMA_ENGINE > + select DMA_VIRTUAL_CHANNELS > default ARCH_APPLE > help > Enable support for Audio DMA Controller found on Apple Silicon SoCs. > > +config APPLE_SIO > + tristate "Apple SIO support" > + depends on ARCH_APPLE || COMPILE_TEST > + depends on APPLE_RTKIT > + select DMA_ENGINE > + default ARCH_APPLE > + help > + Enable support for the SIO coprocessor found on Apple Silicon SoCs > + where it provides DMA services. > + > config AT_HDMAC > tristate "Atmel AHB DMA support" > depends on ARCH_AT91 > diff --git a/drivers/dma/Makefile b/drivers/dma/Makefile > index 83553a97a010..787583ff2d45 100644 > --- a/drivers/dma/Makefile > +++ b/drivers/dma/Makefile > @@ -18,6 +18,7 @@ obj-$(CONFIG_AMBA_PL08X) += amba-pl08x.o > obj-$(CONFIG_AMCC_PPC440SPE_ADMA) += ppc4xx/ > obj-$(CONFIG_AMD_PTDMA) += ptdma/ > obj-$(CONFIG_APPLE_ADMAC) += apple-admac.o > +obj-$(CONFIG_APPLE_SIO) += apple-sio.o > obj-$(CONFIG_AT_HDMAC) += at_hdmac.o > obj-$(CONFIG_AT_XDMAC) += at_xdmac.o > obj-$(CONFIG_AXI_DMAC) += dma-axi-dmac.o > diff --git a/drivers/dma/apple-sio.c b/drivers/dma/apple-sio.c > new file mode 100644 > index 000000000000..e15deeded4dc > --- /dev/null > +++ b/drivers/dma/apple-sio.c > @@ -0,0 +1,868 @@ > +// SPDX-License-Identifier: GPL-2.0-only OR MIT > +/* > + * Driver for SIO coprocessor on t8103 (M1) and other Apple SoCs > + * > + * Copyright (C) The Asahi Linux Contributors > + */ > + > +#include <linux/bitfield.h> > +#include <linux/bits.h> > +#include <linux/completion.h> > +#include <linux/device.h> > +#include <linux/dma-mapping.h> > +#include <linux/init.h> > +#include <linux/interrupt.h> > +#include <linux/module.h> > +#include <linux/of_device.h> > +#include <linux/of_dma.h> > +#include <linux/soc/apple/rtkit.h> > + > +#include "dmaengine.h" > +#include "virt-dma.h" > + > +#define NCHANNELS_MAX 0x80 > + > +#define REG_CPU_CONTROL 0x44 > +#define CPU_CONTROL_RUN BIT(4) > + > +#define SIOMSG_DATA GENMASK(63, 32) > +#define SIOMSG_TYPE GENMASK(23, 16) > +#define SIOMSG_PARAM GENMASK(31, 24) > +#define SIOMSG_TAG GENMASK(13, 8) > +#define SIOMSG_EP GENMASK(7, 0) > + > +#define EP_SIO 0x20 > + > +#define MSG_START 0x2 > +#define MSG_SETUP 0x3 > +#define MSG_CONFIGURE 0x5 > +#define MSG_ISSUE 0x6 > +#define MSG_TERMINATE 0x8 > +#define MSG_ACK 0x65 > +#define MSG_NACK 0x66 > +#define MSG_STARTED 0x67 > +#define MSG_REPORT 0x68 > + > +#define SIO_CALL_TIMEOUT_MS 100 > +#define SIO_SHMEM_SIZE 0x1000 > +#define SIO_NO_DESC_SLOTS 64 > + > +/* > + * There are two kinds of 'transaction descriptors' in play here. > + * > + * There's the struct sio_tx, and the struct dma_async_tx_descriptor embedded > + * inside, which jointly represent a transaction to the dmaengine subsystem. > + * At this time we only support those transactions to be cyclic. > + * > + * Then there are the coprocessor descriptors, which is what the coprocessor > + * knows and understands. These don't seem to have a cyclic regime, so we can't > + * map the dmaengine transaction on an exact coprocessor counterpart. Instead > + * we continually queue up many coprocessor descriptors to implement a cyclic > + * transaction. > + * > + * The number below is the maximum of how far