usb: musb dma: add cppi41 dma driver
This driver is currently used by musb' cppi41 couter part. I may merge
both dma engine user of musb at some point but not just yet.
The driver seems to work in RX/TX mode in host mode, tested on mass
storage. I increaed the size of the TX / RX transfers and waited for the
core code to cancel a transfers and it seems to recover.
v2..3:
- use mall transfers on RX side and check data toggle.
- use rndis mode on tx side so we haveon interrupt for 4096 transfers.
- remove custom "transferred" hack and use dmaengine_tx_status() to
compute the total amount of data that has been transferred.
- cancel transfers and reclaim descriptors
v1..v2:
- RX path added
- dma mode 0 & 1 is working
- device tree nodes re-created.
Cc: Vinod Koul <vinod.koul@intel.com>
Cc: Dan Williams <djbw@fb.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Felipe Balbi <balbi@ti.com>
diff --git a/drivers/usb/musb/Kconfig b/drivers/usb/musb/Kconfig
index b7257ae..04658d7 100644
--- a/drivers/usb/musb/Kconfig
+++ b/drivers/usb/musb/Kconfig
@@ -129,6 +129,10 @@
help
Enable DMA transfers when TI CPPI DMA is available.
+config USB_TI_CPPI41_DMA
+ bool 'TI CPPI 4.1 (AM335x)'
+ depends on ARCH_OMAP
+
config USB_TUSB_OMAP_DMA
bool 'TUSB 6010'
depends on USB_MUSB_TUSB6010
diff --git a/drivers/usb/musb/Makefile b/drivers/usb/musb/Makefile
index 52f552c..c5ea5c6 100644
--- a/drivers/usb/musb/Makefile
+++ b/drivers/usb/musb/Makefile
@@ -32,3 +32,4 @@
musb_hdrc-$(CONFIG_USB_TI_CPPI_DMA) += cppi_dma.o
musb_hdrc-$(CONFIG_USB_TUSB_OMAP_DMA) += tusb6010_omap.o
musb_hdrc-$(CONFIG_USB_UX500_DMA) += ux500_dma.o
+musb_hdrc-$(CONFIG_USB_TI_CPPI41_DMA) += musb_cppi41.o
diff --git a/drivers/usb/musb/musb_cppi41.c b/drivers/usb/musb/musb_cppi41.c
new file mode 100644
index 0000000..a74259e
--- /dev/null
+++ b/drivers/usb/musb/musb_cppi41.c
@@ -0,0 +1,552 @@
+#include <linux/device.h>
+#include <linux/dma-mapping.h>
+#include <linux/dmaengine.h>
+#include <linux/sizes.h>
+#include <linux/platform_device.h>
+#include <linux/of.h>
+
+#include "musb_core.h"
+
+#define RNDIS_REG(x) (0x80 + ((x - 1) * 4))
+
+#define EP_MODE_AUTOREG_NONE 0
+#define EP_MODE_AUTOREG_ALL_NEOP 1
+#define EP_MODE_AUTOREG_ALWAYS 3
+
+#define EP_MODE_DMA_TRANSPARENT 0
+#define EP_MODE_DMA_RNDIS 1
+#define EP_MODE_DMA_GEN_RNDIS 3
+
+#define USB_CTRL_TX_MODE 0x70
+#define USB_CTRL_RX_MODE 0x74
+#define USB_CTRL_AUTOREQ 0xd0
+#define USB_TDOWN 0xd8
+
+struct cppi41_dma_channel {
+ struct dma_channel channel;
+ struct cppi41_dma_controller *controller;
+ struct musb_hw_ep *hw_ep;
+ struct dma_chan *dc;
+ dma_cookie_t cookie;
+ u8 port_num;
+ u8 is_tx;
+ u8 is_allocated;
+ u8 usb_toggle;
+
+ dma_addr_t buf_addr;
+ u32 total_len;
+ u32 prog_len;
+ u32 transferred;
+ u32 packet_sz;
+};
+
+#define MUSB_DMA_NUM_CHANNELS 15
+
+struct cppi41_dma_controller {
+ struct dma_controller controller;
+ struct cppi41_dma_channel rx_channel[MUSB_DMA_NUM_CHANNELS];
