USB: EHCI support for big-endian descriptors

This patch implements supports for EHCI controllers whose in-memory
data structures are represented in big-endian format. This is needed
(unfortunately) for the AMCC PPC440EPx SoC EHCI controller; the EHCI
spec doesn't specify little-endian format, although that's what most
other implementations use.

The guts of the patch are to introduce the hc32 type and change all
references from le32 to hc32.  All access routines are converted from
cpu_to_le32(...) to cpu_to_hc32(ehci, ...) and similar for the other
"direction".  (This is the same approach used with OHCI.)

David fixed:
	Whitespace fixes; refresh against ehci cpufreq patch; move glue
	for that PPC driver to the patch adding it; fix free symbol
	capture bugs in modified "constant" macros; and make "hc32" etc
	be "le32" unless we really need the BE options, so "sparse" can
	do some real good.

Signed-off-by: Stefan Roese <sr@denx.de>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 153 insertions, 52 deletions

diff --git a/drivers/usb/host/ehci.h b/drivers/usb/host/ehci.h
index a9ba5d28cdc2..79ad2af5ef6a 100644
--- a/drivers/usb/host/ehci.h
+++ b/drivers/usb/host/ehci.h
@@ -21,6 +21,22 @@
 
 /* definitions used for the EHCI driver */
 
+/*
+ * __hc32 and __hc16 are "Host Controller" types, they may be equivalent to
+ * __leXX (normally) or __beXX (given EHCI_BIG_ENDIAN_DESC), depending on
+ * the host controller implementation.
+ *
+ * To facilitate the strongest possible byte-order checking from "sparse"
+ * and so on, we use __leXX unless that's not practical.
+ */
+#ifdef CONFIG_USB_EHCI_BIG_ENDIAN_DESC
+typedef __u32 __bitwise __hc32;
+typedef __u16 __bitwise __hc16;
+#else
+#define __hc32	__le32
+#define __hc16	__le16
+#endif
+
 /* statistics can be kept for for tuning/monitoring */
 struct ehci_stats {
 	/* irq usage */
@@ -70,7 +86,7 @@ struct ehci_hcd {			/* one per controller */
 	/* periodic schedule support */
 #define	DEFAULT_I_TDPS		1024		/* some HCs can do less */
 	unsigned		periodic_size;
-	__le32			*periodic;	/* hw periodic table */
+	__hc32			*periodic;	/* hw periodic table */
 	dma_addr_t		periodic_dma;
 	unsigned		i_thresh;	/* uframes HC might cache */
 
@@ -103,6 +119,7 @@ struct ehci_hcd {			/* one per controller */
 	unsigned		no_selective_suspend:1;
 	unsigned		has_fsl_port_bug:1; /* FreeScale */
 	unsigned		big_endian_mmio:1;
+	unsigned		big_endian_desc:1;
 
 	u8			sbrn;		/* packed release number */
 
@@ -309,7 +326,7 @@ struct ehci_dbg_port {
 
 /*-------------------------------------------------------------------------*/
 
-#define	QTD_NEXT(dma)	cpu_to_le32((u32)dma)
+#define	QTD_NEXT(ehci, dma)	cpu_to_hc32(ehci, (u32)dma)
 
