libpayload: xhci: Make XHCI stack usable on ARM

This patch updates the libpayload XHCI stack to run on ARM CPUs (tested
with the DWC3 controller on an Exynos5420). Firstly, it adds support for
64-byte Slot/Endpoint Context sizes. Since the existing context handling
code represented the whole device context as a C struct (whose size has
to be known at compile time), it was necessary to refactor the input and
device context structures to consist of pointers to the actual contexts
instead.

Secondly, it moves all data structures that the xHC accesses through DMA
to cache-coherent memory. With a similar rationale as in the ARM patches
for EHCI, using explicit cache maintenance functions to correctly handle
the actual transfer buffers in all cases is presumably impossible.
Instead this patch also chooses to create a DMA bounce buffer in the
XHCI stack where transfer buffers which are not already cache-coherent
will be copied to/from.

Change-Id: I14e82fffb43b4d52d687b65415f2e33920e088de
Signed-off-by: Julius Werner <jwerner@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/169453
Reviewed-by: Stefan Reinauer <reinauer@google.com>
(cherry picked from commit 1fa9964063cce6cbd87ba68334806dde8aa2354c)
Signed-off-by: Isaac Christensen <isaac.christensen@se-eng.com>
Reviewed-on: http://review.coreboot.org/6643
Tested-by: build bot (Jenkins)
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>

1 files changed, 74 insertions, 53 deletions

diff --git a/payloads/libpayload/drivers/usb/xhci_devconf.c b/payloads/libpayload/drivers/usb/xhci_devconf.c
index 34bac8ff47..18ba4e8104 100644
--- a/payloads/libpayload/drivers/usb/xhci_devconf.c
+++ b/payloads/libpayload/drivers/usb/xhci_devconf.c
@@ -37,9 +37,7 @@ xhci_gen_route(xhci_t *const xhci, const int hubport, const int hubaddr)
 {
 	if (!hubaddr)
 		return 0;
-	volatile const devctx_t *const devctx =
-		phys_to_virt(xhci->dcbaa[hubaddr]);
-	u32 route_string = SC_GET(ROUTE, devctx->slot);
+	u32 route_string = SC_GET(ROUTE, xhci->dev[hubaddr].ctx.slot);
 	int i;
 	for (i = 0; i < 20; i += 4) {
 		if (!(route_string & (0xf << i))) {
@@ -55,9 +53,7 @@ xhci_get_rh_port(xhci_t *const xhci, const int hubport, const int hubaddr)
 {
 	if (!hubaddr)
 		return hubport;
-	volatile const devctx_t *const devctx =
-		phys_to_virt(xhci->dcbaa[hubaddr]);
-	return SC_GET(RHPORT, devctx->slot);
+	return SC_GET(RHPORT, xhci->dev[hubaddr].ctx.slot);
 }
 
 static int
@@ -67,12 +63,11 @@ xhci_get_tt(xhci_t *const xhci, const int xhci_speed,
 {
 	if (!hubaddr)
 		return 0;
-	volatile const devctx_t *const devctx =
-		phys_to_virt(xhci->dcbaa[hubaddr]);
-	if ((*tt = SC_GET(TTID, devctx->slot))) {
-		*tt_port = SC_GET(TTPORT, devctx->slot);
+	const slotctx_t *const slot = xhci->dev[hubaddr].ctx.slot;
+	if ((*tt = SC_GET(TTID, slot))) {
+		*tt_port = SC_GET(TTPORT, slot);
 	} else if (xhci_speed < XHCI_HIGH_SPEED &&
-			SC_GET(SPEED, devctx->slot) == XHCI_HIGH_SPEED) {
+			SC_GET(SPEED, slot) == XHCI_HIGH_SPEED) {
 		*tt = hubaddr;
 		*tt_port = hubport;
 	}
@@ -130,20 +125,45 @@ xhci_get_mps0(usbdev_t *const dev, const int xhci_speed)
 	}
 }
 
