Re: [microblaze-uclinux] [PATCHv2] [RFC] Xilinx MPMC SDMA subsystem
From: Steven J. Magnani
Date: Tue Apr 27 2010 - 22:33:15 EST
On Wed, 2010-04-28 at 02:06 +0400, Sergey Temerkhanov wrote:
> This is the 2nd version of Xilinx MPMC LocalLink SDMA subsystem
>
> Changelog v2:
> * Changed the functions and struct definition prefix from sdma_ to xllsdma_
> * Platform bus bindings and various changes by Steven J. Magnani.
> * Moved source files from arch/powerpc/sysdev to global locations and added
> CONFIG_XLLSDMA option.
>
> Regards, Sergey Temerkhanov,
> Cifronic ZAO
>
> diff -r baced9e29ab5 drivers/dma/Kconfig
> --- a/drivers/dma/Kconfig Tue Apr 27 20:48:50 2010 +0400
> +++ b/drivers/dma/Kconfig Wed Apr 28 02:00:51 2010 +0400
> @@ -97,6 +97,14 @@
> Support the TXx9 SoC internal DMA controller. This can be
> integrated in chips such as the Toshiba TX4927/38/39.
>
> +config XLLSDMA
> + bool "Xilinx MPMC DMA support"
> + depends on XILINX_VIRTEX || MICROBLAZE
> + select DMA_ENGINE
> + help
> + Support fot Xilinx MPMC LocalLink SDMA. Virtex FPGA family
> + has it integrated or fabric-based.
> +
fot --> for
Since the xllsdma driver provides services to other drivers - not to userland -
I think this would be better as a "silent" option, selected automatically when
something like ll_temac or the forthcoming Xilinx DMA engine is selected.
If we do it that way, note that XLLSDMA is independent of DMA_ENGINE so
drivers/Makefile will need to be patched so that the dma subdirectory is
always "y".
>
> config DMA_ENGINE
> bool
>
> @@ -133,3 +141,5 @@
> DMA Device driver.
>
> endif
> +
> +
Some extra white space crept in at the end of the file.
> diff -r baced9e29ab5 drivers/dma/Makefile
> --- a/drivers/dma/Makefile Tue Apr 27 20:48:50 2010 +0400
> +++ b/drivers/dma/Makefile Wed Apr 28 02:00:51 2010 +0400
> @@ -10,3 +10,4 @@
> obj-$(CONFIG_AT_HDMAC) += at_hdmac.o
> obj-$(CONFIG_MX3_IPU) += ipu/
> obj-$(CONFIG_TXX9_DMAC) += txx9dmac.o
> +obj-$(CONFIG_XLLSDMA) += xllsdma.o
> diff -r baced9e29ab5 drivers/dma/xllsdma.c
> --- /dev/null Thu Jan 01 00:00:00 1970 +0000
> +++ b/drivers/dma/xllsdma.c Wed Apr 28 02:00:51 2010 +0400
> @@ -0,0 +1,887 @@
> +/*
> + * SDMA subsystem support for Xilinx MPMC.
> + *
> + * Author: Sergey Temerkhanov
> + * Platform Bus by Steven J. Magnani
> + *
> + * Copyright (c) 2008-2010 Cifronic ZAO
> + *
> + * This program is free software; you can redistribute it and/or modify it
> + * under the terms of the GNU General Public License as published by the
> + * Free Software Foundation; either version 2 of the License, or (at your
> + * option) any later version.
