Merge branch 'legacy-isa-delete' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux

Paul Gortmaker says:

====================
The Ethernet-HowTo was maintained for roughly 10 years, from 1993 to 2003.
Fortunately sane hardware probing and auto detection (via PCI and ISA/PnP)
largely made the document a relic of the past, hence it being abandoned
a decade ago.

However, there is one last useful thing that we can extract from the
effort made in maintaining that document.  We can use it to guide us
with respect to what rare, experimental and/or super ancient 10Mbit
ISA drivers don't make sense to maintain in-tree anymore.

Nobody will argue that ISA is obsolete.  Availability went away at about
the time Pentium3 motherboards moved from 500MHz Slot1/SECC processors
to the green 500MHz Socket 370 Pentium3 chips, at the turn of the century.

In theory, it is possible that someone could still be running one of these
12+ year old P3 machines and want 3.9+ bleeding edge kernels (but unlikely).
In light of the above (remote) possibility, we can defer the removal of some
ISA network drivers that were highly popular and well tested.  Typically
that means the stuff more from the mid to late '90s, some with ISA PnP
support, like the 3c509, the wd/SMC 8390 based stuff, PCnet/lance etc.

But a lot of other drivers, typically from the early 1990s were for rare
hardware, and experimental (to the point of requiring a cron job that would
do a test ping, and then ifconfig down/up and/or a rmmod/insmod!).  And
some of these drivers (znet, and lp486e to name two) are physically tied
to platforms with on motherboard ethernet -- of 486 machines that date
from the early 1990s and can only have single digit amounts of memory.

What I'd like to achieve here with this series, is to get rid of those old
drivers that are no longer being used.  In an earlier discussion where
I'd proposed deleting a single driver, Alan suggested we instead dump
all the historical stuff in one go, to make it "...immediately obvious
where the break point is..."[1] and that it was "perfectly reasonable it
(and a pile of other ISA cards) ought to be shown the door"[2].  So that
is the goal here - make a clear line in the sand where the really ancient
stuff finally gets kicked to the curb.

Two old parallel port drivers are considered for removal here as well,
since in early 386/486 ISA machines, the parallel port was typically found
with the UARTS on the multi-I/O ISA controller card.  These drivers also date
from the early 1990's; parallel ports are no longer found on modern boards,
and their performance was not even capable of 10% of 10Mbit bandwidth.

Allow me a preemptive justification against the inevitable comments from
well meaning bystanders who suggest "why not just leave all this alone?".
Dead drivers cost us all if they are left in tree.  If you think that
is false, then please first consider:

-every time you type "git status", you are checking to see if modifications
 have been made by you to all that dead code.

-every time you type "git grep <regex>" you are searching through files
 which contain that dead code that simply does not interest you.

-every time you build a "allyesconfig" and an "allmodconfig" (don't tell
 me you skip this step before submitting your changes to a maintainer),
 you waste CPU cycles building this dead code.

-every time there is a tree wide API change, or cleanup, or file relocation,
 we pay the cost of updating dead code, or moving dead code.

-daily regression tests (take linux-next as the most transparent
 example) spend time building (and possibly running) this dead code.

-hard working people who regularly run auditing tools looking for lurking
 bugs (sparse/coverity/smatch/coccinelle) are wasting time checking for,
 and fixing bugs in this dead code.

This last one is key.  Please take a look at the git history for the
files that are proposed for removal here.  Look at the git history for
any one of them ("git whatchanged --follow drivers/net/.../driver.c")
Mentally sort the changes into two bins -- (1) the robotic tree-wide
changes, and (2) the "look I found a real run-time bug while using this"
category.  You will see that category #2 is essentially empty.

Further to that, realize that drivers don't simply disappear.  We are
not operating in the binary-only distribution space like other OS.  All
these drivers remain in the git history forever.  If a person is an
enthusiast for extreme legacy hardware, they are probably already
customizing their kernel source and building it themselves to support
such systems.  Also keep in mind that they could still build the 3.8
kernel exactly as-is, and run it (or a 3.8.x stable variant of it) for
several more years if they were really determined to cling to these old
experimental ISA drivers for some reason.

In summary, I hope that folks can be pragmatic about this, and not
get swept up in nostalgia.  Ask yourself whether it is realistic to
expect a person would have a genuine use case where they would
need to build a 3.9+ modern kernel and install it on some legacy hardware
that has no option but to absolutely _require_ one of the drivers
that are deleted here.

