Linux-2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
diff --git a/include/asm-i386/mca_dma.h b/include/asm-i386/mca_dma.h
new file mode 100644
index 0000000..4b3b526
--- /dev/null
+++ b/include/asm-i386/mca_dma.h
@@ -0,0 +1,202 @@
+#ifndef MCA_DMA_H
+#define MCA_DMA_H
+
+#include <asm/io.h>
+#include <linux/ioport.h>
+
+/*
+ * Microchannel specific DMA stuff.  DMA on an MCA machine is fairly similar to
+ *   standard PC dma, but it certainly has its quirks.  DMA register addresses
+ *   are in a different place and there are some added functions.  Most of this
+ *   should be pretty obvious on inspection.  Note that the user must divide
+ *   count by 2 when using 16-bit dma; that is not handled by these functions.
+ *
+ * Ramen Noodles are yummy.
+ * 
+ *  1998 Tymm Twillman <tymm@computer.org>  
+ */
+
+/*
+ * Registers that are used by the DMA controller; FN is the function register 
+ *   (tell the controller what to do) and EXE is the execution register (how
+ *   to do it)
+ */
+
+#define MCA_DMA_REG_FN  0x18
+#define MCA_DMA_REG_EXE 0x1A 
+
+/*
+ * Functions that the DMA controller can do
+ */
+
+#define MCA_DMA_FN_SET_IO       0x00
+#define MCA_DMA_FN_SET_ADDR     0x20
+#define MCA_DMA_FN_GET_ADDR     0x30
+#define MCA_DMA_FN_SET_COUNT    0x40
+#define MCA_DMA_FN_GET_COUNT    0x50
+#define MCA_DMA_FN_GET_STATUS   0x60
+#define MCA_DMA_FN_SET_MODE     0x70
+#define MCA_DMA_FN_SET_ARBUS    0x80
+#define MCA_DMA_FN_MASK         0x90
+#define MCA_DMA_FN_RESET_MASK   0xA0
+#define MCA_DMA_FN_MASTER_CLEAR 0xD0
+
+/*
+ * Modes (used by setting MCA_DMA_FN_MODE in the function register)
+ * 
+ * Note that the MODE_READ is read from memory (write to device), and
+ *   MODE_WRITE is vice-versa.  
+ */
+
+#define MCA_DMA_MODE_XFER  0x04  /* read by default */
+#define MCA_DMA_MODE_READ  0x04  /* same as XFER */
+#define MCA_DMA_MODE_WRITE 0x08  /* OR with MODE_XFER to use */
+#define MCA_DMA_MODE_IO    0x01  /* DMA from IO register */
+#define MCA_DMA_MODE_16    0x40  /* 16 bit xfers */
+
+
+/**
+ *	mca_enable_dma	-	channel to enable DMA on
+ *	@dmanr: DMA channel
+ *
+ *	Enable the MCA bus DMA on a channel. This can be called from
+ *	IRQ context.
+ */
+
+static __inline__ void mca_enable_dma(unsigned int dmanr)
+{
+	outb(MCA_DMA_FN_RESET_MASK | dmanr, MCA_DMA_REG_FN);
+}
+
+/**
+ *	mca_disble_dma	-	channel to disable DMA on
+ *	@dmanr: DMA channel
+ *
+ *	Enable the MCA bus DMA on a channel. This can be called from
+ *	IRQ context.
+ */
+
+static __inline__ void mca_disable_dma(unsigned int dmanr)
+{
+	outb(MCA_DMA_FN_MASK | dmanr, MCA_DMA_REG_FN);
+}
+
+/**
+ *	mca_set_dma_addr -	load a 24bit DMA address
+ *	@dmanr: DMA channel
+ *	@a: 24bit bus address
+ *
+ *	Load the address register in the DMA controller. This has a 24bit
+ *	limitation (16Mb). 