> + *
> + */
> +
> +#include <linux/delay.h>
> +#include <linux/kernel.h>
> +#include <linux/init.h>
> +#include <linux/module.h>
> +#include <linux/init.h>
> +#include <linux/errno.h>
> +#include <linux/interrupt.h>
> +#include <linux/mutex.h>
> +#include <linux/wait.h>
> +#include <linux/list.h>
> +#include <linux/io.h>
> +#include <linux/xllsdma.h>
> +
> +#include <linux/of_device.h>
> +#include <linux/of_platform.h>
> +
> +#define DRV_VERSION "0.1.0"
> +#define DRV_NAME "sdma"
> +
> +MODULE_AUTHOR("Sergey Temerkhanov <temerkhanov@xxxxxxxxxxx>");
> +MODULE_DESCRIPTION("Xilinx SDMA driver");
> +MODULE_LICENSE("GPL");
> +MODULE_VERSION(DRV_VERSION);
> +
> +LIST_HEAD(mpmc_devs);
> +DEFINE_MUTEX(mpmc_devs_lock);
> +
> +enum {
> + XLLSDMA_TX_REGS = 0x00, /* TX channel registers beginning */
> + XLLSDMA_RX_REGS = 0x20, /* RX channel registers beginning */
> + XLLSDMA_DMACR = 0x40, /* DMA control register */
> +
> + XLLSDMA_NDESCR = 0x00, /* Next descriptor address */
> + XLLSDMA_BUFA = 0x04, /* Current buffer address */
> + XLLSDMA_BUFL = 0x08, /* Current buffer length */
> + XLLSDMA_CDESCR = 0x0C, /* Current descriptor address */
> + XLLSDMA_TDESCR = 0x10, /* Tail descriptor address */
> + XLLSDMA_CR = 0x14, /* Channel control */
> + XLLSDMA_IRQ = 0x18, /* Interrupt register */
> + XLLSDMA_SR = 0x1C, /* Status */
> +};
> +
> +enum {
> + XLLSDMA_CR_IRQ_TIMEOUT_MSK = (0xFF << 24), /* Interrupt coalesce timeout */
> + XLLSDMA_CR_IRQ_THRESHOLD_MSK = (0xFF << 16), /* Interrupt coalesce count */
> + XLLSDMA_CR_MSB_ADDR_MSK = (0xF << 12), /* MSB for 36 bit addressing */
> + XLLSDMA_CR_APP_EN = (1 << 11), /* Application data mask enable */
> + XLLSDMA_CR_1_BIT_CNT = (1 << 10), /* All interrupt counters are 1-bit */
> + XLLSDMA_CR_INT_ON_END = (1 << 9), /* Interrupt-on-end */
> + XLLSDMA_CR_LD_IRQ_CNT = (1 << 8), /* Load IRQ_COUNT */
> + XLLSDMA_CR_IRQ_EN = (1 << 7), /* Master interrupt enable */
> + XLLSDMA_CR_IRQ_ERROR = (1 << 2), /* Error interrupt enable */
> + XLLSDMA_CR_IRQ_TIMEOUT = (1 << 1), /* Coalesce timeout interrupt enable */
> + XLLSDMA_CR_IRQ_THRESHOLD = (1 << 0), /* Coalesce threshold interrupt enable */
> +
> + XLLSDMA_CR_IRQ_ALL = XLLSDMA_CR_IRQ_EN | XLLSDMA_CR_IRQ_ERROR |
> + XLLSDMA_CR_IRQ_TIMEOUT | XLLSDMA_CR_IRQ_THRESHOLD,
> +
> + XLLSDMA_CR_IRQ_TIMEOUT_SH = 24,
> + XLLSDMA_CR_IRQ_THRESHOLD_SH = 16,
> + XLLSDMA_CR_MSB_ADDR_SH = 12,
> +