ahead (how many) coprocessor > + * descriptors we should be queuing up, per channel, for a cyclic transaction. > + * Basically it's a made-up number. > + */ > +#define SIO_MAX_NINFLIGHT 4 you meant SIO_MAX_INFLIGHT if not what is NINFLIGHT? > +struct sio_coproc_desc { > + u32 pad1; > + u32 flag; > + u64 unk; > + u64 iova; > + u64 size; > + u64 pad2; > + u64 pad3; > +} __packed; > +static_assert(sizeof(struct sio_coproc_desc) == 48); > + > +struct sio_shmem_chan_config { > + u32 datashape; > + u32 timeout; > + u32 fifo; > + u32 threshold; > + u32 limit; > +} __packed; > + > +struct sio_data; > +struct sio_tx; > + > +struct sio_chan { > + unsigned int no; > + struct sio_data *host; > + struct virt_dma_chan vc; > + struct work_struct terminate_wq; > + > + struct sio_tx *current_tx; > +}; > + > +#define SIO_NTAGS 16 > + > +typedef void (*sio_ack_callback)(struct sio_chan *, void *, bool); what is this callback used for? > + > +struct sio_data { > + void __iomem *base; > + struct dma_device dma; > + struct device *dev; > + struct apple_rtkit *rtk; > + void *shmem; > + struct sio_coproc_desc *shmem_desc_base; > + unsigned long *desc_allocated; > + > + struct sio_tagdata { > + DECLARE_BITMAP(allocated, SIO_NTAGS); > + int last_tag; > + > + struct completion completions[SIO_NTAGS]; > + bool atomic[SIO_NTAGS]; > + bool acked[SIO_NTAGS]; > + > + sio_ack_callback ack_callback[SIO_NTAGS]; > + void *cookie[SIO_NTAGS]; > + } tags; > + > + int nchannels; > + struct sio_chan channels[]; > +}; > + > +struct sio_tx { > + struct virt_dma_desc vd; > + struct completion done; > + > + bool terminated; > + size_t period_len; > + int nperiods; > + int ninflight; > + int next; > + > + struct sio_coproc_desc *siodesc[]; > +}; > + > +static int sio_send_siomsg(struct sio_data *sio, u64 msg); > +static int sio_send_siomsg_atomic(struct sio_data *sio, u64 msg, > + sio_ack_callback ack_callback, > + void *cookie); > +static int sio_call(struct sio_data *sio, u64 msg); > + > +static struct sio_chan *to_sio_chan(struct dma_chan *chan) > +{ > + return container_of(chan, struct sio_chan, vc.chan); > +} > + > +static struct sio_tx *to_sio_tx(struct dma_async_tx_descriptor *tx) > +{ > + return container_of(tx, struct sio_tx, vd.tx); > +} > + > +static int sio_alloc_tag(struct sio_data *sio) > +{ > + struct sio_tagdata *tags = &sio->tags; > + int tag, i; > + > + /* > + * Because tag number 0 is special, the usable tag range > + * is 1...(SIO_NTAGS - 1). So, to pick the next usable tag, > + * we do modulo (SIO_NTAGS - 1) *then* plus one. > + */ > + > +#define SIO_USABLE_TAGS (SIO_NTAGS - 1) > + tag = (READ_ONCE(tags->last_tag) % SIO_USABLE_TAGS) + 1; > + > + for (i = 0; i < SIO_USABLE_TAGS; i++) { > + if (!test_and_set_bit(tag, tags->allocated)) > + break; > + > + tag = (tag % SIO_USABLE_TAGS) + 1; > + } > + > + WRITE_ONCE(tags->last_tag, tag); > + > + if (i < SIO_USABLE_TAGS) > + return tag; > + else > + return -EBUSY; > +#undef SIO_USABLE_TAGS ida_alloc can be used as well to get a tag as well > +} > + > +static void sio_free_tag(struct sio_data *sio, int tag) > +{ > + struct sio_tagdata *tags = &sio->tags; > + > + if (WARN_ON(tag >= SIO_NTAGS)) > + return; > + > + tags->atomic[tag] = false; > + tags->ack_callback[tag] = NULL; > + > + WARN_ON(!test_and_clear_bit(tag, tags->allocated)); > +} > + > +static void sio_set_tag_atomic(struct sio_data *sio, int tag, > + sio_ack_callback ack_callback, > + void *cookie) > +{ > + struct sio_tagdata *tags = &sio->tags; > + > + tags->atomic[tag] = true; > + tags->ack_callback[tag] = ack_callback; > + tags->cookie[tag] = cookie; > +} > + > +static struct sio_coproc_desc *sio_alloc_desc(struct sio_data *sio) > +{ > + int i; > + > + for (i = 0; i < SIO_NO_DESC_SLOTS; i++) > + if (!test_and_set_bit(i, sio->desc_allocated)) > + return sio->shmem_desc_base + i; > + > + return NULL; > +} > + > +static void sio_free_desc(struct sio_data *sio, struct sio_coproc_desc *desc) > +{ > + clear_bit(desc - sio->shmem_desc_base, sio->desc_allocated); > +} > + > +static int sio_coproc_desc_slot(struct sio_data *sio, struct sio_coproc_desc *desc) > +{ > + return (desc - sio->shmem_desc_base) * 4; > +} > + > +static enum dma_transfer_direction sio_chan_direction(int channo) > +{ > + /* Channel directions are fixed based on channel number */ > + return (channo & 1) ? DMA_DEV_TO_MEM : DMA_MEM_TO_DEV; > +} > + > +static void sio_tx_free(struct virt_dma_desc *vd) > +{ > + struct sio_data *sio = to_sio_chan(vd->tx.chan)->host; > + struct sio_tx *siotx = to_sio_tx(&vd->tx); > + int i; > + > + for (i = 0; i < siotx->nperiods; i++) > + if (siotx->siodesc[i]) > + sio_free_desc(sio, siotx->siodesc[i]); > + kfree(siotx); > +} > + > +static struct dma_async_tx_descriptor *sio_prep_dma_cyclic( > + struct dma_chan *chan, dma_addr_t buf_addr, size_t buf_len, > + size_t period_len, enum dma_transfer_direction direction, > + unsigned long flags) > +{ > + struct sio_chan *siochan = to_sio_chan(chan); > + struct sio_tx *siotx = NULL; > + int i, nperiods = buf_len / period_len; > + > + if (direction != sio_chan_direction(siochan->no)) > + return NULL; > + > + siotx = kzalloc(struct_size(siotx, siodesc, nperiods), GFP_NOWAIT); wasnt there a helper to do this sort of thing... > + if (!siotx) > + return NULL; > + > + init_completion(&siotx->done); > + siotx->period_len = period_len; > + siotx->nperiods = nperiods; > + > + for (i = 0; i < nperiods; i++) { > + struct sio_coproc_desc *d; > + > + siotx->siodesc[i] = d = sio_alloc_desc(siochan->host); > + if (!d) { > + sio_tx_free(&siotx->vd); > + return NULL; > + } > + > + d->flag = 1; // not sure what's up with this :-) but /* comments only */ pls > + d->iova = buf_addr + period_len * i; > + d->size = period_len; > + } > + dma_wmb(); why do you need a barrier here > + > + return vchan_tx_prep(&siochan->vc, &siotx->vd, flags); > +} > + > +static enum dma_status sio_tx_status(struct dma_chan *chan, dma_cookie_t cookie, > + struct dma_tx_state *txstate) > +{ > + struct sio_chan *siochan = to_sio_chan(chan); > + struct virt_dma_desc *vd; > + struct sio_tx *siotx; > + enum dma_status ret; > + unsigned long flags; > + int periods_residue; > + size_t residue; > + > + ret = dma_cookie_status(chan, cookie, txstate); > + if (ret == DMA_COMPLETE || !txstate) > + return ret; > + > + spin_lock_irqsave(&siochan->vc.lock, flags); > + siotx = siochan->current_tx; > + > + if (siotx && siotx->vd.tx.cookie == cookie) { > + ret = DMA_IN_PROGRESS; > + periods_residue = siotx->next - siotx->ninflight; > + while (periods_residue < 0) > + periods_residue += siotx->nperiods; > + residue = (siotx->nperiods - periods_residue) * siotx->period_len; > + } else { > + ret = DMA_IN_PROGRESS; > + residue = 0; > + vd = vchan_find_desc(&siochan->vc, cookie); > + if (vd) { > + siotx = to_sio_tx(&vd->tx); > + residue = siotx->period_len * siotx->nperiods; > + } > + } > + spin_unlock_irqrestore(&siochan->vc.lock, flags); > + dma_set_residue(txstate, residue); > + > + return ret; > +} > + > +static bool sio_fill_in_locked(struct sio_chan *siochan); > + > +static void sio_handle_issue_ack(struct sio_chan *siochan, void *cookie, bool ok) > +{ > + unsigned long flags; > + dma_cookie_t tx_cookie = (unsigned long) cookie; > + struct sio_tx *tx; reverse christmas tree style pls > + > + if (!ok) { > + dev_err(siochan->host->dev, "nacked issue on chan %d\n", siochan->no); > + return; > + } > + > + spin_lock_irqsave(&siochan->vc.lock, flags); > + if (!siochan->current_tx || tx_cookie != siochan->current_tx->vd.tx.cookie || > + siochan->current_tx->terminated) > + goto out; > + > + tx = siochan->current_tx; > + tx->next = (tx->next + 1) % tx->nperiods; > + tx->ninflight++; > + sio_fill_in_locked(siochan); > + > +out: > + spin_unlock_irqrestore(&siochan->vc.lock, flags); > +} > + > +static bool sio_fill_in_locked(struct sio_chan *siochan) > +{ > + struct sio_data *sio = siochan->host; > + struct sio_tx *tx = siochan->current_tx; > + struct sio_coproc_desc *d = tx->siodesc[tx->next]; > + int ret; > + > + if (tx->ninflight >= SIO_MAX_NINFLIGHT || tx->terminated) > + return false; > + > + static_assert(sizeof(dma_cookie_t) <= sizeof(void *)); > + ret = sio_send_siomsg_atomic(sio, FIELD_PREP(SIOMSG_EP, siochan->no) | > + FIELD_PREP(SIOMSG_TYPE, MSG_ISSUE) | > + FIELD_PREP(SIOMSG_DATA, sio_coproc_desc_slot(sio, d)), > + sio_handle_issue_ack, (void *) (uintptr_t) tx->vd.tx.cookie); > + if (ret < 0) > + dev_err_ratelimited(sio->dev, "can't issue on chan %d ninflight %d: %d\n", > + siochan->no, tx->ninflight, ret); > + return true; > +} > + > +static void sio_update_current_tx_locked(struct sio_chan *siochan) > +{ > + struct virt_dma_desc *vd = vchan_next_desc(&siochan->vc); > + > + if (vd && !siochan->current_tx) { > + list_del(&vd->node); > + siochan->current_tx = to_sio_tx(&vd->tx); > + sio_fill_in_locked(siochan); > + } > +} > + > +static void sio_issue_pending(struct dma_chan *chan) > +{ > + struct sio_chan *siochan = to_sio_chan(chan); > + unsigned long flags; > + > + spin_lock_irqsave(&siochan->vc.lock, flags); > + vchan_issue_pending(&siochan->vc); > + sio_update_current_tx_locked(siochan); > + spin_unlock_irqrestore(&siochan->vc.lock, flags); > +} > + > +static int sio_terminate_all(struct dma_chan *chan) > +{ > + struct sio_chan *siochan = to_sio_chan(chan); > + unsigned long flags; > + LIST_HEAD(to_free); > + > + spin_lock_irqsave(&siochan->vc.lock, flags); > + if (siochan->current_tx && !siochan->current_tx->terminated) { > + dma_cookie_complete(&siochan->current_tx->vd.tx); > + siochan->current_tx->terminated = true; > + schedule_work(&siochan->terminate_wq); > + } > + vchan_get_all_descriptors(&siochan->vc, &to_free); > + spin_unlock_irqrestore(&siochan->vc.lock, flags); > + > + vchan_dma_desc_free_list(&siochan->vc, &to_free); > + > + return 0; > +} > + > +static void sio_terminate_work(struct work_struct *wq) > +{ > + struct sio_chan *siochan = container_of(wq, struct sio_chan, terminate_wq); > + struct sio_tx *tx; > + unsigned long flags; > + int ret; > + > + spin_lock_irqsave(&siochan->vc.lock, flags); > + tx = siochan->current_tx; > + spin_unlock_irqrestore(&siochan->vc.lock, flags); > + > + if (WARN_ON(!tx)) > + return; > + > + ret = sio_call(siochan->host, FIELD_PREP(SIOMSG_EP, siochan->no) | > + FIELD_PREP(SIOMSG_TYPE, MSG_TERMINATE)); > + if (ret < 0) > + dev_err(siochan->host->dev, "terminate call on chan %d failed: %d\n", > + siochan->no, ret); > + > + ret = wait_for_completion_timeout(&tx->done, msecs_to_jiffies(500)); > + if (!ret) > + dev_err(siochan->host->dev, "terminate descriptor wait timed out\n"); > + > + tasklet_kill(&siochan->vc.task); > + > + spin_lock_irqsave(&siochan->vc.lock, flags); > + WARN_ON(siochan->current_tx != tx); > + siochan->current_tx = NULL; > + sio_update_current_tx_locked(siochan); > + spin_unlock_irqrestore(&siochan->vc.lock, flags); > + > + sio_tx_free(&tx->vd); > +} > + > +static void sio_synchronize(struct dma_chan *chan) > +{ > + struct sio_chan *siochan = to_sio_chan(chan); > + > + flush_work(&siochan->terminate_wq); > +} > + > +static void sio_free_chan_resources(struct dma_chan *chan) > +{ > + sio_terminate_all(chan); > + sio_synchronize(chan); > + vchan_free_chan_resources(&to_sio_chan(chan)->vc); > +} > + > +static struct dma_chan *sio_dma_of_xlate(struct of_phandle_args *dma_spec, > + struct of_dma *ofdma) > +{ > + struct sio_data *sio = (struct sio_data *) ofdma->of_dma_data; > + unsigned int index = dma_spec->args[0]; > + > + if (dma_spec->args_count != 1 || index >= sio->nchannels) > + return ERR_PTR(-EINVAL); > + > + return dma_get_slave_channel(&sio->channels[index].vc.chan); > +} > + > +static void sio_rtk_crashed(void *cookie) > +{ > + struct sio_data *sio = cookie; > + > + dev_err(sio->dev, "SIO down (crashed)"); > +} > + > +static void sio_process_report(struct sio_chan *siochan) > +{ > + unsigned long flags; > + > + spin_lock_irqsave(&siochan->vc.lock, flags); > + if (siochan->current_tx) { > + struct sio_tx *tx = siochan->current_tx; > + > + if (tx->ninflight) > + tx->ninflight--; > + vchan_cyclic_callback(&tx->vd); > + if (!sio_fill_in_locked(siochan) && !tx->ninflight) > + complete(&tx->done); > + } > + spin_unlock_irqrestore(&siochan->vc.lock, flags); > +} > + > +static void sio_recv_msg(void *cookie, u8 ep, u64 msg) > +{ > + struct sio_data *sio = cookie; > + struct sio_tagdata *tags = &sio->tags; > + u32 data; > + u8 param, type, tag, sioep; > + > + if (ep != EP_SIO) > + goto unknown; > + > + data = FIELD_GET(SIOMSG_DATA, msg); > + param = FIELD_GET(SIOMSG_PARAM, msg); > + type = FIELD_GET(SIOMSG_TYPE, msg); > + tag = FIELD_GET(SIOMSG_TAG, msg); > + sioep = FIELD_GET(SIOMSG_EP, msg); > + > + switch (type) { > + case MSG_STARTED: > + dev_info(sio->dev, "SIO protocol