tty: move drivers/serial/ to drivers/tty/serial/

The serial drivers are really just tty drivers, so move them to
drivers/tty/ to make things a bit neater overall.

This is part of the tty/serial driver movement proceedure as proposed by
Arnd Bergmann and approved by everyone involved a number of months ago.

Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Rogier Wolff <R.E.Wolff@bitwizard.nl>
Cc: Michael H. Warfield <mhw@wittsend.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 2159 insertions, 0 deletions

diff --git a/drivers/tty/serial/mpsc.c b/drivers/tty/serial/mpsc.c
new file mode 100644
index 00000000000..6a9c6605666
--- /dev/null
+++ b/drivers/tty/serial/mpsc.c
@@ -0,0 +1,2159 @@
+/*
+ * Generic driver for the MPSC (UART mode) on Marvell parts (e.g., GT64240,
+ * GT64260, MV64340, MV64360, GT96100, ... ).
+ *
+ * Author: Mark A. Greer <mgreer@mvista.com>
+ *
+ * Based on an old MPSC driver that was in the linuxppc tree.  It appears to
+ * have been created by Chris Zankel (formerly of MontaVista) but there
+ * is no proper Copyright so I'm not sure.  Apparently, parts were also
+ * taken from PPCBoot (now U-Boot).  Also based on drivers/serial/8250.c
+ * by Russell King.
+ *
+ * 2004 (c) MontaVista, Software, Inc.  This file is licensed under
+ * the terms of the GNU General Public License version 2.  This program
+ * is licensed "as is" without any warranty of any kind, whether express
+ * or implied.
+ */
+/*
+ * The MPSC interface is much like a typical network controller's interface.
+ * That is, you set up separate rings of descriptors for transmitting and
+ * receiving data.  There is also a pool of buffers with (one buffer per
+ * descriptor) that incoming data are dma'd into or outgoing data are dma'd
+ * out of.
+ *
+ * The MPSC requires two other controllers to be able to work.  The Baud Rate
+ * Generator (BRG) provides a clock at programmable frequencies which determines
+ * the baud rate.  The Serial DMA Controller (SDMA) takes incoming data from the
+ * MPSC and DMA's it into memory or DMA's outgoing data and passes it to the
+ * MPSC.  It is actually the SDMA interrupt that the driver uses to keep the
+ * transmit and receive "engines" going (i.e., indicate data has been
+ * transmitted or received).
+ *
+ * NOTES:
+ *
+ * 1) Some chips have an erratum where several regs cannot be
+ * read.  To work around that, we keep a local copy of those regs in
+ * 'mpsc_port_info'.
+ *
+ * 2) Some chips have an erratum where the ctlr will hang when the SDMA ctlr
+ * accesses system mem with coherency enabled.  For that reason, the driver
+ * assumes that coherency for that ctlr has been disabled.  This means
+ * that when in a cache coherent system, the driver has to manually manage
+ * the data cache on the areas that it touches because the dma_* macro are
+ * basically no-ops.
+ *
+ * 3) There is an erratum (on PPC) where you can't use the instruction to do
+ * a DMA_TO_DEVICE/cache clean so DMA_BIDIRECTIONAL/flushes are used in places
+ * where a DMA_TO_DEVICE/clean would have [otherwise] sufficed.
+ *
+ * 4) AFAICT, hardware flow control isn't supported by the controller --MAG.
+ */
+
+
+#if defined(CONFIG_SERIAL_MPSC_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
+#define SUPPORT_SYSRQ
+#endif
+
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/tty.h>
+#include <linux/tty_flip.h>
+#include <linux/ioport.h>
+#include <linux/init.h>
+#include <linux/console.h>
+#include <linux/sysrq.h>
+#include <linux/serial.h>
+#include <linux/serial_core.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/dma-mapping.h>
+#include <linux/mv643xx.h>
+#include <linux/platform_device.h>
+#include <linux/gfp.h>
+
+#include <asm/io.h>
+#include <asm/irq.h>
+
+#define	MPSC_NUM_CTLRS		2
+
+/*
+ * Descriptors and buffers must be cache line aligned.
+ * Buffers lengths must be multiple of cache line size.
+ * Number of Tx & Rx descriptors must be powers of 2.
+ */
+#define	MPSC_RXR_ENTRIES	32
+#define	MPSC_RXRE_SIZE		dma_get_cache_alignment()
+#define	MPSC_RXR_SIZE		(MPSC_RXR_ENTRIES * MPSC_RXRE_SIZE)
+#define	MPSC_RXBE_SIZE		dma_get_cache_alignment()
+#define	MPSC_RXB_SIZE		(MPSC_RXR_ENTRIES * MPSC_RXBE_SIZE)
+
+#define	MPSC_TXR_ENTRIES	32
+#define	MPSC_TXRE_SIZE		dma_get_cache_alignment()
+#define	MPSC_TXR_SIZE		(MPSC_TXR_ENTRIES * MPSC_TXRE_SIZE)
+#define	MPSC_TXBE_SIZE		dma_get_cache_alignment()
+#define	MPSC_TXB_SIZE		(MPSC_TXR_ENTRIES * MPSC_TXBE_SIZE)
+
+#define	MPSC_DMA_ALLOC_SIZE	(MPSC_RXR_SIZE + MPSC_RXB_SIZE + MPSC_TXR_SIZE \
+		+ MPSC_TXB_SIZE + dma_get_cache_alignment() /* for alignment */)
+
+/* Rx and Tx Ring entry descriptors -- assume entry size is <= cacheline size */
+struct mpsc_rx_desc {
+	u16 bufsize;
+	u16 bytecnt;
+	u32 cmdstat;
+	u32 link;
+	u32 buf_ptr;
+} __attribute((packed));
+
+struct mpsc_tx_desc {
+	u16 bytecnt;
+	u16 shadow;
+	u32 cmdstat;
+	u32 link;
+	u32 buf_ptr;
+} __attribute((packed));
+
+/*
+ * Some regs that have the erratum that you can't read them are are shared
+ * between the two MPSC controllers.  This struct contains those shared regs.