> + XLLSDMA_IRQ_WRQ_EMPTY = (1 << 14), /* Write Command Queue Empty (rx) */
> + XLLSDMA_IRQ_PLB_RD_ERROR = (1 << 4), /* PLB Read Error IRQ */
> + XLLSDMA_IRQ_PLB_WR_ERROR = (1 << 3), /* PLB Write Error IRQ */
> + XLLSDMA_IRQ_ERROR = (1 << 2), /* Error IRQ */
> + XLLSDMA_IRQ_TIMEOUT = (1 << 1), /* Coalesce timeout IRQ */
> + XLLSDMA_IRQ_THRESHOLD = (1 << 0), /* Coalesce threshold IRQ */
> +
> + XLLSDMA_IRQ_ALL_ERR = 0x1C, /* All error interrupt */
> + XLLSDMA_IRQ_ALL = 0x1F, /* All interrupt bits */
> + XLLSDMA_IRQ_ALL_DONE = 0x3, /* All work complete interrupt bits */
> +
> +
> +#define XLLSDMA_IRQ_COALESCE_COUNT(x) ((x >> 10) & 0xF)
> +#define XLLSDMA_IRQ_DELAY_COUNT(x) ((x >> 8) & 0x3)
> +
> + XLLSDMA_SR_ERR_TDESCR = (1 << 21), /* Tail descriptor pointer is invalid */
> + XLLSDMA_SR_ERR_CMPL = (1 << 20), /* Complete bit is set */
> + XLLSDMA_SR_ERR_BUFA = (1 << 19), /* Buffer address is invalid */
> + XLLSDMA_SR_ERR_NDESCR = (1 << 18), /* Next descriptor pointer is invalid */
> + XLLSDMA_SR_ERR_CDESCR = (1 << 17), /* Current descriptor pointer is invalid */
> + XLLSDMA_SR_ERR_BUSYWR = (1 << 16), /* Current descriptor modified */
> + XLLSDMA_SR_ERROR = (1 << 7), /* Error IRQ has occurred */
> + XLLSDMA_SR_IRQ_ON_END = (1 << 6), /* On-end IRQ has occurred */
> + XLLSDMA_SR_STOP_ON_END = (1 << 5), /* Stop on end has occurred */
> + XLLSDMA_SR_COMPLETED = (1 << 4), /* BD completed */
> + XLLSDMA_SR_SOP = (1 << 3), /* Current BD has SOP set */
> + XLLSDMA_SR_EOP = (1 << 2), /* Current BD has EOP set */
> + XLLSDMA_SR_ENGINE_BUSY = (1 << 1), /* Channel is busy */
> +
> +
> + XLLSDMA_DMACR_TX_PAUSE = (1 << 29), /* Pause TX channel */
> + XLLSDMA_DMACR_RX_PAUSE = (1 << 28), /* Pause RX channel */
> + XLLSDMA_DMACR_PLB_ERR_DIS = (1 << 5), /* Disable PLB error detection */
> + XLLSDMA_DMACR_RX_OVF_DIS = (1 << 4), /* Disable error on RX coalesce counter overflows */
> + XLLSDMA_DMACR_TX_OVF_DIS = (1 << 3), /* Disable error on TX coalesce counter overflows */
> + XLLSDMA_DMACR_TAIL_PTR_EN = (1 << 2), /* Enable use of tail pointer register */
> + XLLSDMA_DMACR_EN_ARB_HOLD = (1 << 1), /* Enable arbitration hold */
> + XLLSDMA_DMACR_RESET = (1 << 0), /* Reset both channels */
> +};
> +
> +static inline void xllsdma_write_cr(struct xllsdma_device *sdma, u32 value)
> +{
> + out_be32(sdma->ioaddr + XLLSDMA_DMACR, value);
> +}
> +
> +static inline u32 xllsdma_read_cr(struct xllsdma_device *sdma)
> +{
