libpayload: Remove bitfield use from OHCI data structures

We agreed that bitfields are a Bad Idea[tm].

Change-Id: Ic04f151091c359912835b8b3db488d2d41bd4bbb
Signed-off-by: Patrick Georgi <patrick.georgi@secunet.com>
Reviewed-on: http://review.coreboot.org/479
Tested-by: build bot (Jenkins)
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
Reviewed-by: Peter Stuge <peter@stuge.se>

2 files changed, 65 insertions, 80 deletions

diff --git a/payloads/libpayload/drivers/usb/ohci.c b/payloads/libpayload/drivers/usb/ohci.c
index 60866d80d9..4095d693a6 100644
--- a/payloads/libpayload/drivers/usb/ohci.c
+++ b/payloads/libpayload/drivers/usb/ohci.c
@@ -188,7 +188,8 @@ dump_td(td_t *cur, int level)
 #ifdef USB_DEBUG
 	static const char *spaces="          ";
 	const char *spc=spaces+(10-level);
-	debug("%std at %x (%s), condition code: %s\n", spc, cur, direction[cur->direction], completion_codes[cur->condition_code & 0xf]);
+	debug("%std at %x (%s), condition code: %s\n", spc, cur, direction[(cur->config & TD_DIRECTION_MASK) >> TD_DIRECTION_SHIFT],
+		completion_codes[(cur->config & TD_CC_MASK) >> TD_CC_SHIFT]);
 	debug("%s toggle: %x\n", spc, cur->toggle);
 #endif
 }
@@ -201,7 +202,7 @@ wait_for_ed(usbdev_t *dev, ed_t *head)
 	/* wait for results */
 	while (((head->head_pointer & ~3) != head->tail_pointer) &&
 		!(head->head_pointer & 1) &&
-		((((td_t*)phys_to_virt(head->head_pointer & ~3))->condition_code & 0xf)>=0xe)) {
+		((((td_t*)phys_to_virt(head->head_pointer & ~3))->config & TD_CC_MASK) >= TD_CC_NOACCESS)) {
 		debug("intst: %x; ctrl: %x; cmdst: %x; head: %x -> %x, tail: %x, condition: %x\n",
 			OHCI_INST(dev->controller)->opreg->HcInterruptStatus,
 			OHCI_INST(dev->controller)->opreg->HcControl,
@@ -209,7 +210,7 @@ wait_for_ed(usbdev_t *dev, ed_t *head)
 			head->head_pointer,
 			((td_t*)phys_to_virt(head->head_pointer & ~3))->next_td,
 			head->tail_pointer,
-			((td_t*)phys_to_virt(head->head_pointer & ~3))->condition_code);
+			(((td_t*)phys_to_virt(head->head_pointer & ~3))->config & TD_CC_MASK) >> TD_CC_SHIFT);
 		mdelay(1);
 	}
 	mdelay(5);
@@ -266,12 +267,11 @@ ohci_control (usbdev_t *dev, direction_t dir, int drlen, void *devreq, int dalen
 	}
 	tds[td_count + 3].next_td = 0;
 
-	tds[0].direction = OHCI_SETUP;
-	tds[0].toggle_from_td = 1;
-	tds[0].toggle = 0;
-	tds[0].error_count = 0;
-	tds[0].delay_interrupt = 7;
-	tds[0].condition_code = 0xf;
+	tds[0].config = TD_DIRECTION_SETUP |
+		TD_DELAY_INTERRUPT_NODELAY |
+		TD_TOGGLE_FROM_TD |
+		TD_TOGGLE_DATA0 |
+		TD_CC_NOACCESS;
 	tds[0].current_buffer_pointer = virt_to_phys(devreq);
 	tds[0].buffer_end = virt_to_phys(devreq + drlen - 1);
 
@@ -279,12 +279,10 @@ ohci_control (usbdev_t *dev, direction_t dir, int drlen, void *devreq, int dalen
 
 	while (pages > 0) {
 		cur++;
-		cur->direction = (dir==IN)?OHCI_IN:OHCI_OUT;
-		cur->toggle_from_td = 0;
-		cur->toggle = 1;
-		cur->error_count = 0;
-		cur->delay_interrupt = 7;
-		cur->condition_code = 0xf;
+		cur->config = (dir==IN)?TD_DIRECTION_IN:TD_DIRECTION_OUT |
+			TD_DELAY_INTERRUPT_NODELAY |
+			TD_TOGGLE_FROM_ED |
+			TD_CC_NOACCESS;
 		cur->current_buffer_pointer = virt_to_phys(data);
 		pages--;
 		int consumed = (4096 - ((unsigned long)data % 4096));
@@ -308,12 +306,11 @@ ohci_control (usbdev_t *dev, direction_t dir, int drlen, void *devreq, int dalen
 	}
 