+ */
+struct mpsc_shared_regs {
+	phys_addr_t mpsc_routing_base_p;
+	phys_addr_t sdma_intr_base_p;
+
+	void __iomem *mpsc_routing_base;
+	void __iomem *sdma_intr_base;
+
+	u32 MPSC_MRR_m;
+	u32 MPSC_RCRR_m;
+	u32 MPSC_TCRR_m;
+	u32 SDMA_INTR_CAUSE_m;
+	u32 SDMA_INTR_MASK_m;
+};
+
+/* The main driver data structure */
+struct mpsc_port_info {
+	struct uart_port port;	/* Overlay uart_port structure */
+
+	/* Internal driver state for this ctlr */
+	u8 ready;
+	u8 rcv_data;
+	tcflag_t c_iflag;	/* save termios->c_iflag */
+	tcflag_t c_cflag;	/* save termios->c_cflag */
+
+	/* Info passed in from platform */
+	u8 mirror_regs;		/* Need to mirror regs? */
+	u8 cache_mgmt;		/* Need manual cache mgmt? */
+	u8 brg_can_tune;	/* BRG has baud tuning? */
+	u32 brg_clk_src;
+	u16 mpsc_max_idle;
+	int default_baud;
+	int default_bits;
+	int default_parity;
+	int default_flow;
+
+	/* Physical addresses of various blocks of registers (from platform) */
+	phys_addr_t mpsc_base_p;
+	phys_addr_t sdma_base_p;
+	phys_addr_t brg_base_p;
+
+	/* Virtual addresses of various blocks of registers (from platform) */
+	void __iomem *mpsc_base;
+	void __iomem *sdma_base;
+	void __iomem *brg_base;
+
+	/* Descriptor ring and buffer allocations */
+	void *dma_region;
+	dma_addr_t dma_region_p;
+
+	dma_addr_t rxr;		/* Rx descriptor ring */
+	dma_addr_t rxr_p;	/* Phys addr of rxr */
+	u8 *rxb;		/* Rx Ring I/O buf */
+	u8 *rxb_p;		/* Phys addr of rxb */
+	u32 rxr_posn;		/* First desc w/ Rx data */
+
+	dma_addr_t txr;		/* Tx descriptor ring */
+	dma_addr_t txr_p;	/* Phys addr of txr */
+	u8 *txb;		/* Tx Ring I/O buf */
+	u8 *txb_p;		/* Phys addr of txb */
+	int txr_head;		/* Where new data goes */
+	int txr_tail;		/* Where sent data comes off */
+	spinlock_t tx_lock;	/* transmit lock */
+
+	/* Mirrored values of regs we can't read (if 'mirror_regs' set) */
+	u32 MPSC_MPCR_m;
+	u32 MPSC_CHR_1_m;
+	u32 MPSC_CHR_2_m;
+	u32 MPSC_CHR_10_m;
+	u32 BRG_BCR_m;
+	struct mpsc_shared_regs *shared_regs;
+};
+
+/* Hooks to platform-specific code */
+int mpsc_platform_register_driver(void);
+void mpsc_platform_unregister_driver(void);
+
+/* Hooks back in to mpsc common to be called by platform-specific code */
+struct mpsc_port_info *mpsc_device_probe(int index);
+struct mpsc_port_info *mpsc_device_remove(int index);
+
+/* Main MPSC Configuration Register Offsets */
+#define	MPSC_MMCRL			0x0000
+#define	MPSC_MMCRH			0x0004
+#define	MPSC_MPCR			0x0008
+#define	MPSC_CHR_1			0x000c
+#define	MPSC_CHR_2			0x0010
+#define	MPSC_CHR_3			0x0014
+#define	MPSC_CHR_4			0x0018
+#define	MPSC_CHR_5			0x001c
+#define	MPSC_CHR_6			0x0020
+#define	MPSC_CHR_7			0x0024
+#define	MPSC_CHR_8			0x0028
+#define	MPSC_CHR_9			0x002c
+#define	MPSC_CHR_10			0x0030
+#define	MPSC_CHR_11			0x0034
+
+#define	MPSC_MPCR_FRZ			(1 << 9)
+#define	MPSC_MPCR_CL_5			0
+#define	MPSC_MPCR_CL_6			1
+#define	MPSC_MPCR_CL_7			2
+#define	MPSC_MPCR_CL_8			3
+#define	MPSC_MPCR_SBL_1			0
+#define	MPSC_MPCR_SBL_2			1
+
+#define	MPSC_CHR_2_TEV			(1<<1)
+#define	MPSC_CHR_2_TA			(1<<7)
+#define	MPSC_CHR_2_TTCS			(1<<9)
+#define	MPSC_CHR_2_REV			(1<<17)
+#define	MPSC_CHR_2_RA			(1<<23)
+#define	MPSC_CHR_2_CRD			(1<<25)
+#define	MPSC_CHR_2_EH			(1<<31)
+#define	MPSC_CHR_2_PAR_ODD		0
+#define	MPSC_CHR_2_PAR_SPACE		1
+#define	MPSC_CHR_2_PAR_EVEN		2
+#define	MPSC_CHR_2_PAR_MARK		3
+
+/* MPSC Signal Routing */
+#define	MPSC_MRR			0x0000
+#define	MPSC_RCRR			0x0004
+#define	MPSC_TCRR			0x0008
+
+/* Serial DMA Controller Interface Registers */
+#define	SDMA_SDC			0x0000
+#define	SDMA_SDCM			0x0008
+#define	SDMA_RX_DESC			0x0800
+#define	SDMA_RX_BUF_PTR			0x0808
+#define	SDMA_SCRDP			0x0810
+#define	SDMA_TX_DESC			0x0c00
+#define	SDMA_SCTDP			0x0c10
+#define	SDMA_SFTDP			0x0c14
+
+#define	SDMA_DESC_CMDSTAT_PE		(1<<0)
+#define	SDMA_DESC_CMDSTAT_CDL		(1<<1)
+#define	SDMA_DESC_CMDSTAT_FR		(1<<3)
+#define	SDMA_DESC_CMDSTAT_OR		(1<<6)