> + return in_be32(sdma->ioaddr + XLLSDMA_DMACR);
> +}
> +
> +static inline void xllsdma_tx_out32(struct xllsdma_device *sdma, int reg, u32 value)
> +{
> + out_be32(sdma->ioaddr + reg + XLLSDMA_TX_REGS, value);
> +}
> +
> +static inline u32 xllsdma_tx_in32(struct xllsdma_device *sdma, int reg)
> +{
> + return in_be32(sdma->ioaddr + reg + XLLSDMA_TX_REGS);
> +}
> +
> +static inline void xllsdma_rx_out32(struct xllsdma_device *sdma, int reg, u32 value)
> +{
> + out_be32(sdma->ioaddr + reg + XLLSDMA_RX_REGS, value);
> +}
> +
> +static inline u32 xllsdma_rx_in32(struct xllsdma_device *sdma, int reg)
> +{
> + return in_be32(sdma->ioaddr + reg + XLLSDMA_RX_REGS);
> +}
> +
> +void xllsdma_reset(struct xllsdma_device *sdma)
> +{
> + u32 rx_cr, tx_cr, rx_irq, tx_irq;
> +
> + unsigned long flags;
> + struct xllsdma_client *client, *tmp;
> +
> + DEFINE_XLLSDMA_COALESCE(coal);
> + spin_lock_irqsave(&sdma->lock, flags);
> +
> + xllsdma_write_cr(sdma, XLLSDMA_DMACR_RESET);
> +
> + while (xllsdma_read_cr(sdma) & XLLSDMA_DMACR_RESET)
> + udelay(100);
> +
> + rx_cr = xllsdma_rx_in32(sdma, XLLSDMA_CR);
> + tx_cr = xllsdma_tx_in32(sdma, XLLSDMA_CR);
> +
> + xllsdma_rx_out32(sdma, XLLSDMA_CR, rx_cr & ~XLLSDMA_CR_IRQ_ALL);
> + xllsdma_tx_out32(sdma, XLLSDMA_CR, tx_cr & ~XLLSDMA_CR_IRQ_ALL);
> +
> + rx_irq = xllsdma_rx_in32(sdma, XLLSDMA_IRQ);
> + tx_irq = xllsdma_tx_in32(sdma, XLLSDMA_IRQ);
> +
> + xllsdma_rx_out32(sdma, XLLSDMA_IRQ, rx_irq);
> + xllsdma_tx_out32(sdma, XLLSDMA_IRQ, tx_irq);
> +
> + xllsdma_write_cr(sdma, XLLSDMA_DMACR_TAIL_PTR_EN |
> + XLLSDMA_DMACR_RX_OVF_DIS | XLLSDMA_DMACR_TX_OVF_DIS);
> +
> + if (sdma->rx_irq != NO_IRQ) {
> + xllsdma_rx_out32(sdma, XLLSDMA_CR,
> + rx_cr | (XLLSDMA_CR_IRQ_ALL & ~XLLSDMA_CR_IRQ_EN));
> +
> + rx_cr = xllsdma_rx_in32(sdma, XLLSDMA_CR);
> + xllsdma_rx_out32(sdma, XLLSDMA_CR, rx_cr | XLLSDMA_CR_IRQ_EN);
> + }
> +
> + if (sdma->tx_irq != NO_IRQ) {
> + xllsdma_tx_out32(sdma, XLLSDMA_CR,
> + tx_cr | (XLLSDMA_CR_IRQ_ALL & ~XLLSDMA_CR_IRQ_EN));
> + tx_cr = xllsdma_tx_in32(sdma, XLLSDMA_CR);
> + xllsdma_tx_out32(sdma, XLLSDMA_CR, tx_cr | XLLSDMA_CR_IRQ_EN);
> + }
> +
> + spin_unlock_irqrestore(&sdma->lock, flags);
> +
> + list_for_each_entry_safe(client, tmp, &sdma->clients, item)
> + if (likely(client->reset))
> + client->reset(client->data);
> +
> + xllsdma_set_coalesce(sdma, &coal);
> +}
> +EXPORT_SYMBOL_GPL(xllsdma_reset);
> +
> +void xllsdma_tx_irq_enable(struct xllsdma_device *sdma)