+ struct cppi41_dma_channel tx_channel[MUSB_DMA_NUM_CHANNELS];
+ struct musb *musb;
+ u32 rx_mode;
+ u32 tx_mode;
+ u32 auto_req;
+};
+
+static void save_rx_toggle(struct cppi41_dma_channel *cppi41_channel)
+{
+ u16 csr;
+ u8 toggle;
+
+ if (cppi41_channel->is_tx)
+ return;
+ if (!is_host_active(cppi41_channel->controller->musb))
+ return;
+
+ csr = musb_readw(cppi41_channel->hw_ep->regs, MUSB_RXCSR);
+ toggle = csr & MUSB_RXCSR_H_DATATOGGLE ? 1 : 0;
+
+ cppi41_channel->usb_toggle = toggle;
+}
+
+static void update_rx_toggle(struct cppi41_dma_channel *cppi41_channel)
+{
+ u16 csr;
+ u8 toggle;
+
+ if (cppi41_channel->is_tx)
+ return;
+ if (!is_host_active(cppi41_channel->controller->musb))
+ return;
+
+ csr = musb_readw(cppi41_channel->hw_ep->regs, MUSB_RXCSR);
+ toggle = csr & MUSB_RXCSR_H_DATATOGGLE ? 1 : 0;
+
+ /*
+ * AM335x Advisory 1.0.13: Due to internal synchronisation error the
+ * data toggle may reset from DATA1 to DATA0 during receiving data from
+ * more than one endpoint.
+ */
+ if (!toggle && toggle == cppi41_channel->usb_toggle) {
+ csr |= MUSB_RXCSR_H_DATATOGGLE | MUSB_RXCSR_H_WR_DATATOGGLE;
+ musb_writew(cppi41_channel->hw_ep->regs, MUSB_RXCSR, csr);
+ dev_dbg(cppi41_channel->controller->musb->controller,
+ "Restoring DATA1 toggle.\n");
+ }
+
+ cppi41_channel->usb_toggle = toggle;
+}
+
+static void cppi41_dma_callback(void *private_data)
+{
+ struct dma_channel *channel = private_data;
+ struct cppi41_dma_channel *cppi41_channel = channel->private_data;
+ struct musb_hw_ep *hw_ep = cppi41_channel->hw_ep;
+ struct musb *musb = hw_ep->musb;
+ unsigned long flags;
+ struct dma_tx_state txstate;
+ u32 transferred;
+
+ spin_lock_irqsave(&musb->lock, flags);
+
+ dmaengine_tx_status(cppi41_channel->dc, cppi41_channel->cookie,
+ &txstate);
+ transferred = cppi41_channel->prog_len - txstate.residue;
+ cppi41_channel->transferred += transferred;
+
+ dev_dbg(musb->controller, "DMA transfer done on hw_ep=%d bytes=%d/%d\n",
+ hw_ep->epnum, cppi41_channel->transferred,
+ cppi41_channel->total_len);
+
+ update_rx_toggle(cppi41_channel);
+
+ if (cppi41_channel->transferred == cppi41_channel->total_len ||
+ transferred < cppi41_channel->packet_sz) {
+
+ /* done, complete */
+ cppi41_channel->channel.actual_len =
+ cppi41_channel->transferred;
+ cppi41_channel->channel.status = MUSB_DMA_STATUS_FREE;
+ musb_dma_completion(musb, hw_ep->epnum, cppi41_channel->is_tx);
+ } else {
+ /* next iteration, reload */
+ struct dma_chan *dc = cppi41_channel->dc;
+ struct dma_async_tx_descriptor *dma_desc;
+ enum dma_transfer_direction direction;
+ u16 csr;
+ u32 remain_bytes;
+ void __iomem *epio = cppi41_channel->hw_ep->regs;
+
+ cppi41_channel->buf_addr += cppi41_channel->packet_sz;
+
+ remain_bytes = cppi41_channel->total_len;
+ remain_bytes -= cppi41_channel->transferred;
+ remain_bytes = min(remain_bytes, cppi41_channel->packet_sz);
+ cppi41_channel->prog_len = remain_bytes;
+