v%u\n", data); > + type = MSG_ACK; /* Pretend this is an ACK */ > + fallthrough; > + case MSG_ACK: > + case MSG_NACK: > + if (WARN_ON(tag >= SIO_NTAGS)) > + break; > + > + if (tags->atomic[tag]) { > + sio_ack_callback callback = tags->ack_callback[tag]; > + > + if (callback && !WARN_ON(sioep >= sio->nchannels)) > + callback(&sio->channels[sioep], > + tags->cookie[tag], type == MSG_ACK); > + if (type == MSG_NACK) > + dev_err(sio->dev, "got a NACK on channel %d\n", sioep); > + sio_free_tag(sio, tag); > + } else { > + tags->acked[tag] = (type == MSG_ACK); > + complete(&tags->completions[tag]); > + } > + break; > + > + case MSG_REPORT: > + if (WARN_ON(sioep >= sio->nchannels)) > + break; > + > + sio_process_report(&sio->channels[sioep]); > + break; > + > + default: > + goto unknown; > + } > + return; > + > +unknown: > + dev_warn(sio->dev, "received unknown message: ep %x data %016llx\n", > + ep, msg); > +} > + > +static int _sio_send_siomsg(struct sio_data *sio, u64 msg, bool atomic, > + sio_ack_callback ack_callback, void *cookie) > +{ > + int tag, ret; > + > + tag = sio_alloc_tag(sio); > + if (tag < 0) > + return tag; > + > + if (atomic) > + sio_set_tag_atomic(sio, tag, ack_callback, cookie); > + else > + reinit_completion(&sio->tags.completions[tag]); > + > + msg &= ~SIOMSG_TAG; > + msg |= FIELD_PREP(SIOMSG_TAG, tag); > + ret = apple_rtkit_send_message(sio->rtk, EP_SIO, msg, NULL, > + atomic); > + if (ret < 0) { > + sio_free_tag(sio, tag); > + return ret; > + } > + > + return tag; > +} > + > +static int sio_send_siomsg(struct sio_data *sio, u64 msg) > +{ > + return _sio_send_siomsg(sio, msg, false, NULL, NULL); > +} > + > +static int sio_send_siomsg_atomic(struct sio_data *sio, u64 msg, > + sio_ack_callback ack_callback, > + void *cookie) > +{ > + return _sio_send_siomsg(sio, msg, true, ack_callback, cookie); > +} > + > +static int sio_call(struct sio_data *sio, u64 msg) > +{ > + int tag, ret; > + > + tag = sio_send_siomsg(sio, msg); > + if (tag < 0) > + return tag; > + > + ret = wait_for_completion_timeout(&sio->tags.completions[tag], > + msecs_to_jiffies(SIO_CALL_TIMEOUT_MS)); > + if (!ret) { > + dev_warn(sio->dev, "call %8x timed out\n", msg); > + sio_free_tag(sio, tag); > + return -ETIME; > + } > + > + ret = sio->tags.acked[tag]; > + sio_free_tag(sio, tag); > + > + return ret; > +} > + > +static const struct apple_rtkit_ops sio_rtkit_ops = { > + .crashed = sio_rtk_crashed, > + .recv_message = sio_recv_msg, > +}; so we ahve a remote processor which we send message to right? > +static int sio_device_config(struct dma_chan *chan, > + struct dma_slave_config *config) > +{ > + struct sio_chan *siochan = to_sio_chan(chan); > + struct sio_data *sio = siochan->host; > + bool is_tx = sio_chan_direction(siochan->no) == DMA_MEM_TO_DEV; > + struct sio_shmem_chan_config *cfg = sio->shmem; > + int ret; > + > + switch (is_tx ? config->dst_addr_width : config->src_addr_width) { > + case DMA_SLAVE_BUSWIDTH_1_BYTE: > + cfg->datashape = 0; > + break; > + case DMA_SLAVE_BUSWIDTH_2_BYTES: > + cfg->datashape = 1; > + break; > + case DMA_SLAVE_BUSWIDTH_4_BYTES: > + cfg->datashape = 2; > + break; > + default: > + return -EINVAL; > + } > + > + cfg->fifo = 0x800; > + cfg->limit = 0x800; > + cfg->threshold = 0x800; > + dma_wmb(); ?? > + > + ret = sio_call(sio, FIELD_PREP(SIOMSG_TYPE, MSG_CONFIGURE) | > + FIELD_PREP(SIOMSG_EP, siochan->no)); this does not sound okay, can you explain why this call is here > + > + if (ret == 1) > + ret = 0; > + else if (ret == 0) > + ret = -EINVAL; > + return ret; > +} > + > +static int sio_alloc_shmem(struct sio_data *sio) > +{ > + dma_addr_t iova; > + int err; > + > + sio->shmem = dma_alloc_coherent(sio->dev, SIO_SHMEM_SIZE, > + &iova, GFP_KERNEL); > + if (!sio->shmem) > + return -ENOMEM; > + > + sio->shmem_desc_base = (struct sio_coproc_desc *) (sio->shmem + 56); > + sio->desc_allocated = devm_kzalloc(sio->dev, SIO_NO_DESC_SLOTS / 32, > + GFP_KERNEL); > + if (!sio->desc_allocated) > + return -ENOMEM; > + > + err = sio_call(sio, FIELD_PREP(SIOMSG_TYPE, MSG_SETUP) | > + FIELD_PREP(SIOMSG_PARAM, 1) | > + FIELD_PREP(SIOMSG_DATA, iova >> 12)); > + if (err != 1) { > + if (err == 0) > + err = -EINVAL; > + return err; > + } > + > + err = sio_call(sio, FIELD_PREP(SIOMSG_TYPE, MSG_SETUP) | > + FIELD_PREP(SIOMSG_PARAM, 2) | > + FIELD_PREP(SIOMSG_DATA, SIO_SHMEM_SIZE)); > + if (err != 1) { > + if (err == 0) > + err = -EINVAL; > + return err; > + } > + > + return 0; > +} > + > +static int sio_send_dt_params(struct sio_data *sio) > +{ > + struct device_node *np = sio->dev->of_node; > + const char *propname = "apple,sio-firmware-params"; > + int nparams, err, i; > + > + nparams = of_property_count_u32_elems(np, propname); > + if (nparams < 0) { > + err = nparams; > + goto badprop; > + } > + > + for (i = 0; i < nparams / 2; i++) { > + u32 key, val; > + > + err = of_property_read_u32_index(np, propname, 2 * i, &key); > + if (err) > + goto badprop; > + err = of_property_read_u32_index(np, propname, 2 * i + 1, &val); > + if (err) > + goto badprop; > + > + err = sio_call(sio, FIELD_PREP(SIOMSG_TYPE, MSG_SETUP) | > + FIELD_PREP(SIOMSG_PARAM, key & 0xff) | > + FIELD_PREP(SIOMSG_EP, key >> 8) | > + FIELD_PREP(SIOMSG_DATA, val)); > + if (err < 1) { > + if (err == 0) > + err = -ENXIO; > + return dev_err_probe(sio->dev, err, "sending SIO parameter %#x value %#x\n", > + key, val); > + } > + } > + > + return 0; > + > +badprop: > + return dev_err_probe(sio->dev, err, "failed to read '%s'\n", propname); > +} > + > +static int sio_probe(struct platform_device *pdev) > +{ > + struct device_node *np = pdev->dev.of_node; > + struct sio_data *sio; > + struct dma_device *dma; > + int nchannels; > + int err, i; > + > + err = of_property_read_u32(np, "dma-channels", &nchannels); > + if (err || nchannels > NCHANNELS_MAX) > + return dev_err_probe(&pdev->dev, -EINVAL, > + "missing or invalid dma-channels property\n"); > + > + sio = devm_kzalloc(&pdev->dev, struct_size(sio, channels, nchannels), GFP_KERNEL); > + if (!sio) > + return -ENOMEM; > + > + platform_set_drvdata(pdev, sio); > + sio->dev = &pdev->dev; > + sio->nchannels = nchannels; > + > + sio->base = devm_platform_ioremap_resource(pdev, 0); > + if (IS_ERR(sio->base)) > + return PTR_ERR(sio->base); > + > + sio->rtk = devm_apple_rtkit_init(&pdev->dev, sio, NULL, 0, &sio_rtkit_ops); > + if (IS_ERR(sio->rtk)) > + return