> +{
> + u32 tx_cr;
> + unsigned long flags;
> +
> + BUG_ON(sdma->tx_irq == NO_IRQ);
> +
> + spin_lock_irqsave(&sdma->lock, flags);
> + tx_cr = xllsdma_tx_in32(sdma, XLLSDMA_CR);
> + xllsdma_tx_out32(sdma, XLLSDMA_CR, tx_cr | XLLSDMA_CR_IRQ_EN);
> + spin_unlock_irqrestore(&sdma->lock, flags);
> +}
> +EXPORT_SYMBOL_GPL(xllsdma_tx_irq_enable);
> +
> +void xllsdma_rx_irq_enable(struct xllsdma_device *sdma)
> +{
> + u32 rx_cr;
> + unsigned long flags;
> +
> + BUG_ON(sdma->rx_irq == NO_IRQ);
> +
> + spin_lock_irqsave(&sdma->lock, flags);
> + rx_cr = xllsdma_rx_in32(sdma, XLLSDMA_CR);
> + xllsdma_rx_out32(sdma, XLLSDMA_CR, rx_cr | XLLSDMA_CR_IRQ_EN);
> + spin_unlock_irqrestore(&sdma->lock, flags);
> +}
> +EXPORT_SYMBOL_GPL(xllsdma_rx_irq_enable);
> +
> +void xllsdma_tx_irq_disable(struct xllsdma_device *sdma)
> +{
> + u32 tx_cr;
> + unsigned long flags;
> +
> + spin_lock_irqsave(&sdma->lock, flags);
> + tx_cr = xllsdma_tx_in32(sdma, XLLSDMA_CR);
> + xllsdma_tx_out32(sdma, XLLSDMA_CR, tx_cr & ~XLLSDMA_CR_IRQ_EN);
> + spin_unlock_irqrestore(&sdma->lock, flags);
> +}
> +EXPORT_SYMBOL_GPL(xllsdma_tx_irq_disable);
> +
> +void xllsdma_rx_irq_disable(struct xllsdma_device *sdma)
> +{
> + u32 rx_cr;
> + unsigned long flags;
> +
> + spin_lock_irqsave(&sdma->lock, flags);
> + rx_cr = xllsdma_rx_in32(sdma, XLLSDMA_CR);
> + xllsdma_rx_out32(sdma, XLLSDMA_CR, rx_cr & ~XLLSDMA_CR_IRQ_EN);
> + spin_unlock_irqrestore(&sdma->lock, flags);
> +}
> +EXPORT_SYMBOL_GPL(xllsdma_rx_irq_disable);
> +
> +void xllsdma_tx_irq_ack(struct xllsdma_device *sdma)
> +{
> + u32 irq_stat;
> + unsigned long flags;
> +
> + spin_lock_irqsave(&sdma->lock, flags);
> + irq_stat = xllsdma_tx_in32(sdma, XLLSDMA_IRQ);
> + xllsdma_tx_out32(sdma, XLLSDMA_IRQ, irq_stat & XLLSDMA_IRQ_ALL_DONE);
> + spin_unlock_irqrestore(&sdma->lock, flags);
> +}
> +EXPORT_SYMBOL_GPL(xllsdma_tx_irq_ack);
> +
> +void xllsdma_rx_irq_ack(struct xllsdma_device *sdma)
> +{
> + u32 irq_stat;
> + unsigned long flags;
> +
> + spin_lock_irqsave(&sdma->lock, flags);
> + irq_stat = xllsdma_rx_in32(sdma, XLLSDMA_IRQ);
> + xllsdma_rx_out32(sdma, XLLSDMA_IRQ, irq_stat & XLLSDMA_IRQ_ALL_DONE);
> + spin_unlock_irqrestore(&sdma->lock, flags);
> +}
> +EXPORT_SYMBOL_GPL(xllsdma_rx_irq_ack);
> +
> +void xllsdma_pause(struct xllsdma_device *sdma)
> +{
> + u32 dmacr;
> + unsigned long flags;
> +
> + spin_lock_irqsave(&sdma->lock, flags);