+ direction = cppi41_channel->is_tx ? DMA_MEM_TO_DEV
+ : DMA_DEV_TO_MEM;
+ dma_desc = dmaengine_prep_slave_single(dc,
+ cppi41_channel->buf_addr,
+ remain_bytes,
+ direction,
+ DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
+ if (WARN_ON(!dma_desc))
+ return;
+
+ dma_desc->callback = cppi41_dma_callback;
+ dma_desc->callback_param = channel;
+ cppi41_channel->cookie = dma_desc->tx_submit(dma_desc);
+ dma_async_issue_pending(dc);
+
+ if (!cppi41_channel->is_tx) {
+ csr = musb_readw(epio, MUSB_RXCSR);
+ csr |= MUSB_RXCSR_H_REQPKT;
+ musb_writew(epio, MUSB_RXCSR, csr);
+ }
+ }
+ spin_unlock_irqrestore(&musb->lock, flags);
+}
+
+static u32 update_ep_mode(unsigned ep, unsigned mode, u32 old)
+{
+ unsigned shift;
+
+ shift = (ep - 1) * 2;
+ old &= ~(3 << shift);
+ old |= mode << shift;
+ return old;
+}
+
+static void cppi41_set_dma_mode(struct cppi41_dma_channel *cppi41_channel,
+ unsigned mode)
+{
+ struct cppi41_dma_controller *controller = cppi41_channel->controller;
+ u32 port;
+ u32 new_mode;
+ u32 old_mode;
+
+ if (cppi41_channel->is_tx)
+ old_mode = controller->tx_mode;
+ else
+ old_mode = controller->rx_mode;
+ port = cppi41_channel->port_num;
+ new_mode = update_ep_mode(port, mode, old_mode);
+
+ if (new_mode == old_mode)
+ return;
+ if (cppi41_channel->is_tx) {
+ controller->tx_mode = new_mode;
+ musb_writel(controller->musb->ctrl_base, USB_CTRL_TX_MODE,
+ new_mode);
+ } else {
+ controller->rx_mode = new_mode;
+ musb_writel(controller->musb->ctrl_base, USB_CTRL_RX_MODE,
+ new_mode);
+ }
+}
+
+static void cppi41_set_autoreq_mode(struct cppi41_dma_channel *cppi41_channel,
+ unsigned mode)
+{
+ struct cppi41_dma_controller *controller = cppi41_channel->controller;
+ u32 port;
+ u32 new_mode;
+ u32 old_mode;
+
+ old_mode = controller->auto_req;
+ port = cppi41_channel->port_num;
+ new_mode = update_ep_mode(port, mode, old_mode);
+
+ if (new_mode == old_mode)
+ return;
+ controller->auto_req = new_mode;
+ musb_writel(controller->musb->ctrl_base, USB_CTRL_AUTOREQ, new_mode);
+}
+
+static bool cppi41_configure_channel(struct dma_channel *channel,
+ u16 packet_sz, u8 mode,
+ dma_addr_t dma_addr, u32 len)
+{
+ struct cppi41_dma_channel *cppi41_channel = channel->private_data;
+ struct dma_chan *dc = cppi41_channel->dc;
+ struct dma_async_tx_descriptor *dma_desc;
+ enum dma_transfer_direction direction;
+ struct musb *musb = cppi41_channel->controller->musb;
+ unsigned use_gen_rndis = 0;
+
+ dev_dbg(musb->controller,
+ "configure ep%d/%x packet_sz=%d, mode=%d, dma_addr=0x%llx, len=%d is_tx=%d\n",
+ cppi41_channel->port_num, RNDIS_REG(cppi41_channel->port_num),
+ packet_sz, mode, (unsigned long long) dma_addr,
+ len, cppi41_channel->is_tx);
+
+ cppi41_channel->buf_addr = dma_addr;
+ cppi41_channel->total_len = len;
+ cppi41_channel->transferred = 0;
+ cppi41_channel->packet_sz = packet_sz;
+
+ /*
+ * Due to AM335x' Advisory 1.0.13 we are not allowed to transfer more
+ * than max packet size at a time.