+#define	SDMA_DESC_CMDSTAT_BR		(1<<9)
+#define	SDMA_DESC_CMDSTAT_MI		(1<<10)
+#define	SDMA_DESC_CMDSTAT_A		(1<<11)
+#define	SDMA_DESC_CMDSTAT_AM		(1<<12)
+#define	SDMA_DESC_CMDSTAT_CT		(1<<13)
+#define	SDMA_DESC_CMDSTAT_C		(1<<14)
+#define	SDMA_DESC_CMDSTAT_ES		(1<<15)
+#define	SDMA_DESC_CMDSTAT_L		(1<<16)
+#define	SDMA_DESC_CMDSTAT_F		(1<<17)
+#define	SDMA_DESC_CMDSTAT_P		(1<<18)
+#define	SDMA_DESC_CMDSTAT_EI		(1<<23)
+#define	SDMA_DESC_CMDSTAT_O		(1<<31)
+
+#define SDMA_DESC_DFLT			(SDMA_DESC_CMDSTAT_O \
+		| SDMA_DESC_CMDSTAT_EI)
+
+#define	SDMA_SDC_RFT			(1<<0)
+#define	SDMA_SDC_SFM			(1<<1)
+#define	SDMA_SDC_BLMR			(1<<6)
+#define	SDMA_SDC_BLMT			(1<<7)
+#define	SDMA_SDC_POVR			(1<<8)
+#define	SDMA_SDC_RIFB			(1<<9)
+
+#define	SDMA_SDCM_ERD			(1<<7)
+#define	SDMA_SDCM_AR			(1<<15)
+#define	SDMA_SDCM_STD			(1<<16)
+#define	SDMA_SDCM_TXD			(1<<23)
+#define	SDMA_SDCM_AT			(1<<31)
+
+#define	SDMA_0_CAUSE_RXBUF		(1<<0)
+#define	SDMA_0_CAUSE_RXERR		(1<<1)
+#define	SDMA_0_CAUSE_TXBUF		(1<<2)
+#define	SDMA_0_CAUSE_TXEND		(1<<3)
+#define	SDMA_1_CAUSE_RXBUF		(1<<8)
+#define	SDMA_1_CAUSE_RXERR		(1<<9)
+#define	SDMA_1_CAUSE_TXBUF		(1<<10)
+#define	SDMA_1_CAUSE_TXEND		(1<<11)
+
+#define	SDMA_CAUSE_RX_MASK	(SDMA_0_CAUSE_RXBUF | SDMA_0_CAUSE_RXERR \
+		| SDMA_1_CAUSE_RXBUF | SDMA_1_CAUSE_RXERR)
+#define	SDMA_CAUSE_TX_MASK	(SDMA_0_CAUSE_TXBUF | SDMA_0_CAUSE_TXEND \
+		| SDMA_1_CAUSE_TXBUF | SDMA_1_CAUSE_TXEND)
+
+/* SDMA Interrupt registers */
+#define	SDMA_INTR_CAUSE			0x0000
+#define	SDMA_INTR_MASK			0x0080
+
+/* Baud Rate Generator Interface Registers */
+#define	BRG_BCR				0x0000
+#define	BRG_BTR				0x0004
+
+/*
+ * Define how this driver is known to the outside (we've been assigned a
+ * range on the "Low-density serial ports" major).
+ */
+#define MPSC_MAJOR			204
+#define MPSC_MINOR_START		44
+#define	MPSC_DRIVER_NAME		"MPSC"
+#define	MPSC_DEV_NAME			"ttyMM"
+#define	MPSC_VERSION			"1.00"
+
+static struct mpsc_port_info mpsc_ports[MPSC_NUM_CTLRS];
+static struct mpsc_shared_regs mpsc_shared_regs;
+static struct uart_driver mpsc_reg;
+
+static void mpsc_start_rx(struct mpsc_port_info *pi);
+static void mpsc_free_ring_mem(struct mpsc_port_info *pi);
+static void mpsc_release_port(struct uart_port *port);
+/*
+ ******************************************************************************
+ *
+ * Baud Rate Generator Routines (BRG)
+ *
+ ******************************************************************************
+ */
+static void mpsc_brg_init(struct mpsc_port_info *pi, u32 clk_src)
+{
+	u32	v;
+
+	v = (pi->mirror_regs) ? pi->BRG_BCR_m : readl(pi->brg_base + BRG_BCR);
+	v = (v & ~(0xf << 18)) | ((clk_src & 0xf) << 18);
+
+	if (pi->brg_can_tune)
+		v &= ~(1 << 25);
+
+	if (pi->mirror_regs)
+		pi->BRG_BCR_m = v;
+	writel(v, pi->brg_base + BRG_BCR);
+
+	writel(readl(pi->brg_base + BRG_BTR) & 0xffff0000,
+		pi->brg_base + BRG_BTR);
+}
+
+static void mpsc_brg_enable(struct mpsc_port_info *pi)
+{
+	u32	v;
+
+	v = (pi->mirror_regs) ? pi->BRG_BCR_m : readl(pi->brg_base + BRG_BCR);
+	v |= (1 << 16);
+
+	if (pi->mirror_regs)
+		pi->BRG_BCR_m = v;
+	writel(v, pi->brg_base + BRG_BCR);
+}
+
+static void mpsc_brg_disable(struct mpsc_port_info *pi)
+{
+	u32	v;
+
+	v = (pi->mirror_regs) ? pi->BRG_BCR_m : readl(pi->brg_base + BRG_BCR);
+	v &= ~(1 << 16);
+
+	if (pi->mirror_regs)
+		pi->BRG_BCR_m = v;
+	writel(v, pi->brg_base + BRG_BCR);
+}
+
+/*
+ * To set the baud, we adjust the CDV field in the BRG_BCR reg.
+ * From manual: Baud = clk / ((CDV+1)*2) ==> CDV = (clk / (baud*2)) - 1.
+ * However, the input clock is divided by 16 in the MPSC b/c of how
+ * 'MPSC_MMCRH' was set up so we have to divide the 'clk' used in our
+ * calculation by 16 to account for that.  So the real calculation
+ * that accounts for the way the mpsc is set up is:
+ * CDV = (clk / (baud*2*16)) - 1 ==> CDV = (clk / (baud << 5)) - 1.