> + dmacr = xllsdma_read_cr(sdma);
> + dmacr |= XLLSDMA_DMACR_TX_PAUSE | XLLSDMA_DMACR_RX_PAUSE;
> + xllsdma_write_cr(sdma, dmacr);
> + spin_unlock_irqrestore(&sdma->lock, flags);
> +}
> +EXPORT_SYMBOL_GPL(xllsdma_pause);
> +
> +void xllsdma_resume(struct xllsdma_device *sdma)
> +{
> + u32 dmacr;
> + unsigned long flags;
> +
> + spin_lock_irqsave(&sdma->lock, flags);
> + dmacr = xllsdma_read_cr(sdma);
> + dmacr &= ~(XLLSDMA_DMACR_TX_PAUSE | XLLSDMA_DMACR_RX_PAUSE);
> + xllsdma_write_cr(sdma, dmacr);
> + spin_unlock_irqrestore(&sdma->lock, flags);
> +}
> +EXPORT_SYMBOL_GPL(xllsdma_resume);
> +
> +int xllsdma_set_coalesce(struct xllsdma_device *sdma, struct xllsdma_coalesce *coal)
> +{
> + u32 tx_cr, rx_cr;
> + unsigned long flags;
> +
> + if (coal->tx_timeout > 255 ||
> + coal->rx_timeout > 255 ||
> + coal->tx_threshold > 255 ||
> + coal->rx_threshold > 255)
> + return -EINVAL;
> +
> + spin_lock_irqsave(&sdma->lock, flags);
> +
> + if (sdma->rx_irq != NO_IRQ) {
> + rx_cr = xllsdma_rx_in32(sdma, XLLSDMA_CR);
> +
> + if (coal->rx_timeout == 0) {
> + coal->rx_timeout = 1;
> + rx_cr &= ~XLLSDMA_CR_IRQ_TIMEOUT;
> + } else {
> + rx_cr |= XLLSDMA_CR_IRQ_TIMEOUT;
> + }
> +
> + rx_cr &= ~(XLLSDMA_CR_IRQ_THRESHOLD_MSK | XLLSDMA_CR_IRQ_TIMEOUT_SH);
> + rx_cr |= (coal->rx_threshold << XLLSDMA_CR_IRQ_THRESHOLD_SH)
> + & XLLSDMA_CR_IRQ_THRESHOLD_MSK;
> + rx_cr |= (coal->rx_timeout << XLLSDMA_CR_IRQ_TIMEOUT_SH)
> + & XLLSDMA_CR_IRQ_TIMEOUT_MSK;
> + rx_cr |= XLLSDMA_CR_LD_IRQ_CNT;
> +
> + xllsdma_rx_out32(sdma, XLLSDMA_CR, rx_cr);
> + }
> +
> + if (sdma->tx_irq != NO_IRQ) {
> + tx_cr = xllsdma_tx_in32(sdma, XLLSDMA_CR);
> +
> + if (coal->tx_timeout == 0) {
> + coal->tx_timeout = 1;
> + tx_cr &= ~XLLSDMA_CR_IRQ_TIMEOUT;
> + } else {
> + tx_cr |= XLLSDMA_CR_IRQ_TIMEOUT;
> + }
> +
> + tx_cr &= ~(XLLSDMA_CR_IRQ_THRESHOLD_MSK | XLLSDMA_CR_IRQ_TIMEOUT_SH);
> + tx_cr |= (coal->tx_threshold << XLLSDMA_CR_IRQ_THRESHOLD_SH)
> + & XLLSDMA_CR_IRQ_THRESHOLD_MSK;
> + tx_cr |= (coal->tx_timeout << XLLSDMA_CR_IRQ_TIMEOUT_SH)
> + & XLLSDMA_CR_IRQ_TIMEOUT_MSK;
> + tx_cr |= XLLSDMA_CR_LD_IRQ_CNT;
> +
> + xllsdma_tx_out32(sdma, XLLSDMA_CR, tx_cr);
> + }
> +
> + spin_unlock_irqrestore(&sdma->lock, flags);
> +
> + return 0;
> +}
> +EXPORT_SYMBOL_GPL(xllsdma_set_coalesce);
> +
> +int xllsdma_get_coalesce(struct xllsdma_device *sdma, struct xllsdma_coalesce *coal)
> +{
> + u32 tx_cr, rx_cr;
> + unsigned long flags;