+ */
+ if (cppi41_channel->is_tx)
+ use_gen_rndis = 1;
+
+ if (use_gen_rndis) {
+ /* RNDIS mode */
+ if (len > packet_sz) {
+ musb_writel(musb->ctrl_base,
+ RNDIS_REG(cppi41_channel->port_num), len);
+ /* gen rndis */
+ cppi41_set_dma_mode(cppi41_channel,
+ EP_MODE_DMA_GEN_RNDIS);
+
+ /* auto req */
+ cppi41_set_autoreq_mode(cppi41_channel,
+ EP_MODE_AUTOREG_ALL_NEOP);
+ } else {
+ musb_writel(musb->ctrl_base,
+ RNDIS_REG(cppi41_channel->port_num), 0);
+ cppi41_set_dma_mode(cppi41_channel,
+ EP_MODE_DMA_TRANSPARENT);
+ cppi41_set_autoreq_mode(cppi41_channel,
+ EP_MODE_AUTOREG_NONE);
+ }
+ } else {
+ /* fallback mode */
+ cppi41_set_dma_mode(cppi41_channel, EP_MODE_DMA_TRANSPARENT);
+ cppi41_set_autoreq_mode(cppi41_channel, EP_MODE_AUTOREG_NONE);
+ len = min_t(u32, packet_sz, len);
+ }
+ cppi41_channel->prog_len = len;
+ direction = cppi41_channel->is_tx ? DMA_MEM_TO_DEV : DMA_DEV_TO_MEM;
+ dma_desc = dmaengine_prep_slave_single(dc, dma_addr, len, direction,
+ DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
+ if (!dma_desc)
+ return false;
+
+ dma_desc->callback = cppi41_dma_callback;
+ dma_desc->callback_param = channel;
+ cppi41_channel->cookie = dma_desc->tx_submit(dma_desc);
+
+ save_rx_toggle(cppi41_channel);
+ dma_async_issue_pending(dc);
+ return true;
+}
+
+static struct dma_channel *cppi41_dma_channel_allocate(struct dma_controller *c,
+ struct musb_hw_ep *hw_ep, u8 is_tx)
+{
+ struct cppi41_dma_controller *controller = container_of(c,
+ struct cppi41_dma_controller, controller);
+ struct cppi41_dma_channel *cppi41_channel = NULL;
+ u8 ch_num = hw_ep->epnum - 1;
+
+ if (ch_num >= MUSB_DMA_NUM_CHANNELS)
+ return NULL;
+
+ if (is_tx)
+ cppi41_channel = &controller->tx_channel[ch_num];
+ else
+ cppi41_channel = &controller->rx_channel[ch_num];
+
+ if (!cppi41_channel->dc)
+ return NULL;
+
+ if (cppi41_channel->is_allocated)
+ return NULL;
+
+ cppi41_channel->hw_ep = hw_ep;
+ cppi41_channel->is_allocated = 1;
+
+ return &cppi41_channel->channel;
+}
+
+static void cppi41_dma_channel_release(struct dma_channel *channel)
+{
+ struct cppi41_dma_channel *cppi41_channel = channel->private_data;
+
+ if (cppi41_channel->is_allocated) {
+ cppi41_channel->is_allocated = 0;
+ channel->status = MUSB_DMA_STATUS_FREE;
+ channel->actual_len = 0;
+ }
+}
+
+static int cppi41_dma_channel_program(struct dma_channel *channel,
+ u16 packet_sz, u8 mode,
+ dma_addr_t dma_addr, u32 len)
+{
+ int ret;
+
+ BUG_ON(channel->status == MUSB_DMA_STATUS_UNKNOWN ||
+ channel->status == MUSB_DMA_STATUS_BUSY);
+
+ channel->status = MUSB_DMA_STATUS_BUSY;
+ channel->actual_len = 0;
+ ret = cppi41_configure_channel(channel, packet_sz, mode, dma_addr, len);
+ if (!ret)
+ channel->status = MUSB_DMA_STATUS_FREE;