+ */
+static void mpsc_set_baudrate(struct mpsc_port_info *pi, u32 baud)
+{
+	u32	cdv = (pi->port.uartclk / (baud << 5)) - 1;
+	u32	v;
+
+	mpsc_brg_disable(pi);
+	v = (pi->mirror_regs) ? pi->BRG_BCR_m : readl(pi->brg_base + BRG_BCR);
+	v = (v & 0xffff0000) | (cdv & 0xffff);
+
+	if (pi->mirror_regs)
+		pi->BRG_BCR_m = v;
+	writel(v, pi->brg_base + BRG_BCR);
+	mpsc_brg_enable(pi);
+}
+
+/*
+ ******************************************************************************
+ *
+ * Serial DMA Routines (SDMA)
+ *
+ ******************************************************************************
+ */
+
+static void mpsc_sdma_burstsize(struct mpsc_port_info *pi, u32 burst_size)
+{
+	u32	v;
+
+	pr_debug("mpsc_sdma_burstsize[%d]: burst_size: %d\n",
+			pi->port.line, burst_size);
+
+	burst_size >>= 3; /* Divide by 8 b/c reg values are 8-byte chunks */
+
+	if (burst_size < 2)
+		v = 0x0;	/* 1 64-bit word */
+	else if (burst_size < 4)
+		v = 0x1;	/* 2 64-bit words */
+	else if (burst_size < 8)
+		v = 0x2;	/* 4 64-bit words */
+	else
+		v = 0x3;	/* 8 64-bit words */
+
+	writel((readl(pi->sdma_base + SDMA_SDC) & (0x3 << 12)) | (v << 12),
+		pi->sdma_base + SDMA_SDC);
+}
+
+static void mpsc_sdma_init(struct mpsc_port_info *pi, u32 burst_size)
+{
+	pr_debug("mpsc_sdma_init[%d]: burst_size: %d\n", pi->port.line,
+		burst_size);
+
+	writel((readl(pi->sdma_base + SDMA_SDC) & 0x3ff) | 0x03f,
+		pi->sdma_base + SDMA_SDC);
+	mpsc_sdma_burstsize(pi, burst_size);
+}
+
+static u32 mpsc_sdma_intr_mask(struct mpsc_port_info *pi, u32 mask)
+{
+	u32	old, v;
+
+	pr_debug("mpsc_sdma_intr_mask[%d]: mask: 0x%x\n", pi->port.line, mask);
+
+	old = v = (pi->mirror_regs) ? pi->shared_regs->SDMA_INTR_MASK_m :
+		readl(pi->shared_regs->sdma_intr_base + SDMA_INTR_MASK);
+
+	mask &= 0xf;
+	if (pi->port.line)
+		mask <<= 8;
+	v &= ~mask;
+
+	if (pi->mirror_regs)
+		pi->shared_regs->SDMA_INTR_MASK_m = v;
+	writel(v, pi->shared_regs->sdma_intr_base + SDMA_INTR_MASK);
+
+	if (pi->port.line)
+		old >>= 8;
+	return old & 0xf;
+}
+
+static void mpsc_sdma_intr_unmask(struct mpsc_port_info *pi, u32 mask)
+{
+	u32	v;
+
+	pr_debug("mpsc_sdma_intr_unmask[%d]: mask: 0x%x\n", pi->port.line,mask);
+
+	v = (pi->mirror_regs) ? pi->shared_regs->SDMA_INTR_MASK_m
+		: readl(pi->shared_regs->sdma_intr_base + SDMA_INTR_MASK);
+
+	mask &= 0xf;
+	if (pi->port.line)
+		mask <<= 8;
+	v |= mask;
+
+	if (pi->mirror_regs)
+		pi->shared_regs->SDMA_INTR_MASK_m = v;
+	writel(v, pi->shared_regs->sdma_intr_base + SDMA_INTR_MASK);
+}
+
+static void mpsc_sdma_intr_ack(struct mpsc_port_info *pi)
+{
+	pr_debug("mpsc_sdma_intr_ack[%d]: Acknowledging IRQ\n", pi->port.line);
+
+	if (pi->mirror_regs)
+		pi->shared_regs->SDMA_INTR_CAUSE_m = 0;
+	writeb(0x00, pi->shared_regs->sdma_intr_base + SDMA_INTR_CAUSE
+			+ pi->port.line);
+}
+
+static void mpsc_sdma_set_rx_ring(struct mpsc_port_info *pi,
+		struct mpsc_rx_desc *rxre_p)
+{
+	pr_debug("mpsc_sdma_set_rx_ring[%d]: rxre_p: 0x%x\n",
+		pi->port.line, (u32)rxre_p);
+
+	writel((u32)rxre_p, pi->sdma_base + SDMA_SCRDP);
+}
+
+static void mpsc_sdma_set_tx_ring(struct mpsc_port_info *pi,
+		struct mpsc_tx_desc *txre_p)
+{
+	writel((u32)txre_p, pi->sdma_base + SDMA_SFTDP);
+	writel((u32)txre_p, pi->sdma_base + SDMA_SCTDP);
+}
+
+static void mpsc_sdma_cmd(struct mpsc_port_info *pi, u32 val)
+{
+	u32	v;
+
+	v = readl(pi->sdma_base + SDMA_SDCM);
+	if (val)
+		v |= val;
+	else
+		v = 0;
+	wmb();
+	writel(v, pi->sdma_base + SDMA_SDCM);
+	wmb();
+}
+
+static uint mpsc_sdma_tx_active(struct mpsc_port_info *pi)
+{
+	return readl(pi->sdma_base + SDMA_SDCM) & SDMA_SDCM_TXD;
+}
+
+static void mpsc_sdma_start_tx(struct mpsc_port_info *pi)
+{
+	struct mpsc_tx_desc *txre, *txre_p;
+
+	/* If tx isn't running & there's a desc ready to go, start it */
+	if (!mpsc_sdma_tx_active(pi)) {