> +
> + spin_lock_irqsave(&sdma->lock, flags);
> +
> + tx_cr = xllsdma_tx_in32(sdma, XLLSDMA_CR);
> + rx_cr = xllsdma_rx_in32(sdma, XLLSDMA_CR);
> +
> + coal->tx_threshold = (tx_cr & XLLSDMA_CR_IRQ_THRESHOLD_MSK)
> + >> XLLSDMA_CR_IRQ_THRESHOLD_SH;
> + coal->tx_timeout = (tx_cr & XLLSDMA_CR_IRQ_TIMEOUT_MSK)
> + >> XLLSDMA_CR_IRQ_TIMEOUT_SH;
> +
> + coal->rx_threshold = (rx_cr & XLLSDMA_CR_IRQ_THRESHOLD_MSK)
> + >> XLLSDMA_CR_IRQ_THRESHOLD_SH;
> + coal->rx_timeout = (rx_cr & XLLSDMA_CR_IRQ_TIMEOUT_MSK)
> + >> XLLSDMA_CR_IRQ_TIMEOUT_SH;
> +
> + if (!(tx_cr & XLLSDMA_CR_IRQ_TIMEOUT))
> + coal->tx_timeout = 0;
> +
> + if (!(rx_cr & XLLSDMA_CR_IRQ_TIMEOUT))
> + coal->rx_timeout = 0;
> +
> + spin_unlock_irqrestore(&sdma->lock, flags);
> +
> + return 0;
> +}
> +EXPORT_SYMBOL_GPL(xllsdma_get_coalesce);
> +
> +int xllsdma_tx_submit(struct xllsdma_device *sdma, dma_addr_t desc)
> +{
> + xllsdma_tx_out32(sdma, XLLSDMA_TDESCR, desc);
> + return 0;
> +}
> +EXPORT_SYMBOL_GPL(xllsdma_tx_submit);
Invariant return value can be dropped.
>
> +
> +int xllsdma_rx_submit(struct xllsdma_device *sdma, dma_addr_t desc)
> +{
> + xllsdma_rx_out32(sdma, XLLSDMA_TDESCR, desc);
> + return 0;
> +}
> +EXPORT_SYMBOL_GPL(xllsdma_rx_submit);
>
Invariant return value can be dropped.
> +
> +void xllsdma_tx_init(struct xllsdma_device *sdma, dma_addr_t desc)
> +{
> + xllsdma_tx_out32(sdma, XLLSDMA_CDESCR, desc);
> +}
> +EXPORT_SYMBOL_GPL(xllsdma_tx_init);
> +
> +void xllsdma_rx_init(struct xllsdma_device *sdma, dma_addr_t desc)
> +{
> + xllsdma_rx_out32(sdma, XLLSDMA_CDESCR, desc);
> +}
> +EXPORT_SYMBOL_GPL(xllsdma_rx_init);
> +
> +struct xllsdma_device *xllsdma_find_device(int phandle)
> +{
> + struct mpmc_device *mpmc;
> + struct xllsdma_device *sdma = NULL;
> + int found = 0;
> + mutex_lock(&mpmc_devs_lock);
> + list_for_each_entry(mpmc, &mpmc_devs, item) {
> + mutex_lock(&mpmc->devs_lock);
> + list_for_each_entry(sdma, &mpmc->xllsdma_devs, item) {
> + if (sdma->phandle == phandle) {
> + found = 1;
> + break;
> + }
> + }
> + mutex_unlock(&mpmc->devs_lock);
> + if (found)
> + break;
> + else
> + sdma = NULL;
> + }
> + mutex_unlock(&mpmc_devs_lock);
> + return sdma;
> +}
> +EXPORT_SYMBOL_GPL(xllsdma_find_device);
I'm still concerned that there is no concept of "allocating" or "reserving" a
channel. This seems to invite accidental concurrent use of a channel, if not in
the field, then during development.