 	cur++;
-	cur->direction = (dir==IN)?OHCI_OUT:OHCI_IN;
-	cur->toggle_from_td = 1;
-	cur->toggle = 1;
-	cur->error_count = 0;
-	cur->delay_interrupt = 7;
-	cur->condition_code = 0xf;
+	cur->config = (dir==IN)?TD_DIRECTION_OUT:TD_DIRECTION_IN |
+		TD_DELAY_INTERRUPT_NODELAY |
+		TD_TOGGLE_FROM_TD |
+		TD_TOGGLE_DATA1 |
+		TD_CC_NOACCESS;
 	cur->current_buffer_pointer = 0;
 	cur->buffer_end = 0;
 
@@ -323,18 +320,15 @@ ohci_control (usbdev_t *dev, direction_t dir, int drlen, void *devreq, int dalen
 	/* Data structures */
 	ed_t *head = memalign(sizeof(ed_t), sizeof(ed_t));
 	memset((void*)head, 0, sizeof(*head));
-	head->function_address = dev->address;
-	head->endpoint_number = 0;
-	head->direction = OHCI_FROM_TD;
-	head->lowspeed = dev->speed;
-	head->format = 0;
-	head->maximum_packet_size = dev->endpoints[0].maxpacketsize;
+	head->config = (dev->address << ED_FUNC_SHIFT) |
+		(0 << ED_EP_SHIFT) |
+		(OHCI_FROM_TD << ED_DIR_SHIFT) |
+		(dev->speed?ED_LOWSPEED:0) |
+		(dev->endpoints[0].maxpacketsize << ED_MPS_SHIFT);
 	head->tail_pointer = virt_to_phys(cur);
 	head->head_pointer = virt_to_phys(tds);
-	head->halted = 0;
-	head->toggle = 0;
 
-	debug("doing control transfer with %x. first_td at %x\n", head->function_address, virt_to_phys(tds));
+	debug("doing control transfer with %x. first_td at %x\n", head->config & ED_FUNC_MASK, virt_to_phys(tds));
 
 	/* activate schedule */
 	OHCI_INST(dev->controller)->opreg->HcControlHeadED = virt_to_phys(head);
@@ -379,11 +373,10 @@ ohci_bulk (endpoint_t *ep, int dalen, u8 *data, int finalize)
 	}
 
 	for (cur = tds; cur->next_td != 0; cur++) {
-		cur->toggle_from_td = 0;
-		cur->error_count = 0;
-		cur->delay_interrupt = 7;
-		cur->condition_code = 0xf;
-		cur->direction = (ep->direction==IN)?OHCI_IN:OHCI_OUT;
+		cur->config =  (ep->direction==IN)?TD_DIRECTION_IN:TD_DIRECTION_OUT |
+                        TD_DELAY_INTERRUPT_NODELAY |
+                        TD_TOGGLE_FROM_ED |
+                        TD_CC_NOACCESS;
 		cur->current_buffer_pointer = virt_to_phys(data);
 		pages--;
 		if (dalen == 0) {
@@ -415,18 +408,16 @@ ohci_bulk (endpoint_t *ep, int dalen, u8 *data, int finalize)
 	/* Data structures */
 	ed_t *head = memalign(sizeof(ed_t), sizeof(ed_t));
 	memset((void*)head, 0, sizeof(*head));
-	head->function_address = ep->dev->address;
-	head->endpoint_number = ep->endpoint & 0xf;
-	head->direction = (ep->direction==IN)?OHCI_IN:OHCI_OUT;
-	head->lowspeed = ep->dev->speed;
-	head->format = 0;
-	head->maximum_packet_size = ep->maxpacketsize;
+	head->config = (ep->dev->address << ED_FUNC_SHIFT) |
+		((ep->endpoint & 0xf) << ED_EP_SHIFT) |
+		(((ep->direction==IN)?OHCI_IN:OHCI_OUT) << ED_DIR_SHIFT) |
+		(ep->dev->speed?ED_LOWSPEED:0) |
+		(ep->maxpacketsize << ED_MPS_SHIFT);
 	head->tail_pointer = virt_to_phys(cur);
-	head->head_pointer = virt_to_phys(tds);
-	head->halted = 0;
-	head->toggle = ep->toggle;
+	head->head_pointer = virt_to_phys(tds) | (ep->toggle?ED_TOGGLE:0);
 