+		txre = (struct mpsc_tx_desc *)(pi->txr
+				+ (pi->txr_tail * MPSC_TXRE_SIZE));
+		dma_cache_sync(pi->port.dev, (void *)txre, MPSC_TXRE_SIZE,
+				DMA_FROM_DEVICE);
+#if defined(CONFIG_PPC32) && !defined(CONFIG_NOT_COHERENT_CACHE)
+		if (pi->cache_mgmt) /* GT642[46]0 Res #COMM-2 */
+			invalidate_dcache_range((ulong)txre,
+					(ulong)txre + MPSC_TXRE_SIZE);
+#endif
+
+		if (be32_to_cpu(txre->cmdstat) & SDMA_DESC_CMDSTAT_O) {
+			txre_p = (struct mpsc_tx_desc *)
+				(pi->txr_p + (pi->txr_tail * MPSC_TXRE_SIZE));
+
+			mpsc_sdma_set_tx_ring(pi, txre_p);
+			mpsc_sdma_cmd(pi, SDMA_SDCM_STD | SDMA_SDCM_TXD);
+		}
+	}
+}
+
+static void mpsc_sdma_stop(struct mpsc_port_info *pi)
+{
+	pr_debug("mpsc_sdma_stop[%d]: Stopping SDMA\n", pi->port.line);
+
+	/* Abort any SDMA transfers */
+	mpsc_sdma_cmd(pi, 0);
+	mpsc_sdma_cmd(pi, SDMA_SDCM_AR | SDMA_SDCM_AT);
+
+	/* Clear the SDMA current and first TX and RX pointers */
+	mpsc_sdma_set_tx_ring(pi, NULL);
+	mpsc_sdma_set_rx_ring(pi, NULL);
+
+	/* Disable interrupts */
+	mpsc_sdma_intr_mask(pi, 0xf);
+	mpsc_sdma_intr_ack(pi);
+}
+
+/*
+ ******************************************************************************
+ *
+ * Multi-Protocol Serial Controller Routines (MPSC)
+ *
+ ******************************************************************************
+ */
+
+static void mpsc_hw_init(struct mpsc_port_info *pi)
+{
+	u32	v;
+
+	pr_debug("mpsc_hw_init[%d]: Initializing hardware\n", pi->port.line);
+
+	/* Set up clock routing */
+	if (pi->mirror_regs) {
+		v = pi->shared_regs->MPSC_MRR_m;
+		v &= ~0x1c7;
+		pi->shared_regs->MPSC_MRR_m = v;
+		writel(v, pi->shared_regs->mpsc_routing_base + MPSC_MRR);
+
+		v = pi->shared_regs->MPSC_RCRR_m;
+		v = (v & ~0xf0f) | 0x100;
+		pi->shared_regs->MPSC_RCRR_m = v;
+		writel(v, pi->shared_regs->mpsc_routing_base + MPSC_RCRR);
+
+		v = pi->shared_regs->MPSC_TCRR_m;
+		v = (v & ~0xf0f) | 0x100;
+		pi->shared_regs->MPSC_TCRR_m = v;
+		writel(v, pi->shared_regs->mpsc_routing_base + MPSC_TCRR);
+	} else {
+		v = readl(pi->shared_regs->mpsc_routing_base + MPSC_MRR);
+		v &= ~0x1c7;
+		writel(v, pi->shared_regs->mpsc_routing_base + MPSC_MRR);
+
+		v = readl(pi->shared_regs->mpsc_routing_base + MPSC_RCRR);
+		v = (v & ~0xf0f) | 0x100;
+		writel(v, pi->shared_regs->mpsc_routing_base + MPSC_RCRR);
+
+		v = readl(pi->shared_regs->mpsc_routing_base + MPSC_TCRR);
+		v = (v & ~0xf0f) | 0x100;
+		writel(v, pi->shared_regs->mpsc_routing_base + MPSC_TCRR);
+	}
+
+	/* Put MPSC in UART mode & enabel Tx/Rx egines */
+	writel(0x000004c4, pi->mpsc_base + MPSC_MMCRL);
+
+	/* No preamble, 16x divider, low-latency, */
+	writel(0x04400400, pi->mpsc_base + MPSC_MMCRH);
+	mpsc_set_baudrate(pi, pi->default_baud);
+
+	if (pi->mirror_regs) {
+		pi->MPSC_CHR_1_m = 0;
+		pi->MPSC_CHR_2_m = 0;
+	}
+	writel(0, pi->mpsc_base + MPSC_CHR_1);
+	writel(0, pi->mpsc_base + MPSC_CHR_2);
+	writel(pi->mpsc_max_idle, pi->mpsc_base + MPSC_CHR_3);
+	writel(0, pi->mpsc_base + MPSC_CHR_4);
+	writel(0, pi->mpsc_base + MPSC_CHR_5);
+	writel(0, pi->mpsc_base + MPSC_CHR_6);
+	writel(0, pi->mpsc_base + MPSC_CHR_7);
+	writel(0, pi->mpsc_base + MPSC_CHR_8);
+	writel(0, pi->mpsc_base + MPSC_CHR_9);
+	writel(0, pi->mpsc_base + MPSC_CHR_10);
+}
+
+static void mpsc_enter_hunt(struct mpsc_port_info *pi)
+{
+	pr_debug("mpsc_enter_hunt[%d]: Hunting...\n", pi->port.line);
+
+	if (pi->mirror_regs) {
+		writel(pi->MPSC_CHR_2_m | MPSC_CHR_2_EH,
+			pi->mpsc_base + MPSC_CHR_2);
+		/* Erratum prevents reading CHR_2 so just delay for a while */
+		udelay(100);
+	} else {
+		writel(readl(pi->mpsc_base + MPSC_CHR_2) | MPSC_CHR_2_EH,
+				pi->mpsc_base + MPSC_CHR_2);
+
+		while (readl(pi->mpsc_base + MPSC_CHR_2) & MPSC_CHR_2_EH)
+			udelay(10);
+	}
+}
+
+static void mpsc_freeze(struct mpsc_port_info *pi)
+{
+	u32	v;
+
+	pr_debug("mpsc_freeze[%d]: Freezing\n", pi->port.line);