+static inputctx_t *
+xhci_make_inputctx(const size_t ctxsize)
+{
+	int i;
+	const size_t size = (1 + NUM_EPS) * ctxsize;
+	inputctx_t *const ic = malloc(sizeof(*ic));
+	void *dma_buffer = dma_memalign(64, size);
+
+	if (!ic || !dma_buffer) {
+		free(ic);
+		free(dma_buffer);
+		return NULL;
+	}
+
+	memset(dma_buffer, 0, size);
+	ic->drop = dma_buffer + 0;
+	ic->add = dma_buffer + 4;
+	dma_buffer += ctxsize;
+	for (i = 0; i < NUM_EPS; i++, dma_buffer += ctxsize)
+		ic->dev.ep[i] = dma_buffer;
+
+	return ic;
+}
+
 int
 xhci_set_address (hci_t *controller, int speed, int hubport, int hubaddr)
 {
 	xhci_t *const xhci = XHCI_INST(controller);
 	const int xhci_speed = speed + 1;
+	const size_t ctxsize = CTXSIZE(xhci);
+	devinfo_t *di = NULL;
 
-	int ret = -1;
+	int i, ret = -1;
 
-	inputctx_t *const ic = xhci_align(64, sizeof(*ic));
-	devinfo_t *const di = memalign(sizeof(di->devctx), sizeof(*di));
+	inputctx_t *const ic = xhci_make_inputctx(ctxsize);
 	transfer_ring_t *const tr = malloc(sizeof(*tr));
 	if (tr)
 		tr->ring = xhci_align(16, TRANSFER_RING_SIZE * sizeof(trb_t));
-	if (!ic || !di || !tr || !tr->ring) {
+	if (!ic || !tr || !tr->ring) {
 		xhci_debug("Out of memory\n");
 		goto _free_return;
 	}
@@ -157,9 +177,15 @@ xhci_set_address (hci_t *controller, int speed, int hubport, int hubaddr)
 		xhci_debug("Enabled slot %d\n", slot_id);
 	}
 
-	memset(ic, 0x00, sizeof(*ic));
-	ic->control.add = (1 << 0) /* Slot Context */ |
-			  (1 << 1) /* EP0 Context */ ;
+	di = &xhci->dev[slot_id];
+	void *dma_buffer = dma_memalign(64, NUM_EPS * ctxsize);
+	if (!dma_buffer)
+		goto _free_return;
+	memset(dma_buffer, 0, NUM_EPS * ctxsize);
+	for (i = 0; i < NUM_EPS; i++, dma_buffer += ctxsize)
+		di->ctx.ep[i] = dma_buffer;
+
+	*ic->add = (1 << 0) /* Slot Context */ | (1 << 1) /* EP0 Context */ ;
 
 	SC_SET(ROUTE,	ic->dev.slot, xhci_gen_route(xhci, hubport, hubaddr));
 	SC_SET(SPEED,	ic->dev.slot, xhci_speed);
@@ -169,27 +195,23 @@ xhci_set_address (hci_t *controller, int speed, int hubport, int hubaddr)
 	int tt, tt_port;
 	if (xhci_get_tt(xhci, xhci_speed, hubport, hubaddr, &tt, &tt_port)) {
 		xhci_debug("TT for %d: %d[%d]\n", slot_id, tt, tt_port);
-		volatile const devctx_t *const ttctx =
-			phys_to_virt(xhci->dcbaa[tt]);
-		SC_SET(MTT, ic->dev.slot, SC_GET(MTT, ttctx->slot));
+		SC_SET(MTT, ic->dev.slot, SC_GET(MTT, xhci->dev[tt].ctx.slot));
 		SC_SET(TTID, ic->dev.slot, tt);
 		SC_SET(TTPORT, ic->dev.slot, tt_port);
 	}
 
-	memset(di, 0x00, sizeof(*di));
 	di->transfer_rings[1] = tr;
 	xhci_init_cycle_ring(tr, TRANSFER_RING_SIZE);
 