 /*
  * EHCI Specification 0.95 Section 3.5
@@ -321,9 +338,9 @@ struct ehci_dbg_port {
  */
 struct ehci_qtd {
 	/* first part defined by EHCI spec */
-	__le32			hw_next;	  /* see EHCI 3.5.1 */
-	__le32			hw_alt_next;      /* see EHCI 3.5.2 */
-	__le32			hw_token;         /* see EHCI 3.5.3 */
+	__hc32			hw_next;	/* see EHCI 3.5.1 */
+	__hc32			hw_alt_next;    /* see EHCI 3.5.2 */
+	__hc32			hw_token;       /* see EHCI 3.5.3 */
 #define	QTD_TOGGLE	(1 << 31)	/* data toggle */
 #define	QTD_LENGTH(tok)	(((tok)>>16) & 0x7fff)
 #define	QTD_IOC		(1 << 15)	/* interrupt on complete */
@@ -337,8 +354,13 @@ struct ehci_qtd {
 #define	QTD_STS_MMF	(1 << 2)	/* incomplete split transaction */
 #define	QTD_STS_STS	(1 << 1)	/* split transaction state */
 #define	QTD_STS_PING	(1 << 0)	/* issue PING? */
-	__le32			hw_buf [5];        /* see EHCI 3.5.4 */
-	__le32			hw_buf_hi [5];        /* Appendix B */
+
+#define ACTIVE_BIT(ehci)	cpu_to_hc32(ehci, QTD_STS_ACTIVE)
+#define HALT_BIT(ehci)		cpu_to_hc32(ehci, QTD_STS_HALT)
+#define STATUS_BIT(ehci)	cpu_to_hc32(ehci, QTD_STS_STS)
+
+	__hc32			hw_buf [5];        /* see EHCI 3.5.4 */
+	__hc32			hw_buf_hi [5];        /* Appendix B */
 
 	/* the rest is HCD-private */
 	dma_addr_t		qtd_dma;		/* qtd address */
@@ -348,26 +370,33 @@ struct ehci_qtd {
 } __attribute__ ((aligned (32)));
 
 /* mask NakCnt+T in qh->hw_alt_next */
-#define QTD_MASK __constant_cpu_to_le32 (~0x1f)
+#define QTD_MASK(ehci)	cpu_to_hc32 (ehci, ~0x1f)
 
 #define IS_SHORT_READ(token) (QTD_LENGTH (token) != 0 && QTD_PID (token) == 1)
 
 /*-------------------------------------------------------------------------*/
 
 /* type tag from {qh,itd,sitd,fstn}->hw_next */
-#define Q_NEXT_TYPE(dma) ((dma) & __constant_cpu_to_le32 (3 << 1))
+#define Q_NEXT_TYPE(ehci,dma)	((dma) & cpu_to_hc32(ehci, 3 << 1))
 
+/*
+ * Now the following defines are not converted using the
+ * __constant_cpu_to_le32() macro anymore, since we have to support
+ * "dynamic" switching between be and le support, so that the driver
+ * can be used on one system with SoC EHCI controller using big-endian
+ * descriptors as well as a normal little-endian PCI EHCI controller.
+ */
 /* values for that type tag */
-#define Q_TYPE_ITD	__constant_cpu_to_le32 (0 << 1)
-#define Q_TYPE_QH	__constant_cpu_to_le32 (1 << 1)
-#define Q_TYPE_SITD	__constant_cpu_to_le32 (2 << 1)
-#define Q_TYPE_FSTN	__constant_cpu_to_le32 (3 << 1)
+#define Q_TYPE_ITD	(0 << 1)
+#define Q_TYPE_QH	(1 << 1)
+#define Q_TYPE_SITD	(2 << 1)
+#define Q_TYPE_FSTN	(3 << 1)
 
 /* next async queue entry, or pointer to interrupt/periodic QH */
-#define	QH_NEXT(dma)	(cpu_to_le32(((u32)dma)&~0x01f)|Q_TYPE_QH)
+#define QH_NEXT(ehci,dma)	(cpu_to_hc32(ehci, (((u32)dma)&~0x01f)|Q_TYPE_QH))
 
 /* for periodic/async schedules and qtd lists, mark end of list */
-#define	EHCI_LIST_END	__constant_cpu_to_le32(1) /* "null pointer" to hw */
+#define EHCI_LIST_END(ehci)	cpu_to_hc32(ehci, 1) /* "null pointer" to hw */
 
 /*
  * Entries in periodic shadow table are pointers to one of four kinds
@@ -382,7 +411,7 @@ union ehci_shadow {
 	struct ehci_itd		*itd;		/* Q_TYPE_ITD */
 	struct ehci_sitd	*sitd;		/* Q_TYPE_SITD */
 	struct ehci_fstn	*fstn;		/* Q_TYPE_FSTN */
-	__le32			*hw_next;	/* (all types) */
+	__hc32			*hw_next;	/* (all types) */
 	void			*ptr;
 };
 