+
+ return ret;
+}
+
+static int cppi41_is_compatible(struct dma_channel *channel, u16 maxpacket,
+ void *buf, u32 length)
+{
+ struct cppi41_dma_channel *cppi41_channel = channel->private_data;
+ struct cppi41_dma_controller *controller = cppi41_channel->controller;
+ struct musb *musb = controller->musb;
+
+ if (is_host_active(musb)) {
+ WARN_ON(1);
+ return 1;
+ }
+ return 0;
+}
+
+static int cppi41_dma_channel_abort(struct dma_channel *channel)
+{
+ struct cppi41_dma_channel *cppi41_channel = channel->private_data;
+ struct cppi41_dma_controller *controller = cppi41_channel->controller;
+ struct musb *musb = controller->musb;
+ void __iomem *epio = cppi41_channel->hw_ep->regs;
+ int tdbit;
+ int ret;
+ unsigned is_tx;
+ u16 csr;
+
+ is_tx = cppi41_channel->is_tx;
+ dev_dbg(musb->controller, "abort channel=%d, is_tx=%d\n",
+ cppi41_channel->port_num, is_tx);
+
+ if (cppi41_channel->channel.status == MUSB_DMA_STATUS_FREE)
+ return 0;
+
+ if (is_tx) {
+ csr = musb_readw(epio, MUSB_TXCSR);
+ csr &= ~MUSB_TXCSR_DMAENAB;
+ musb_writew(epio, MUSB_TXCSR, csr);
+ } else {
+ csr = musb_readw(epio, MUSB_RXCSR);
+ csr &= ~(MUSB_RXCSR_H_REQPKT | MUSB_RXCSR_DMAENAB);
+ musb_writew(epio, MUSB_RXCSR, csr);
+
+ csr = musb_readw(epio, MUSB_RXCSR);
+ if (csr & MUSB_RXCSR_RXPKTRDY) {
+ csr |= MUSB_RXCSR_FLUSHFIFO;
+ musb_writew(epio, MUSB_RXCSR, csr);
+ musb_writew(epio, MUSB_RXCSR, csr);
+ }
+ }
+
+ tdbit = 1 << cppi41_channel->port_num;
+ if (is_tx)
+ tdbit <<= 16;
+
+ do {
+ musb_writel(musb->ctrl_base, USB_TDOWN, tdbit);
+ ret = dmaengine_terminate_all(cppi41_channel->dc);
+ } while (ret == -EAGAIN);
+
+ musb_writel(musb->ctrl_base, USB_TDOWN, tdbit);
+
+ if (is_tx) {
+ csr = musb_readw(epio, MUSB_TXCSR);
+ if (csr & MUSB_TXCSR_TXPKTRDY) {
+ csr |= MUSB_TXCSR_FLUSHFIFO;
+ musb_writew(epio, MUSB_TXCSR, csr);
+ }
+ }
+
+ cppi41_channel->channel.status = MUSB_DMA_STATUS_FREE;
+ return 0;
+}
+
+static void cppi41_release_all_dma_chans(struct cppi41_dma_controller *ctrl)
+{
+ struct dma_chan *dc;
+ int i;
+
+ for (i = 0; i < MUSB_DMA_NUM_CHANNELS; i++) {
+ dc = ctrl->tx_channel[i].dc;
+ if (dc)
+ dma_release_channel(dc);
+ dc = ctrl->rx_channel[i].dc;
+ if (dc)
+ dma_release_channel(dc);
+ }
+}
+
+static void cppi41_dma_controller_stop(struct cppi41_dma_controller *controller)
+{
+ cppi41_release_all_dma_chans(controller);
+}
+
+static int cppi41_dma_controller_start(struct cppi41_dma_controller *controller)
+{
+ struct musb *musb = controller->musb;
+ struct device *dev = musb->controller;
+ struct device_node *np = dev->of_node;
+ struct cppi41_dma_channel *cppi41_channel;
+ int count;
+ int i;
+ int ret;
+
+ count = of_property_count_strings(np, "dma-names");
+ if (count < 0)
