- Initialize the ifnet structure, especially if_dname, before probing

  the PHYs as some PHY drivers use it (but probably shouldn't). How
  gem(4) has worked with brgphy(4) on powerpc without this so far is
  unclear to me.
- Introduce a dying flag which is set during detach and checked in
  gem_ioctl() in order to prevent active BPF listeners to clear
  promiscuous mode which may lead to the tick callout being restarted
  which will trigger a panic once it's actually gone.
- In gem_stop() reset rather than just disable the transmitter and
  receiver in order to ensure we're not unloading DMA maps still in
  use by the hardware. [1]
- The blanking time is specified in PCI clocks so we should use twice
  the value when operating at 66MHz.
- Spell some 2 as ETHER_ALIGN and a 19 as GEM_STATUS_TX_COMPLETION_SHFT
  to make the actual intentions clear.
- As we don't unload the peak attempts counter ignore its overflow
  interrupts.
- Remove a stale setting of a variable to GEM_TD_INTERRUPT_ME which
  isn't used afterwards.
- For optimum performance increment the TX kick register in multiples
  of 4 if possible as suggested by the documentation.
- Partially revert r164931; drivers should only clear the watchdog
  timer if all outstanding TX descriptors are done.
- Fix some debugging strings.
- Add a missing BUS_DMASYNC_POSTWRITE in gem_rint().
- As the error paths in the interrupt handler are generally unlikely
  predict them as false.
- Add support for the SBus version of the GEM controller. [2]
- Add some lock assertions.
- Improve some comments.
- Fix some more or less cosmetic issues in the code of the PCI front-end.
- Change some softc members to be unsigned where more appropriate and
  remove unused ones.

Approved by:	re (kib)
Obtained from:	NetBSD (partially) [2], OpenBSD [1]
MFC after:	2 weeks

1 files changed, 24 insertions, 26 deletions

diff --git a/sys/dev/gem/if_gemvar.h b/sys/dev/gem/if_gemvar.h
index 76e2b20..48e3299 100644
--- a/sys/dev/gem/if_gemvar.h
+++ b/sys/dev/gem/if_gemvar.h
@@ -35,7 +35,7 @@
 #include <sys/callout.h>
 
 /*
- * Transmit descriptor list size.  This is arbitrary, but allocate
+ * Transmit descriptor ring size - this is arbitrary, but allocate
  * enough descriptors for 64 pending transmissions and 16 segments
  * per packet.  This limit is not actually enforced (packets with
  * more segments can be sent, depending on the busdma backend); it
@@ -50,7 +50,7 @@
 #define	GEM_NEXTTX(x)		((x + 1) & GEM_NTXDESC_MASK)
 
 /*
- * Receive descriptor list size.  We have one RX buffer per incoming
+ * Receive descriptor ring size - we have one RX buffer per incoming
  * packet, so this logic is a little simpler.
  */
 #define	GEM_NRXDESC		256
@@ -64,7 +64,7 @@
 #define	GEM_RXOWN_TICKS		(hz / 50)
 
 /*
- * Control structures are DMA'd to the GEM chip.  We allocate them
+ * Control structures are DMA'd to the chip.  We allocate them
  * in a single clump that maps to a single DMA segment to make
  * several things easier.
  */
@@ -83,9 +83,9 @@ struct gem_control_data {
 struct gem_txsoft {
 	struct mbuf *txs_mbuf;		/* head of our mbuf chain */
 	bus_dmamap_t txs_dmamap;	/* our DMA map */
-	int txs_firstdesc;		/* first descriptor in packet */
-	int txs_lastdesc;		/* last descriptor in packet */
-	int txs_ndescs;			/* number of descriptors */
+	u_int txs_firstdesc;		/* first descriptor in packet */
+	u_int txs_lastdesc;		/* last descriptor in packet */
+	u_int txs_ndescs;		/* number of descriptors */
 	STAILQ_ENTRY(gem_txsoft) txs_q;
 };
 