@@ -398,24 +427,27 @@ union ehci_shadow {
 
 struct ehci_qh {
 	/* first part defined by EHCI spec */
-	__le32			hw_next;	 /* see EHCI 3.6.1 */
-	__le32			hw_info1;        /* see EHCI 3.6.2 */
+	__hc32			hw_next;	/* see EHCI 3.6.1 */
+	__hc32			hw_info1;       /* see EHCI 3.6.2 */
 #define	QH_HEAD		0x00008000
 #define	QH_INACTIVATE	0x00000080
-	__le32			hw_info2;        /* see EHCI 3.6.2 */
+
+#define INACTIVATE_BIT(ehci)	cpu_to_hc32(ehci, QH_INACTIVATE)
+
+	__hc32			hw_info2;        /* see EHCI 3.6.2 */
 #define	QH_SMASK	0x000000ff
 #define	QH_CMASK	0x0000ff00
 #define	QH_HUBADDR	0x007f0000
 #define	QH_HUBPORT	0x3f800000
 #define	QH_MULT		0xc0000000
-	__le32			hw_current;	 /* qtd list - see EHCI 3.6.4 */
+	__hc32			hw_current;	/* qtd list - see EHCI 3.6.4 */
 
 	/* qtd overlay (hardware parts of a struct ehci_qtd) */
-	__le32			hw_qtd_next;
-	__le32			hw_alt_next;
-	__le32			hw_token;
-	__le32			hw_buf [5];
-	__le32			hw_buf_hi [5];
+	__hc32			hw_qtd_next;
+	__hc32			hw_alt_next;
+	__hc32			hw_token;
+	__hc32			hw_buf [5];
+	__hc32			hw_buf_hi [5];
 
 	/* the rest is HCD-private */
 	dma_addr_t		qh_dma;		/* address of qh */
@@ -456,7 +488,7 @@ struct ehci_qh {
 struct ehci_iso_packet {
 	/* These will be copied to iTD when scheduling */
 	u64			bufp;		/* itd->hw_bufp{,_hi}[pg] |= */
-	__le32			transaction;	/* itd->hw_transaction[i] |= */
+	__hc32			transaction;	/* itd->hw_transaction[i] |= */
 	u8			cross;		/* buf crosses pages */
 	/* for full speed OUT splits */
 	u32			buf1;
@@ -478,8 +510,8 @@ struct ehci_iso_sched {
  */
 struct ehci_iso_stream {
 	/* first two fields match QH, but info1 == 0 */
-	__le32			hw_next;
-	__le32			hw_info1;
+	__hc32			hw_next;
+	__hc32			hw_info1;
 
 	u32			refcount;
 	u8			bEndpointAddress;
@@ -494,7 +526,7 @@ struct ehci_iso_stream {
 	unsigned long		start;		/* jiffies */
 	unsigned long		rescheduled;
 	int			next_uframe;
-	__le32			splits;
+	__hc32			splits;
 
 	/* the rest is derived from the endpoint descriptor,
 	 * trusting urb->interval == f(epdesc->bInterval) and
@@ -508,12 +540,12 @@ struct ehci_iso_stream {
 	unsigned		bandwidth;
 
 	/* This is used to initialize iTD's hw_bufp fields */
-	__le32			buf0;
-	__le32			buf1;
-	__le32			buf2;
+	__hc32			buf0;
+	__hc32			buf1;
+	__hc32			buf2;
 
 	/* this is used to initialize sITD's tt info */
-	__le32			address;
+	__hc32			address;
 };
 