-	ic->dev.ep0.tr_dq_low	= virt_to_phys(tr->ring);
-	ic->dev.ep0.tr_dq_high	= 0;
+	ic->dev.ep0->tr_dq_low	= virt_to_phys(tr->ring);
+	ic->dev.ep0->tr_dq_high	= 0;
 	EC_SET(TYPE,	ic->dev.ep0, EP_CONTROL);
 	EC_SET(AVRTRB,	ic->dev.ep0, 8);
 	EC_SET(MPS,	ic->dev.ep0, 8);
 	EC_SET(CERR,	ic->dev.ep0, 3);
 	EC_SET(DCS,	ic->dev.ep0, 1);
 
-	volatile devctx_t *const oc = &di->devctx;
-	xhci->dcbaa[slot_id] = virt_to_phys(oc);
+	xhci->dcbaa[slot_id] = virt_to_phys(di->ctx.raw);
 
 	cc = xhci_cmd_address_device(xhci, slot_id, ic);
 	if (cc != CC_SUCCESS) {
@@ -197,7 +219,7 @@ xhci_set_address (hci_t *controller, int speed, int hubport, int hubaddr)
 		goto _disable_return;
 	} else {
 		xhci_debug("Addressed device %d (USB: %d)\n",
-			  slot_id, SC_GET(UADDR, oc->slot));
+			  slot_id, SC_GET(UADDR, di->ctx.slot));
 	}
 	mdelay(2); /* SetAddress() recovery interval (usb20 spec 9.2.6.3) */
 
@@ -209,9 +231,8 @@ xhci_set_address (hci_t *controller, int speed, int hubport, int hubaddr)
 	if (mps0 < 0) {
 		goto _disable_return;
 	} else if (mps0 != 8) {
-		memset(&ic->control, 0x00, sizeof(ic->control));
-		memset(&ic->dev.ep0, 0x00, sizeof(ic->dev.ep0));
-		ic->control.add = (1 << 1); /* EP0 Context */
+		memset((void *)ic->dev.ep0, 0x00, ctxsize);
+		*ic->add = (1 << 1); /* EP0 Context */
 		EC_SET(MPS, ic->dev.ep0, mps0);
 		cc = xhci_cmd_evaluate_context(xhci, slot_id, ic);
 		if (cc != CC_SUCCESS) {
@@ -232,8 +253,12 @@ _free_return:
 	if (tr)
 		free((void *)tr->ring);
 	free(tr);
+	if (di)
+		free(di->ctx.raw);
 	free((void *)di);
 _free_ic_return:
+	if (ic)
+		free(ic->raw);
 	free(ic);
 	return ret;
 }
@@ -291,8 +316,6 @@ static int
 xhci_finish_ep_config(const endpoint_t *const ep, inputctx_t *const ic)
 {
 	xhci_t *const xhci = XHCI_INST(ep->dev->controller);
-	devinfo_t *const di = phys_to_virt(xhci->dcbaa[ep->dev->address]
-					   - offsetof(devinfo_t, devctx));
 	const int ep_id = xhci_ep_id(ep);
 	xhci_debug("ep_id: %d\n", ep_id);
 	if (ep_id <= 1 || 32 <= ep_id)
@@ -306,30 +329,30 @@ xhci_finish_ep_config(const endpoint_t *const ep, inputctx_t *const ic)
 		xhci_debug("Out of memory\n");
 		return OUT_OF_MEMORY;
 	}
-	di->transfer_rings[ep_id] = tr;
+	xhci->dev[ep->dev->address].transfer_rings[ep_id] = tr;
 	xhci_init_cycle_ring(tr, TRANSFER_RING_SIZE);
 
-	ic->control.add |= (1 << ep_id);
+	*ic->add |= (1 << ep_id);
 	if (SC_GET(CTXENT, ic->dev.slot) < ep_id)
 		SC_SET(CTXENT, ic->dev.slot, ep_id);
 