dev_err_probe(&pdev->dev, PTR_ERR(sio->rtk), > + "couldn't initialize rtkit\n"); > + for (i = 1; i < SIO_NTAGS; i++) > + init_completion(&sio->tags.completions[i]); > + > + dma = &sio->dma; > + dma_cap_set(DMA_PRIVATE, dma->cap_mask); > + dma_cap_set(DMA_CYCLIC, dma->cap_mask); > + > + dma->dev = &pdev->dev; > + dma->device_free_chan_resources = sio_free_chan_resources; > + dma->device_tx_status = sio_tx_status; > + dma->device_issue_pending = sio_issue_pending; > + dma->device_terminate_all = sio_terminate_all; > + dma->device_synchronize = sio_synchronize; > + dma->device_prep_dma_cyclic = sio_prep_dma_cyclic; > + dma->device_config = sio_device_config; > + > + dma->directions = BIT(DMA_MEM_TO_DEV); > + dma->residue_granularity = DMA_RESIDUE_GRANULARITY_SEGMENT; > + dma->dst_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) | > + BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) | > + BIT(DMA_SLAVE_BUSWIDTH_4_BYTES); > + > + INIT_LIST_HEAD(&dma->channels); > + for (i = 0; i < nchannels; i++) { > + struct sio_chan *siochan = &sio->channels[i]; > + > + siochan->host = sio; > + siochan->no = i; > + siochan->vc.desc_free = sio_tx_free; > + INIT_WORK(&siochan->terminate_wq, sio_terminate_work); > + vchan_init(&siochan->vc, dma); > + } > + > + writel(CPU_CONTROL_RUN, sio->base + REG_CPU_CONTROL); > + > + err = apple_rtkit_boot(sio->rtk); > + if (err) > + return dev_err_probe(&pdev->dev, err, "SIO did not boot\n"); > + > + err = apple_rtkit_start_ep(sio->rtk, EP_SIO); > + if (err) > + return dev_err_probe(&pdev->dev, err, "starting SIO endpoint\n"); > + > + err = sio_call(sio, FIELD_PREP(SIOMSG_TYPE, MSG_START)); > + if (err < 1) { > + if (err == 0) > + err = -ENXIO; > + return dev_err_probe(&pdev->dev, err, "starting SIO service\n"); > + } > + > + err = sio_send_dt_params(sio); > + if (err < 0) > + return dev_err_probe(&pdev->dev, err, "failed to send boot-up parameters\n"); > + > + err = sio_alloc_shmem(sio); > + if (err < 0) > + return err; > + > + err = dma_async_device_register(&sio->dma); > + if (err) > + return dev_err_probe(&pdev->dev, err, "failed to register DMA device\n"); > + > + err = of_dma_controller_register(pdev->dev.of_node, sio_dma_of_xlate, sio); > + if (err) { > + dma_async_device_unregister(&sio->dma); > + return dev_err_probe(&pdev->dev, err, "failed to register with OF\n"); > + } > + > + return 0; > +} > + > +static int sio_remove(struct platform_device *pdev) > +{ > + struct sio_data *sio = platform_get_drvdata(pdev); > + > + of_dma_controller_free(pdev->dev.of_node); > + dma_async_device_unregister(&sio->dma); > + return 0; > +} > + > +static const struct of_device_id sio_of_match[] = { > + { .compatible = "apple,sio", }, > + { } > +}; > +MODULE_DEVICE_TABLE(of, sio_of_match); > + > +static struct platform_driver apple_sio_driver = { > + .driver = { > + .name = "apple-sio", > + .of_match_table = sio_of_match, > + }, > + .probe = sio_probe, > + .remove = sio_remove, > +}; > +module_platform_driver(apple_sio_driver); > + > +MODULE_AUTHOR("Martin Povišer <povik+lin@xxxxxxxxxxx>"); > +MODULE_DESCRIPTION("Driver for SIO coprocessor on Apple SoCs"); > +MODULE_LICENSE("Dual MIT/GPL"); > -- > 2.38.3 -- ~Vinod