 /*-------------------------------------------------------------------------*/
@@ -526,8 +558,8 @@ struct ehci_iso_stream {
  */
 struct ehci_itd {
 	/* first part defined by EHCI spec */
-	__le32			hw_next;           /* see EHCI 3.3.1 */
-	__le32			hw_transaction [8]; /* see EHCI 3.3.2 */
+	__hc32			hw_next;           /* see EHCI 3.3.1 */
+	__hc32			hw_transaction [8]; /* see EHCI 3.3.2 */
 #define EHCI_ISOC_ACTIVE        (1<<31)        /* activate transfer this slot */
 #define EHCI_ISOC_BUF_ERR       (1<<30)        /* Data buffer error */
 #define EHCI_ISOC_BABBLE        (1<<29)        /* babble detected */
@@ -535,10 +567,10 @@ struct ehci_itd {
 #define	EHCI_ITD_LENGTH(tok)	(((tok)>>16) & 0x0fff)
 #define	EHCI_ITD_IOC		(1 << 15)	/* interrupt on complete */
 
-#define ITD_ACTIVE	__constant_cpu_to_le32(EHCI_ISOC_ACTIVE)
+#define ITD_ACTIVE(ehci)	cpu_to_hc32(ehci, EHCI_ISOC_ACTIVE)
 
-	__le32			hw_bufp [7];	/* see EHCI 3.3.3 */
-	__le32			hw_bufp_hi [7];	/* Appendix B */
+	__hc32			hw_bufp [7];	/* see EHCI 3.3.3 */
+	__hc32			hw_bufp_hi [7];	/* Appendix B */
 
 	/* the rest is HCD-private */
 	dma_addr_t		itd_dma;	/* for this itd */
@@ -565,11 +597,11 @@ struct ehci_itd {
  */
 struct ehci_sitd {
 	/* first part defined by EHCI spec */
-	__le32			hw_next;
+	__hc32			hw_next;
 /* uses bit field macros above - see EHCI 0.95 Table 3-8 */
-	__le32			hw_fullspeed_ep;	/* EHCI table 3-9 */
-	__le32			hw_uframe;		/* EHCI table 3-10 */
-	__le32			hw_results;		/* EHCI table 3-11 */
+	__hc32			hw_fullspeed_ep;	/* EHCI table 3-9 */
+	__hc32			hw_uframe;		/* EHCI table 3-10 */
+	__hc32			hw_results;		/* EHCI table 3-11 */
 #define	SITD_IOC	(1 << 31)	/* interrupt on completion */
 #define	SITD_PAGE	(1 << 30)	/* buffer 0/1 */
 #define	SITD_LENGTH(x)	(0x3ff & ((x)>>16))
@@ -581,11 +613,11 @@ struct ehci_sitd {
 #define	SITD_STS_MMF	(1 << 2)	/* incomplete split transaction */
 #define	SITD_STS_STS	(1 << 1)	/* split transaction state */
 
-#define SITD_ACTIVE	__constant_cpu_to_le32(SITD_STS_ACTIVE)
+#define SITD_ACTIVE(ehci)	cpu_to_hc32(ehci, SITD_STS_ACTIVE)
 
-	__le32			hw_buf [2];		/* EHCI table 3-12 */
-	__le32			hw_backpointer;		/* EHCI table 3-13 */
-	__le32			hw_buf_hi [2];		/* Appendix B */
+	__hc32			hw_buf [2];		/* EHCI table 3-12 */
+	__hc32			hw_backpointer;		/* EHCI table 3-13 */
+	__hc32			hw_buf_hi [2];		/* Appendix B */
 
 	/* the rest is HCD-private */
 	dma_addr_t		sitd_dma;
@@ -610,8 +642,8 @@ struct ehci_sitd {
  * it hits a "restore" FSTN; then it returns to finish other uframe 0/1 work.
  */
 struct ehci_fstn {
-	__le32			hw_next;	/* any periodic q entry */
-	__le32			hw_prev;	/* qh or EHCI_LIST_END */
+	__hc32			hw_next;	/* any periodic q entry */
+	__hc32			hw_prev;	/* qh or EHCI_LIST_END */
 