@@ -112,7 +112,7 @@ struct gem_softc {
 	u_char		sc_enaddr[ETHER_ADDR_LEN];
 	struct callout	sc_tick_ch;	/* tick callout */
 	struct callout	sc_rx_ch;	/* delayed RX callout */
-	int		sc_wdog_timer;	/* watchdog timer */
+	u_int		sc_wdog_timer;	/* watchdog timer */
 
 	void		*sc_ih;
 	struct resource *sc_res[3];
@@ -141,15 +141,15 @@ struct gem_softc {
 
 	u_int		sc_flags;
 #define	GEM_INITED	(1 << 0)	/* reset persistent regs init'ed */
-#define	GEM_LINK	(1 << 1)	/* link is up */
-#define	GEM_PCI		(1 << 2)	/* PCI busses are little-endian */
-#define	GEM_SERDES	(1 << 3)	/* use the SERDES */
+#define	GEM_DYING	(1 << 1)	/* detach initiated */
+#define	GEM_LINK	(1 << 2)	/* link is up */
+#define	GEM_PCI		(1 << 3)	/* PCI busses are little-endian */
+#define	GEM_PCI66	(1 << 4)	/* PCI bus runs at 66MHz */
+#define	GEM_SERDES	(1 << 5)	/* use the SERDES */
 
 	/*
 	 * ring buffer DMA stuff
 	 */
-	bus_dma_segment_t sc_cdseg;	/* control data memory */
-	int		sc_cdnseg;	/* number of segments */
 	bus_dmamap_t	sc_cddmamap;	/* control data DMA map */
 	bus_addr_t	sc_cddma;
 
@@ -166,18 +166,18 @@ struct gem_softc {
 #define	sc_txdescs	sc_control_data->gcd_txdescs
 #define	sc_rxdescs	sc_control_data->gcd_rxdescs
 
-	int		sc_txfree;	/* number of free TX descriptors */
-	int		sc_txnext;	/* next ready TX descriptor */
-	int		sc_txwin;	/* TX desc. since last TX intr. */
+	u_int		sc_txfree;	/* number of free TX descriptors */
+	u_int		sc_txnext;	/* next ready TX descriptor */
+	u_int		sc_txwin;	/* TX desc. since last TX intr. */
 
 	struct gem_txsq	sc_txfreeq;	/* free TX descsofts */
 	struct gem_txsq	sc_txdirtyq;	/* dirty TX descsofts */
 
-	int		sc_rxptr;	/* next ready RX desc./descsoft */
-	int		sc_rxfifosize;	/* RX FIFO size (bytes) */
+	u_int		sc_rxptr;	/* next ready RX descriptor/state */
+	u_int		sc_rxfifosize;	/* RX FIFO size (bytes) */
 
 	int		sc_ifflags;
-	int		sc_csum_features;
+	u_long		sc_csum_features;
 };
 
 #define	GEM_BANKN_BARRIER(n, sc, offs, len, flags)			\
@@ -238,10 +238,9 @@ do {									\
 	__m->m_data = __m->m_ext.ext_buf;				\
 	__rxd->gd_addr =						\
 	    GEM_DMA_WRITE((sc), __rxs->rxs_paddr);			\
-	__rxd->gd_flags =						\
-	    GEM_DMA_WRITE((sc),						\
-			(((__m->m_ext.ext_size) << GEM_RD_BUFSHIFT)	\
-				& GEM_RD_BUFSIZE) | GEM_RD_OWN);	\
+	__rxd->gd_flags = GEM_DMA_WRITE((sc),				\
+	    (((__m->m_ext.ext_size) << GEM_RD_BUFSHIFT)	&		\
+	    GEM_RD_BUFSIZE) | GEM_RD_OWN);				\
 } while (0)
 
 #define	GEM_UPDATE_RXDESC(sc, x)					\
@@ -250,10 +249,9 @@ do {									\
 	struct gem_desc *__rxd = &sc->sc_rxdescs[(x)];			\
 	struct mbuf *__m = __rxs->rxs_mbuf;				\
 									\
-	__rxd->gd_flags =						\
-	    GEM_DMA_WRITE((sc),						\
-			(((__m->m_ext.ext_size) << GEM_RD_BUFSHIFT)	\
-				& GEM_RD_BUFSIZE) | GEM_RD_OWN);	\
+	__rxd->gd_flags = GEM_DMA_WRITE((sc),				\
+	    (((__m->m_ext.ext_size) << GEM_RD_BUFSHIFT)	&		\
+	    GEM_RD_BUFSIZE) | GEM_RD_OWN);				\
 } while (0)
 
 #define	GEM_LOCK_INIT(_sc, _name)					\