+
+	v = (pi->mirror_regs) ? pi->MPSC_MPCR_m :
+		readl(pi->mpsc_base + MPSC_MPCR);
+	v |= MPSC_MPCR_FRZ;
+
+	if (pi->mirror_regs)
+		pi->MPSC_MPCR_m = v;
+	writel(v, pi->mpsc_base + MPSC_MPCR);
+}
+
+static void mpsc_unfreeze(struct mpsc_port_info *pi)
+{
+	u32	v;
+
+	v = (pi->mirror_regs) ? pi->MPSC_MPCR_m :
+		readl(pi->mpsc_base + MPSC_MPCR);
+	v &= ~MPSC_MPCR_FRZ;
+
+	if (pi->mirror_regs)
+		pi->MPSC_MPCR_m = v;
+	writel(v, pi->mpsc_base + MPSC_MPCR);
+
+	pr_debug("mpsc_unfreeze[%d]: Unfrozen\n", pi->port.line);
+}
+
+static void mpsc_set_char_length(struct mpsc_port_info *pi, u32 len)
+{
+	u32	v;
+
+	pr_debug("mpsc_set_char_length[%d]: char len: %d\n", pi->port.line,len);
+
+	v = (pi->mirror_regs) ? pi->MPSC_MPCR_m :
+		readl(pi->mpsc_base + MPSC_MPCR);
+	v = (v & ~(0x3 << 12)) | ((len & 0x3) << 12);
+
+	if (pi->mirror_regs)
+		pi->MPSC_MPCR_m = v;
+	writel(v, pi->mpsc_base + MPSC_MPCR);
+}
+
+static void mpsc_set_stop_bit_length(struct mpsc_port_info *pi, u32 len)
+{
+	u32	v;
+
+	pr_debug("mpsc_set_stop_bit_length[%d]: stop bits: %d\n",
+		pi->port.line, len);
+
+	v = (pi->mirror_regs) ? pi->MPSC_MPCR_m :
+		readl(pi->mpsc_base + MPSC_MPCR);
+
+	v = (v & ~(1 << 14)) | ((len & 0x1) << 14);
+
+	if (pi->mirror_regs)
+		pi->MPSC_MPCR_m = v;
+	writel(v, pi->mpsc_base + MPSC_MPCR);
+}
+
+static void mpsc_set_parity(struct mpsc_port_info *pi, u32 p)
+{
+	u32	v;
+
+	pr_debug("mpsc_set_parity[%d]: parity bits: 0x%x\n", pi->port.line, p);
+
+	v = (pi->mirror_regs) ? pi->MPSC_CHR_2_m :
+		readl(pi->mpsc_base + MPSC_CHR_2);
+
+	p &= 0x3;
+	v = (v & ~0xc000c) | (p << 18) | (p << 2);
+
+	if (pi->mirror_regs)
+		pi->MPSC_CHR_2_m = v;
+	writel(v, pi->mpsc_base + MPSC_CHR_2);
+}
+
+/*
+ ******************************************************************************
+ *
+ * Driver Init Routines
+ *
+ ******************************************************************************
+ */
+
+static void mpsc_init_hw(struct mpsc_port_info *pi)
+{
+	pr_debug("mpsc_init_hw[%d]: Initializing\n", pi->port.line);
+
+	mpsc_brg_init(pi, pi->brg_clk_src);
+	mpsc_brg_enable(pi);
+	mpsc_sdma_init(pi, dma_get_cache_alignment());	/* burst a cacheline */
+	mpsc_sdma_stop(pi);
+	mpsc_hw_init(pi);
+}
+
+static int mpsc_alloc_ring_mem(struct mpsc_port_info *pi)
+{
+	int rc = 0;
+
+	pr_debug("mpsc_alloc_ring_mem[%d]: Allocating ring mem\n",
+		pi->port.line);
+
+	if (!pi->dma_region) {
+		if (!dma_supported(pi->port.dev, 0xffffffff)) {
+			printk(KERN_ERR "MPSC: Inadequate DMA support\n");
+			rc = -ENXIO;
+		} else if ((pi->dma_region = dma_alloc_noncoherent(pi->port.dev,
+						MPSC_DMA_ALLOC_SIZE,
+						&pi->dma_region_p, GFP_KERNEL))
+				== NULL) {
+			printk(KERN_ERR "MPSC: Can't alloc Desc region\n");
+			rc = -ENOMEM;
+		}
+	}
+
+	return rc;
+}
+
+static void mpsc_free_ring_mem(struct mpsc_port_info *pi)
+{
+	pr_debug("mpsc_free_ring_mem[%d]: Freeing ring mem\n", pi->port.line);
+
+	if (pi->dma_region) {
+		dma_free_noncoherent(pi->port.dev, MPSC_DMA_ALLOC_SIZE,
+				pi->dma_region, pi->dma_region_p);
+		pi->dma_region = NULL;
+		pi->dma_region_p = (dma_addr_t)NULL;
+	}
+}
+
+static void mpsc_init_rings(struct mpsc_port_info *pi)
+{
+	struct mpsc_rx_desc *rxre;
+	struct mpsc_tx_desc *txre;
+	dma_addr_t dp, dp_p;
+	u8 *bp, *bp_p;
+	int i;
+
+	pr_debug("mpsc_init_rings[%d]: Initializing rings\n", pi->port.line);
+
+	BUG_ON(pi->dma_region == NULL);
+
+	memset(pi->dma_region, 0, MPSC_DMA_ALLOC_SIZE);
+
+	/*
+	 * Descriptors & buffers are multiples of cacheline size and must be
+	 * cacheline aligned.
+	 */
+	dp = ALIGN((u32)pi->dma_region, dma_get_cache_alignment());
+	dp_p = ALIGN((u32)pi->dma_region_p, dma_get_cache_alignment());
+
+	/*
+	 * Partition dma region into rx ring descriptor, rx buffers,
+	 * tx ring descriptors, and tx buffers.