-	epctx_t *const epctx = &ic->dev.eps[ep_id];
+	epctx_t *const epctx = ic->dev.ep[ep_id];
 	xhci_debug("Filling epctx (@%p)\n", epctx);
 	epctx->tr_dq_low	= virt_to_phys(tr->ring);
 	epctx->tr_dq_high	= 0;
-	EC_SET(INTVAL,	*epctx, xhci_bound_interval(ep));
-	EC_SET(CERR,	*epctx, 3);
-	EC_SET(TYPE,	*epctx, ep->type | ((ep->direction != OUT) << 2));
-	EC_SET(MPS,	*epctx, ep->maxpacketsize);
-	EC_SET(DCS,	*epctx, 1);
+	EC_SET(INTVAL,	epctx, xhci_bound_interval(ep));
+	EC_SET(CERR,	epctx, 3);
+	EC_SET(TYPE,	epctx, ep->type | ((ep->direction != OUT) << 2));
+	EC_SET(MPS,	epctx, ep->maxpacketsize);
+	EC_SET(DCS,	epctx, 1);
 	size_t avrtrb;
 	switch (ep->type) {
 		case BULK: case ISOCHRONOUS:	avrtrb = 3 * 1024; break;
 		case INTERRUPT:			avrtrb =     1024; break;
 		default:			avrtrb =        8; break;
 	}
-	EC_SET(AVRTRB,	*epctx, avrtrb);
-	EC_SET(MXESIT,  *epctx, EC_GET(MPS, *epctx) * EC_GET(MBS, *epctx));
+	EC_SET(AVRTRB,	epctx, avrtrb);
+	EC_SET(MXESIT,  epctx, EC_GET(MPS, epctx) * EC_GET(MBS, epctx));
 
 	return 0;
 }
@@ -338,24 +361,22 @@ int
 xhci_finish_device_config(usbdev_t *const dev)
 {
 	xhci_t *const xhci = XHCI_INST(dev->controller);
-	devinfo_t *const di = phys_to_virt(xhci->dcbaa[dev->address]
-					   - offsetof(devinfo_t, devctx));
+	devinfo_t *const di = &xhci->dev[dev->address];
 
 	int i, ret = 0;
 
-	inputctx_t *const ic = xhci_align(64, sizeof(*ic));
+	inputctx_t *const ic = xhci_make_inputctx(CTXSIZE(xhci));
 	if (!ic) {
 		xhci_debug("Out of memory\n");
 		return OUT_OF_MEMORY;
 	}
-	memset(ic, 0x00, sizeof(*ic));
 
-	ic->control.add = (1 << 0); /* Slot Context */
+	*ic->add = (1 << 0); /* Slot Context */
 
-	xhci_dump_slotctx((const slotctx_t *)&di->devctx.slot);
-	ic->dev.slot.f1 = di->devctx.slot.f1;
-	ic->dev.slot.f2 = di->devctx.slot.f2;
-	ic->dev.slot.f3 = di->devctx.slot.f3;
+	xhci_dump_slotctx(di->ctx.slot);
+	ic->dev.slot->f1 = di->ctx.slot->f1;
+	ic->dev.slot->f2 = di->ctx.slot->f2;
+	ic->dev.slot->f3 = di->ctx.slot->f3;
 
 	if (((device_descriptor_t *)dev->descriptor)->bDeviceClass == 0x09) {
 		ret = xhci_finish_hub_config(dev, ic);
@@ -394,6 +415,7 @@ _free_ep_ctx_return:
 		di->transfer_rings[i] = NULL;
 	}
 _free_return:
+	free(ic->raw);
 	free(ic);
 	return ret;
 }
@@ -412,7 +434,7 @@ xhci_destroy_dev(hci_t *const controller, const int slot_id)
 	if (cc != CC_SUCCESS)
 		xhci_debug("Failed to disable slot %d: %d\n", slot_id, cc);
 
-	devinfo_t *const di = DEVINFO_FROM_XHCI(xhci, slot_id);
+	devinfo_t *const di = &xhci->dev[slot_id];
 	for (i = 1; i < 31; ++i) {
 		if (di->transfer_rings[i])
 			free((void *)di->transfer_rings[i]->ring);
@@ -420,6 +442,5 @@ xhci_destroy_dev(hci_t *const controller, const int slot_id)
 
 		free(di->interrupt_queues[i]);
 	}
-	free(di);
 	xhci->dcbaa[slot_id] = 0;
 }