+ return count;
+
+ for (i = 0; i < count; i++) {
+ struct dma_chan *dc;
+ struct dma_channel *musb_dma;
+ const char *str;
+ unsigned is_tx;
+ unsigned int port;
+
+ ret = of_property_read_string_index(np, "dma-names", i, &str);
+ if (ret)
+ goto err;
+ if (!strncmp(str, "tx", 2))
+ is_tx = 1;
+ else if (!strncmp(str, "rx", 2))
+ is_tx = 0;
+ else {
+ dev_err(dev, "Wrong dmatype %s\n", str);
+ goto err;
+ }
+ ret = kstrtouint(str + 2, 0, &port);
+ if (ret)
+ goto err;
+
+ if (port > MUSB_DMA_NUM_CHANNELS || !port)
+ goto err;
+ if (is_tx)
+ cppi41_channel = &controller->tx_channel[port - 1];
+ else
+ cppi41_channel = &controller->rx_channel[port - 1];
+
+ cppi41_channel->controller = controller;
+ cppi41_channel->port_num = port;
+ cppi41_channel->is_tx = is_tx;
+
+ musb_dma = &cppi41_channel->channel;
+ musb_dma->private_data = cppi41_channel;
+ musb_dma->status = MUSB_DMA_STATUS_FREE;
+ musb_dma->max_len = SZ_4M;
+
+ dc = dma_request_slave_channel(dev, str);
+ if (!dc) {
+ dev_err(dev, "Falied to request %s.\n", str);
+ goto err;
+ }
+ cppi41_channel->dc = dc;
+ }
+ return 0;
+err:
+ cppi41_release_all_dma_chans(controller);
+ return -EINVAL;
+}
+
+void dma_controller_destroy(struct dma_controller *c)
+{
+ struct cppi41_dma_controller *controller = container_of(c,
+ struct cppi41_dma_controller, controller);
+
+ cppi41_dma_controller_stop(controller);
+ kfree(controller);
+}
+
+struct dma_controller *dma_controller_create(struct musb *musb,
+ void __iomem *base)
+{
+ struct cppi41_dma_controller *controller;
+ int ret;
+
+ if (!musb->controller->of_node) {
+ dev_err(musb->controller, "Need DT for the DMA engine.\n");
+ return NULL;
+ }
+
+ controller = kzalloc(sizeof(*controller), GFP_KERNEL);
+ if (!controller)
+ goto kzalloc_fail;
+
+ controller->musb = musb;
+
+ controller->controller.channel_alloc = cppi41_dma_channel_allocate;
+ controller->controller.channel_release = cppi41_dma_channel_release;
+ controller->controller.channel_program = cppi41_dma_channel_program;
+ controller->controller.channel_abort = cppi41_dma_channel_abort;
+ controller->controller.is_compatible = cppi41_is_compatible;
+
+ ret = cppi41_dma_controller_start(controller);
+ if (ret)
+ goto plat_get_fail;
+ return &controller->controller;
+
+plat_get_fail:
+ kfree(controller);
+kzalloc_fail:
+ return NULL;
+}
diff --git a/drivers/usb/musb/musb_dma.h b/drivers/usb/musb/musb_dma.h
index c8e67fd..1345a4f 100644
--- a/drivers/usb/musb/musb_dma.h
+++ b/drivers/usb/musb/musb_dma.h
@@ -68,7 +68,7 @@
#define is_dma_capable() (1)
#endif
-#ifdef CONFIG_USB_TI_CPPI_DMA
+#if defined(CONFIG_USB_TI_CPPI_DMA) || defined(CONFIG_USB_TI_CPPI41_DMA)
#define is_cppi_enabled() 1
#else
#define is_cppi_enabled() 0