+	 */
+	pi->rxr = dp;
+	pi->rxr_p = dp_p;
+	dp += MPSC_RXR_SIZE;
+	dp_p += MPSC_RXR_SIZE;
+
+	pi->rxb = (u8 *)dp;
+	pi->rxb_p = (u8 *)dp_p;
+	dp += MPSC_RXB_SIZE;
+	dp_p += MPSC_RXB_SIZE;
+
+	pi->rxr_posn = 0;
+
+	pi->txr = dp;
+	pi->txr_p = dp_p;
+	dp += MPSC_TXR_SIZE;
+	dp_p += MPSC_TXR_SIZE;
+
+	pi->txb = (u8 *)dp;
+	pi->txb_p = (u8 *)dp_p;
+
+	pi->txr_head = 0;
+	pi->txr_tail = 0;
+
+	/* Init rx ring descriptors */
+	dp = pi->rxr;
+	dp_p = pi->rxr_p;
+	bp = pi->rxb;
+	bp_p = pi->rxb_p;
+
+	for (i = 0; i < MPSC_RXR_ENTRIES; i++) {
+		rxre = (struct mpsc_rx_desc *)dp;
+
+		rxre->bufsize = cpu_to_be16(MPSC_RXBE_SIZE);
+		rxre->bytecnt = cpu_to_be16(0);
+		rxre->cmdstat = cpu_to_be32(SDMA_DESC_CMDSTAT_O
+				| SDMA_DESC_CMDSTAT_EI | SDMA_DESC_CMDSTAT_F
+				| SDMA_DESC_CMDSTAT_L);
+		rxre->link = cpu_to_be32(dp_p + MPSC_RXRE_SIZE);
+		rxre->buf_ptr = cpu_to_be32(bp_p);
+
+		dp += MPSC_RXRE_SIZE;
+		dp_p += MPSC_RXRE_SIZE;
+		bp += MPSC_RXBE_SIZE;
+		bp_p += MPSC_RXBE_SIZE;
+	}
+	rxre->link = cpu_to_be32(pi->rxr_p);	/* Wrap last back to first */
+
+	/* Init tx ring descriptors */
+	dp = pi->txr;
+	dp_p = pi->txr_p;
+	bp = pi->txb;
+	bp_p = pi->txb_p;
+
+	for (i = 0; i < MPSC_TXR_ENTRIES; i++) {
+		txre = (struct mpsc_tx_desc *)dp;
+
+		txre->link = cpu_to_be32(dp_p + MPSC_TXRE_SIZE);
+		txre->buf_ptr = cpu_to_be32(bp_p);
+
+		dp += MPSC_TXRE_SIZE;
+		dp_p += MPSC_TXRE_SIZE;
+		bp += MPSC_TXBE_SIZE;
+		bp_p += MPSC_TXBE_SIZE;
+	}
+	txre->link = cpu_to_be32(pi->txr_p);	/* Wrap last back to first */
+
+	dma_cache_sync(pi->port.dev, (void *)pi->dma_region,
+			MPSC_DMA_ALLOC_SIZE, DMA_BIDIRECTIONAL);
+#if defined(CONFIG_PPC32) && !defined(CONFIG_NOT_COHERENT_CACHE)
+		if (pi->cache_mgmt) /* GT642[46]0 Res #COMM-2 */
+			flush_dcache_range((ulong)pi->dma_region,
+					(ulong)pi->dma_region
+					+ MPSC_DMA_ALLOC_SIZE);
+#endif
+
+	return;
+}
+
+static void mpsc_uninit_rings(struct mpsc_port_info *pi)
+{
+	pr_debug("mpsc_uninit_rings[%d]: Uninitializing rings\n",pi->port.line);
+
+	BUG_ON(pi->dma_region == NULL);
+
+	pi->rxr = 0;
+	pi->rxr_p = 0;
+	pi->rxb = NULL;
+	pi->rxb_p = NULL;
+	pi->rxr_posn = 0;
+
+	pi->txr = 0;
+	pi->txr_p = 0;
+	pi->txb = NULL;
+	pi->txb_p = NULL;
+	pi->txr_head = 0;
+	pi->txr_tail = 0;
+}
+
+static int mpsc_make_ready(struct mpsc_port_info *pi)
+{
+	int rc;
+
+	pr_debug("mpsc_make_ready[%d]: Making cltr ready\n", pi->port.line);
+
+	if (!pi->ready) {
+		mpsc_init_hw(pi);
+		if ((rc = mpsc_alloc_ring_mem(pi)))
+			return rc;
+		mpsc_init_rings(pi);
+		pi->ready = 1;
+	}
+
+	return 0;
+}
+
+#ifdef CONFIG_CONSOLE_POLL
+static int serial_polled;
+#endif
+
+/*
+ ******************************************************************************
+ *
+ * Interrupt Handling Routines
+ *
+ ******************************************************************************
+ */
+
+static int mpsc_rx_intr(struct mpsc_port_info *pi)
+{
+	struct mpsc_rx_desc *rxre;
+	struct tty_struct *tty = pi->port.state->port.tty;
+	u32	cmdstat, bytes_in, i;
+	int	rc = 0;
+	u8	*bp;
+	char	flag = TTY_NORMAL;
+
+	pr_debug("mpsc_rx_intr[%d]: Handling Rx intr\n", pi->port.line);
+
+	rxre = (struct mpsc_rx_desc *)(pi->rxr + (pi->rxr_posn*MPSC_RXRE_SIZE));
+
+	dma_cache_sync(pi->port.dev, (void *)rxre, MPSC_RXRE_SIZE,
+			DMA_FROM_DEVICE);
+#if defined(CONFIG_PPC32) && !defined(CONFIG_NOT_COHERENT_CACHE)
+	if (pi->cache_mgmt) /* GT642[46]0 Res #COMM-2 */
+		invalidate_dcache_range((ulong)rxre,
+				(ulong)rxre + MPSC_RXRE_SIZE);
+#endif
+
+	/*
+	 * Loop through Rx descriptors handling ones that have been completed.
+	 */
+	while (!((cmdstat = be32_to_cpu(rxre->cmdstat))
+				& SDMA_DESC_CMDSTAT_O)) {
+		bytes_in = be16_to_cpu(rxre->bytecnt);
+#ifdef CONFIG_CONSOLE_POLL
+		if (unlikely(serial_polled)) {
+			serial_polled = 0;
+			return 0;
+		}
+#endif
+		/* Following use of tty struct directly is deprecated */
+		if (unlikely(tty_buffer_request_room(tty, bytes_in)
+					< bytes_in)) {
+			if (tty->low_latency)
+				tty_flip_buffer_push(tty);
+			/*
+			 * If this failed then we will throw away the bytes
+			 * but must do so to clear interrupts.