The following series was created with --irreversible-delete for
ease of review (it skips showing the content of files that are
deleted); however the complete patches can be pulled as per below.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 0 insertions, 292 deletions

diff --git a/drivers/net/ethernet/i825xx/3c505.h b/drivers/net/ethernet/i825xx/3c505.h
deleted file mode 100644
index 04df2a9..0000000
--- a/drivers/net/ethernet/i825xx/3c505.h
+++ /dev/null
@@ -1,292 +0,0 @@
-/*****************************************************************
- *
- *  defines for 3Com Etherlink Plus adapter
- *
- *****************************************************************/
-
-#define ELP_DMA       6
-#define ELP_RX_PCBS   4
-#define ELP_MAX_CARDS 4
-
-/*
- * I/O register offsets
- */
-#define	PORT_COMMAND	0x00	/* read/write, 8-bit */
-#define	PORT_STATUS	0x02	/* read only, 8-bit */
-#define	PORT_AUXDMA	0x02	/* write only, 8-bit */
-#define	PORT_DATA	0x04	/* read/write, 16-bit */
-#define	PORT_CONTROL	0x06	/* read/write, 8-bit */
-
-#define ELP_IO_EXTENT	0x10	/* size of used IO registers */
-
-/*
- * host control registers bits
- */
-#define	ATTN	0x80	/* attention */
-#define	FLSH	0x40	/* flush data register */
-#define DMAE	0x20	/* DMA enable */
-#define DIR	0x10	/* direction */
-#define	TCEN	0x08	/* terminal count interrupt enable */
-#define	CMDE	0x04	/* command register interrupt enable */
-#define	HSF2	0x02	/* host status flag 2 */
-#define	HSF1	0x01	/* host status flag 1 */
-
-/*
- * combinations of HSF flags used for PCB transmission
- */
-#define	HSF_PCB_ACK	HSF1
-#define	HSF_PCB_NAK	HSF2
-#define	HSF_PCB_END	(HSF2|HSF1)
-#define	HSF_PCB_MASK	(HSF2|HSF1)
-
-/*
- * host status register bits
- */
-#define	HRDY	0x80	/* data register ready */
-#define	HCRE	0x40	/* command register empty */
-#define	ACRF	0x20	/* adapter command register full */
-/* #define DIR 	0x10	direction - same as in control register */
-#define	DONE	0x08	/* DMA done */
-#define	ASF3	0x04	/* adapter status flag 3 */
-#define	ASF2	0x02	/* adapter status flag 2 */
-#define	ASF1	0x01	/* adapter status flag 1 */
-
-/*
- * combinations of ASF flags used for PCB reception
- */
-#define	ASF_PCB_ACK	ASF1
-#define	ASF_PCB_NAK	ASF2
-#define	ASF_PCB_END	(ASF2|ASF1)
-#define	ASF_PCB_MASK	(ASF2|ASF1)
-
-/*
- * host aux DMA register bits
- */
-#define	DMA_BRST	0x01	/* DMA burst */
-
-/*
- * maximum amount of data allowed in a PCB
- */
-#define	MAX_PCB_DATA	62
-
-/*****************************************************************
- *
- *  timeout value
- *	this is a rough value used for loops to stop them from
- *	locking up the whole machine in the case of failure or
- *	error conditions
- *
- *****************************************************************/
-
-#define	TIMEOUT	300
-
-/*****************************************************************
- *
- * PCB commands
- *
- *****************************************************************/
-
-enum {
-  /*
-   * host PCB commands
-   */
-  CMD_CONFIGURE_ADAPTER_MEMORY	= 0x01,
-  CMD_CONFIGURE_82586		= 0x02,
-  CMD_STATION_ADDRESS		= 0x03,
-  CMD_DMA_DOWNLOAD		= 0x04,
-  CMD_DMA_UPLOAD		= 0x05,
-  CMD_PIO_DOWNLOAD		= 0x06,
-  CMD_PIO_UPLOAD		= 0x07,
-  CMD_RECEIVE_PACKET		= 0x08,
-  CMD_TRANSMIT_PACKET		= 0x09,
-  CMD_NETWORK_STATISTICS	= 0x0a,
-  CMD_LOAD_MULTICAST_LIST	= 0x0b,
-  CMD_CLEAR_PROGRAM		= 0x0c,
-  CMD_DOWNLOAD_PROGRAM		= 0x0d,
-  CMD_EXECUTE_PROGRAM		= 0x0e,
-  CMD_SELF_TEST			= 0x0f,
-  CMD_SET_STATION_ADDRESS	= 0x10,
-  CMD_ADAPTER_INFO		= 0x11,
-  NUM_TRANSMIT_CMDS,
-
-  /*
-   * adapter PCB commands
-   */
-  CMD_CONFIGURE_ADAPTER_RESPONSE	= 0x31,