+ */
+
+static __inline__ void mca_set_dma_addr(unsigned int dmanr, unsigned int a)
+{
+	outb(MCA_DMA_FN_SET_ADDR | dmanr, MCA_DMA_REG_FN);
+	outb(a & 0xff, MCA_DMA_REG_EXE);
+	outb((a >> 8) & 0xff, MCA_DMA_REG_EXE);
+	outb((a >> 16) & 0xff, MCA_DMA_REG_EXE);
+}
+
+/**
+ *	mca_get_dma_addr -	load a 24bit DMA address
+ *	@dmanr: DMA channel
+ *
+ *	Read the address register in the DMA controller. This has a 24bit
+ *	limitation (16Mb). The return is a bus address.
+ */
+
+static __inline__ unsigned int mca_get_dma_addr(unsigned int dmanr)
+{
+	unsigned int addr;
+
+	outb(MCA_DMA_FN_GET_ADDR | dmanr, MCA_DMA_REG_FN);
+	addr = inb(MCA_DMA_REG_EXE);
+	addr |= inb(MCA_DMA_REG_EXE) << 8;
+	addr |= inb(MCA_DMA_REG_EXE) << 16;  
+
+	return addr;
+}
+
+/**
+ *	mca_set_dma_count -	load a 16bit transfer count
+ *	@dmanr: DMA channel
+ *	@count: count
+ *
+ *	Set the DMA count for this channel. This can be up to 64Kbytes.
+ *	Setting a count of zero will not do what you expect.
+ */
+
+static __inline__ void mca_set_dma_count(unsigned int dmanr, unsigned int count)
+{
+	count--;  /* transfers one more than count -- correct for this */
+
+	outb(MCA_DMA_FN_SET_COUNT | dmanr, MCA_DMA_REG_FN);
+	outb(count & 0xff, MCA_DMA_REG_EXE);
+	outb((count >> 8) & 0xff, MCA_DMA_REG_EXE);
+}
+
+/**
+ *	mca_get_dma_residue -	get the remaining bytes to transfer
+ *	@dmanr: DMA channel
+ *
+ *	This function returns the number of bytes left to transfer
+ *	on this DMA channel.
+ */
+
+static __inline__ unsigned int mca_get_dma_residue(unsigned int dmanr)
+{
+	unsigned short count;
+
+	outb(MCA_DMA_FN_GET_COUNT | dmanr, MCA_DMA_REG_FN);
+	count = 1 + inb(MCA_DMA_REG_EXE);
+	count += inb(MCA_DMA_REG_EXE) << 8;
+
+	return count;
+}
+
+/**
+ *	mca_set_dma_io -	set the port for an I/O transfer
+ *	@dmanr: DMA channel
+ *	@io_addr: an I/O port number
+ *
+ *	Unlike the ISA bus DMA controllers the DMA on MCA bus can transfer
+ *	with an I/O port target.
+ */
+
+static __inline__ void mca_set_dma_io(unsigned int dmanr, unsigned int io_addr)
+{
+	/*
+	 * DMA from a port address -- set the io address
+	 */
+	
+	outb(MCA_DMA_FN_SET_IO | dmanr, MCA_DMA_REG_FN);
+	outb(io_addr & 0xff, MCA_DMA_REG_EXE);
+	outb((io_addr >>  8) & 0xff, MCA_DMA_REG_EXE);
+}
+
+/**
+ *	mca_set_dma_mode -	set the DMA mode
+ *	@dmanr: DMA channel
+ *	@mode: mode to set
+ *
+ *	The DMA controller supports several modes. The mode values you can
+ *	set are :
+ *
+ *	%MCA_DMA_MODE_READ when reading from the DMA device.
+ *
+ *	%MCA_DMA_MODE_WRITE to writing to the DMA device.
+ *
+ *	%MCA_DMA_MODE_IO to do DMA to or from an I/O port.
+ *
+ *	%MCA_DMA_MODE_16 to do 16bit transfers.
+ *
+ */
+
+static __inline__ void mca_set_dma_mode(unsigned int dmanr, unsigned int mode)
+{
+	outb(MCA_DMA_FN_SET_MODE | dmanr, MCA_DMA_REG_FN);
+	outb(mode, MCA_DMA_REG_EXE);
+}
+
+#endif /* MCA_DMA_H */