-	debug("doing bulk transfer with %x(%x). first_td at %x, last %x\n", head->function_address, head->endpoint_number, virt_to_phys(tds), virt_to_phys(cur));
+	debug("doing bulk transfer with %x(%x). first_td at %x, last %x\n", head->config & ED_FUNC_MASK,
+		(head->config & ED_EP_MASK) >> ED_EP_SHIFT, virt_to_phys(tds), virt_to_phys(cur));
 
 	/* activate schedule */
 	OHCI_INST(ep->dev->controller)->opreg->HcBulkHeadED = virt_to_phys(head);
@@ -436,7 +427,7 @@ ohci_bulk (endpoint_t *ep, int dalen, u8 *data, int finalize)
 	int failure = wait_for_ed(ep->dev, head);
 	OHCI_INST(ep->dev->controller)->opreg->HcControl &= ~BulkListEnable;
 
-	ep->toggle = head->toggle;
+	ep->toggle = head->head_pointer & ED_TOGGLE;
 
 	/* free memory */
 	free((void*)tds);
diff --git a/payloads/libpayload/drivers/usb/ohci_private.h b/payloads/libpayload/drivers/usb/ohci_private.h
index a340be1f3a..d0b8ffcca9 100644
--- a/payloads/libpayload/drivers/usb/ohci_private.h
+++ b/payloads/libpayload/drivers/usb/ohci_private.h
@@ -206,49 +206,43 @@
 	typedef enum { OHCI_SETUP=0, OHCI_OUT=1, OHCI_IN=2, OHCI_FROM_TD=3 } ohci_pid_t;
 
 	typedef volatile struct {
-		union {
-			u32 dword0;
-			struct {
-				unsigned long function_address:7;
-				unsigned long endpoint_number:4;
-				unsigned long direction:2;
-				unsigned long lowspeed:1;
-				unsigned long skip:1;
-				unsigned long format:1;
-				unsigned long maximum_packet_size:11;
-				unsigned long:5;
-			} __attribute__ ((packed));
-		};
+		u32 config;
 		u32 tail_pointer;
-		union {
-			u32 head_pointer;
-			struct {
-				unsigned long halted:1;
-				unsigned long toggle:1;
-				unsigned long:30;
-			} __attribute__ ((packed));
-		};
+		u32 head_pointer;
 		u32 next_ed;
 	} __attribute__ ((packed)) ed_t;
+#define ED_HALTED 1
+#define ED_TOGGLE 2
+
+#define ED_FUNC_SHIFT 0
+#define ED_FUNC_MASK MASK(7, 0)
+#define ED_EP_SHIFT 7
+#define ED_EP_MASK MASK(4, 7)
+#define ED_DIR_SHIFT 11
+#define ED_DIR_MASK MASK(2, 11)
+#define ED_LOWSPEED (1 << 13)
+#define ED_MPS_SHIFT 16
 
 	typedef volatile struct {
-		union {
-			u32 dword0;
-			struct {
-				unsigned long:18;
-				unsigned long buffer_rounding:1;
-				unsigned long direction:2;
-				unsigned long delay_interrupt:3;
-				unsigned long toggle:1;
-				unsigned long toggle_from_td:1;
-				unsigned long error_count:2;
-				unsigned long condition_code:4;
-			} __attribute__ ((packed));
-		};
+		u32 config;
 		u32 current_buffer_pointer;
 		u32 next_td;
 		u32 buffer_end;
 	} __attribute__ ((packed)) td_t;
+#define TD_DIRECTION_SHIFT 19
+#define TD_DIRECTION_MASK MASK(2, TD_DIRECTION_SHIFT)
+#define TD_DIRECTION_SETUP OHCI_SETUP << TD_DIRECTION_SHIFT
+#define TD_DIRECTION_IN OHCI_IN << TD_DIRECTION_SHIFT
+#define TD_DIRECTION_OUT OHCI_OUT << TD_DIRECTION_SHIFT
+#define TD_DELAY_INTERRUPT_NODELAY (7 << 21)
+#define TD_TOGGLE_DATA0 0
+#define TD_TOGGLE_DATA1 (1 << 24)
+#define TD_TOGGLE_FROM_ED 0
+#define TD_TOGGLE_FROM_TD (1 << 25)
+#define TD_CC_SHIFT 28
+#define TD_CC_MASK MASK(4, TD_CC_SHIFT)
+#define TD_CC_NOERR 0
+#define TD_CC_NOACCESS (14 << TD_CC_SHIFT) /* the lower of the two values, so "no access" can be tested with >= */
 
 #define OHCI_INST(controller) ((ohci_t*)((controller)->instance))