+			 */
+		}
+
+		bp = pi->rxb + (pi->rxr_posn * MPSC_RXBE_SIZE);
+		dma_cache_sync(pi->port.dev, (void *)bp, MPSC_RXBE_SIZE,
+				DMA_FROM_DEVICE);
+#if defined(CONFIG_PPC32) && !defined(CONFIG_NOT_COHERENT_CACHE)
+		if (pi->cache_mgmt) /* GT642[46]0 Res #COMM-2 */
+			invalidate_dcache_range((ulong)bp,
+					(ulong)bp + MPSC_RXBE_SIZE);
+#endif
+
+		/*
+		 * Other than for parity error, the manual provides little
+		 * info on what data will be in a frame flagged by any of
+		 * these errors.  For parity error, it is the last byte in
+		 * the buffer that had the error.  As for the rest, I guess
+		 * we'll assume there is no data in the buffer.
+		 * If there is...it gets lost.
+		 */
+		if (unlikely(cmdstat & (SDMA_DESC_CMDSTAT_BR
+						| SDMA_DESC_CMDSTAT_FR
+						| SDMA_DESC_CMDSTAT_OR))) {
+
+			pi->port.icount.rx++;
+
+			if (cmdstat & SDMA_DESC_CMDSTAT_BR) {	/* Break */
+				pi->port.icount.brk++;
+
+				if (uart_handle_break(&pi->port))
+					goto next_frame;
+			} else if (cmdstat & SDMA_DESC_CMDSTAT_FR) {
+				pi->port.icount.frame++;
+			} else if (cmdstat & SDMA_DESC_CMDSTAT_OR) {
+				pi->port.icount.overrun++;
+			}
+
+			cmdstat &= pi->port.read_status_mask;
+
+			if (cmdstat & SDMA_DESC_CMDSTAT_BR)
+				flag = TTY_BREAK;
+			else if (cmdstat & SDMA_DESC_CMDSTAT_FR)
+				flag = TTY_FRAME;
+			else if (cmdstat & SDMA_DESC_CMDSTAT_OR)
+				flag = TTY_OVERRUN;
+			else if (cmdstat & SDMA_DESC_CMDSTAT_PE)
+				flag = TTY_PARITY;
+		}
+
+		if (uart_handle_sysrq_char(&pi->port, *bp)) {
+			bp++;
+			bytes_in--;
+#ifdef CONFIG_CONSOLE_POLL
+			if (unlikely(serial_polled)) {
+				serial_polled = 0;
+				return 0;
+			}
+#endif
+			goto next_frame;
+		}
+
+		if ((unlikely(cmdstat & (SDMA_DESC_CMDSTAT_BR
+						| SDMA_DESC_CMDSTAT_FR
+						| SDMA_DESC_CMDSTAT_OR)))
+				&& !(cmdstat & pi->port.ignore_status_mask)) {
+			tty_insert_flip_char(tty, *bp, flag);
+		} else {
+			for (i=0; i<bytes_in; i++)
+				tty_insert_flip_char(tty, *bp++, TTY_NORMAL);
+
+			pi->port.icount.rx += bytes_in;
+		}
+
+next_frame:
+		rxre->bytecnt = cpu_to_be16(0);
+		wmb();
+		rxre->cmdstat = cpu_to_be32(SDMA_DESC_CMDSTAT_O
+				| SDMA_DESC_CMDSTAT_EI | SDMA_DESC_CMDSTAT_F
+				| SDMA_DESC_CMDSTAT_L);
+		wmb();
+		dma_cache_sync(pi->port.dev, (void *)rxre, MPSC_RXRE_SIZE,
+				DMA_BIDIRECTIONAL);
+#if defined(CONFIG_PPC32) && !defined(CONFIG_NOT_COHERENT_CACHE)
+		if (pi->cache_mgmt) /* GT642[46]0 Res #COMM-2 */
+			flush_dcache_range((ulong)rxre,
+					(ulong)rxre + MPSC_RXRE_SIZE);
+#endif
+
+		/* Advance to next descriptor */
+		pi->rxr_posn = (pi->rxr_posn + 1) & (MPSC_RXR_ENTRIES - 1);
+		rxre = (struct mpsc_rx_desc *)
+			(pi->rxr + (pi->rxr_posn * MPSC_RXRE_SIZE));
+		dma_cache_sync(pi->port.dev, (void *)rxre, MPSC_RXRE_SIZE,
+				DMA_FROM_DEVICE);
+#if defined(CONFIG_PPC32) && !defined(CONFIG_NOT_COHERENT_CACHE)
+		if (pi->cache_mgmt) /* GT642[46]0 Res #COMM-2 */
+			invalidate_dcache_range((ulong)rxre,
+					(ulong)rxre + MPSC_RXRE_SIZE);
+#endif
+		rc = 1;
+	}
+
+	/* Restart rx engine, if its stopped */
+	if ((readl(pi->sdma_base + SDMA_SDCM) & SDMA_SDCM_ERD) == 0)
+		mpsc_start_rx(pi);
+
+	tty_flip_buffer_push(tty);
+	return rc;
+}
+
+static void mpsc_setup_tx_desc(struct mpsc_port_info *pi, u32 count, u32 intr)
+{
+	struct mpsc_tx_desc *txre;
+
+	txre = (struct mpsc_tx_desc *)(pi->txr
+			+ (pi->txr_head * MPSC_TXRE_SIZE));
+
+	txre->bytecnt = cpu_to_be16(count);
+	txre->shadow = txre->bytecnt;
+	wmb();			/* ensure cmdstat is last field updated */
+	txre->cmdstat = cpu_to_be32(SDMA_DESC_CMDSTAT_O | SDMA_DESC_CMDSTAT_F
+			| SDMA_DESC_CMDSTAT_L
+			| ((intr) ? SDMA_DESC_CMDSTAT_EI : 0));
+	wmb();
+	dma_cache_sync(pi->port.dev, (void *)txre, MPSC_TXRE_SIZE,
+			DMA_BIDIRECTIONAL);
+#if defined(CONFIG_PPC32) && !defined(CONFIG_NOT_COHERENT_CACHE)
+	if (pi->cache_mgmt) /* GT642[46]0 Res #COMM-2 */
+		flush_dcache_range((ulong)txre,
+				(ulong)txre + MPSC_TXRE_SIZE);
+#endif
+}
+
+static void mpsc_copy_tx_data(struct mpsc_port_info *pi)
+{
+	struct circ_buf *xmit = &pi->port.state->xmit;
+	u8 *bp;
+	u32 i;