-  CMD_CONFIGURE_82586_RESPONSE		= 0x32,
-  CMD_ADDRESS_RESPONSE			= 0x33,
-  CMD_DOWNLOAD_DATA_REQUEST		= 0x34,
-  CMD_UPLOAD_DATA_REQUEST		= 0x35,
-  CMD_RECEIVE_PACKET_COMPLETE		= 0x38,
-  CMD_TRANSMIT_PACKET_COMPLETE		= 0x39,
-  CMD_NETWORK_STATISTICS_RESPONSE	= 0x3a,
-  CMD_LOAD_MULTICAST_RESPONSE		= 0x3b,
-  CMD_CLEAR_PROGRAM_RESPONSE		= 0x3c,
-  CMD_DOWNLOAD_PROGRAM_RESPONSE		= 0x3d,
-  CMD_EXECUTE_RESPONSE			= 0x3e,
-  CMD_SELF_TEST_RESPONSE		= 0x3f,
-  CMD_SET_ADDRESS_RESPONSE		= 0x40,
-  CMD_ADAPTER_INFO_RESPONSE		= 0x41
-};
-
-/* Definitions for the PCB data structure */
-
-/* Data units */
-typedef unsigned char         byte;
-typedef unsigned short int    word;
-typedef unsigned long int     dword;
-
-/* Data structures */
-struct Memconf {
-	word	cmd_q,
-		rcv_q,
-		mcast,
-		frame,
-		rcv_b,
-		progs;
-};
-
-struct Rcv_pkt {
-	word	buf_ofs,
-		buf_seg,
-		buf_len,
-		timeout;
-};
-
-struct Xmit_pkt {
-	word	buf_ofs,
-		buf_seg,
-		pkt_len;
-};
-
-struct Rcv_resp {
-	word	buf_ofs,
-		buf_seg,
-		buf_len,
-		pkt_len,
-		timeout,
-		status;
-	dword	timetag;
-};
-
-struct Xmit_resp {
-	word	buf_ofs,
-		buf_seg,
-		c_stat,
-		status;
-};
-
-
-struct Netstat {
-	dword	tot_recv,
-		tot_xmit;
-	word	err_CRC,
-		err_align,
-		err_res,
-		err_ovrrun;
-};
-
-
-struct Selftest {
-	word	error;
-	union {
-		word ROM_cksum;
-		struct {
-			word ofs, seg;
-		} RAM;
-		word i82586;
-	} failure;
-};
-
-struct Info {
-	byte	minor_vers,
-		major_vers;
-	word	ROM_cksum,
-		RAM_sz,
-		free_ofs,
-		free_seg;
-};
-
-struct Memdump {
-       word size,
-            off,
-            seg;
-};
-
-/*
-Primary Command Block. The most important data structure. All communication
-between the host and the adapter is done with these. (Except for the actual
-Ethernet data, which has different packaging.)
-*/
-typedef struct {
-	byte	command;
-	byte	length;
-	union	{
-		struct Memconf		memconf;
-		word			configure;
-		struct Rcv_pkt		rcv_pkt;
-		struct Xmit_pkt		xmit_pkt;
-		byte			multicast[10][6];
-		byte			eth_addr[6];
-		byte			failed;
-		struct Rcv_resp		rcv_resp;
-		struct Xmit_resp	xmit_resp;
-		struct Netstat		netstat;
-		struct Selftest		selftest;
-		struct Info		info;
-		struct Memdump    	memdump;
-		byte			raw[62];
-	} data;
-} pcb_struct;
-
-/* These defines for 'configure' */
-#define RECV_STATION	0x00
-#define RECV_BROAD	0x01
-#define RECV_MULTI	0x02
-#define RECV_PROMISC	0x04
-#define NO_LOOPBACK	0x00
-#define INT_LOOPBACK	0x08
-#define EXT_LOOPBACK	0x10
-
-/*****************************************************************
- *
- *  structure to hold context information for adapter
- *
- *****************************************************************/
-
-#define DMA_BUFFER_SIZE  1600
-#define BACKLOG_SIZE      4
-
-typedef struct {
-	volatile short got[NUM_TRANSMIT_CMDS];	/* flags for
-						   command completion */
-	pcb_struct tx_pcb;	/* PCB for foreground sending */
-	pcb_struct rx_pcb;	/* PCB for foreground receiving */
-	pcb_struct itx_pcb;	/* PCB for background sending */
-	pcb_struct irx_pcb;	/* PCB for background receiving */
-
-	void *dma_buffer;
-
-	struct {
-		unsigned int length[BACKLOG_SIZE];
-		unsigned int in;
-		unsigned int out;
-	} rx_backlog;
-
-	struct {
-		unsigned int direction;
-		unsigned int length;
-		struct sk_buff *skb;
-	        void *target;
-		unsigned long start_time;
-	} current_dma;
-
-	/* flags */
-	unsigned long send_pcb_semaphore;
-	unsigned long dmaing;
-	unsigned long busy;
-
-	unsigned int rx_active;  /* number of receive PCBs */
-        volatile unsigned char hcr_val;  /* what we think the HCR contains */
-        spinlock_t lock;	/* Interrupt v tx lock */
-} elp_device;