 	/* the rest is HCD-private */
 	dma_addr_t		fstn_dma;
@@ -683,8 +715,21 @@ ehci_port_speed(struct ehci_hcd *ehci, unsigned int portsc)
 #define ehci_big_endian_mmio(e)		0
 #endif
 
-static inline unsigned int ehci_readl (const struct ehci_hcd *ehci,
-				       __u32 __iomem * regs)
+/*
+ * Big-endian read/write functions are arch-specific.
+ * Other arches can be added if/when they're needed.
+ *
+ * REVISIT: arch/powerpc now has readl/writel_be, so the
+ * definition below can die once the 4xx support is
+ * finally ported over.
+ */
+#if defined(CONFIG_PPC)
+#define readl_be(addr)		in_be32((__force unsigned *)addr)
+#define writel_be(val, addr)	out_be32((__force unsigned *)addr, val)
+#endif
+
+static inline unsigned int ehci_readl(const struct ehci_hcd *ehci,
+		__u32 __iomem * regs)
 {
 #ifdef CONFIG_USB_EHCI_BIG_ENDIAN_MMIO
 	return ehci_big_endian_mmio(ehci) ?
@@ -695,8 +740,8 @@ static inline unsigned int ehci_readl (const struct ehci_hcd *ehci,
 #endif
 }
 
-static inline void ehci_writel (const struct ehci_hcd *ehci,
-				const unsigned int val, __u32 __iomem *regs)
+static inline void ehci_writel(const struct ehci_hcd *ehci,
+		const unsigned int val, __u32 __iomem *regs)
 {
 #ifdef CONFIG_USB_EHCI_BIG_ENDIAN_MMIO
 	ehci_big_endian_mmio(ehci) ?
@@ -709,6 +754,62 @@ static inline void ehci_writel (const struct ehci_hcd *ehci,
 
 /*-------------------------------------------------------------------------*/
 
+/*
+ * The AMCC 440EPx not only implements its EHCI registers in big-endian
+ * format, but also its DMA data structures (descriptors).
+ *
+ * EHCI controllers accessed through PCI work normally (little-endian
+ * everywhere), so we won't bother supporting a BE-only mode for now.
+ */
+#ifdef CONFIG_USB_EHCI_BIG_ENDIAN_DESC
+#define ehci_big_endian_desc(e)		((e)->big_endian_desc)
+
+/* cpu to ehci */
+static inline __hc32 cpu_to_hc32 (const struct ehci_hcd *ehci, const u32 x)
+{
+	return ehci_big_endian_desc(ehci)
+		? (__force __hc32)cpu_to_be32(x)
+		: (__force __hc32)cpu_to_le32(x);
+}
+
+/* ehci to cpu */
+static inline u32 hc32_to_cpu (const struct ehci_hcd *ehci, const __hc32 x)
+{
+	return ehci_big_endian_desc(ehci)
+		? be32_to_cpu((__force __be32)x)
+		: le32_to_cpu((__force __le32)x);
+}
+
+static inline u32 hc32_to_cpup (const struct ehci_hcd *ehci, const __hc32 *x)
+{
+	return ehci_big_endian_desc(ehci)
+		? be32_to_cpup((__force __be32 *)x)
+		: le32_to_cpup((__force __le32 *)x);
+}
+
+#else
+
+/* cpu to ehci */
+static inline __hc32 cpu_to_hc32 (const struct ehci_hcd *ehci, const u32 x)
+{
+	return cpu_to_le32(x);
+}
+
+/* ehci to cpu */
+static inline u32 hc32_to_cpu (const struct ehci_hcd *ehci, const __hc32 x)
+{
+	return le32_to_cpu(x);
+}
+
+static inline u32 hc32_to_cpup (const struct ehci_hcd *ehci, const __hc32 *x)
+{
+	return le32_to_cpup(x);
+}
+
+#endif
+
+/*-------------------------------------------------------------------------*/
+
 #ifndef DEBUG
 #define STUB_DEBUG_FILES
 #endif	/* DEBUG */