> +
> +static irqreturn_t xllsdma_rx_intr(int irq, void *dev_id)
> +{
> + u32 irq_ack, status;
> + struct xllsdma_device *sdma = dev_id;
> + struct xllsdma_client *client, *tmp;
> +
> + /* Read pending interrupts */
> + status = xllsdma_rx_in32(sdma, XLLSDMA_IRQ);
> + irq_ack = status;
> + irq_ack &= sdma->rx_ack ? XLLSDMA_IRQ_ALL : XLLSDMA_IRQ_ALL_ERR;
> + xllsdma_rx_out32(sdma, XLLSDMA_IRQ, irq_ack);
> +
> + if (unlikely(status & XLLSDMA_IRQ_ALL_ERR)) {
> + dev_err(sdma->dev, "%s: error status: %08x\n", __func__,
> + status);
> + xllsdma_reset(sdma);
> + list_for_each_entry_safe(client, tmp, &sdma->clients, item)
> + if (likely(client->error))
> + client->error(client->data);
> + return IRQ_HANDLED;
> + }
> +
> + if (likely(status & XLLSDMA_IRQ_ALL_DONE)) {
> + list_for_each_entry_safe(client, tmp, &sdma->clients, item)
> + if (likely(client->rx_complete))
> + client->rx_complete(client->data);
> + }
> +
> + return IRQ_HANDLED;
> +}
> +
> +static irqreturn_t xllsdma_tx_intr(int irq, void *dev_id)
> +{
> + u32 irq_ack, status;
> + struct xllsdma_device *sdma = dev_id;
> + struct xllsdma_client *client, *tmp;
> +
> + /* Read pending interrupts */
> + status = xllsdma_tx_in32(sdma, XLLSDMA_IRQ);
> + irq_ack = status;
> + irq_ack &= sdma->tx_ack ? XLLSDMA_IRQ_ALL : XLLSDMA_IRQ_ALL_ERR;
> + xllsdma_tx_out32(sdma, XLLSDMA_IRQ, irq_ack);
> +
> + if (unlikely(status & XLLSDMA_IRQ_ALL_ERR)) {
> + dev_err(sdma->dev, "%s: error status: %08x\n", __func__,
> + status);
> + xllsdma_reset(sdma);
> + list_for_each_entry_safe(client, tmp, &sdma->clients, item)
> + if (likely(client->error))
> + client->error(client->data);
> + return IRQ_HANDLED;
> + }
> +
> + if (likely(status & XLLSDMA_IRQ_ALL_DONE)) {
> + list_for_each_entry_safe(client, tmp, &sdma->clients, item)
> + if (likely(client->tx_complete))
> + client->tx_complete(client->data);
> + }
> +
> + return IRQ_HANDLED;
> +}
> +
> +static void xllsdma_dev_register(struct mpmc_device *mpmc,
> + struct xllsdma_device *sdma)
> +{
> + mutex_lock(&mpmc->devs_lock);
> + list_add(&sdma->item, &mpmc->xllsdma_devs);
> + mutex_unlock(&mpmc->devs_lock);
> +}
> +
> +static void xllsdma_dev_unregister(struct xllsdma_device *sdma)
> +{
> + struct mpmc_device *mpmc = sdma->parent;
> +
> + mutex_lock(&mpmc->devs_lock);
> + list_del(&sdma->item);
> + mutex_unlock(&mpmc->devs_lock);
> +}
> +
> +static void xllsdma_cleanup(struct device *dev)
> +{
> + struct xllsdma_device *sdma = dev_get_drvdata(dev);
> +
> + if (sdma->tx_irq)
> + free_irq(sdma->tx_irq, sdma);
> +
> + if (sdma->rx_irq)
> + free_irq(sdma->rx_irq, sdma);
> +
> + if (sdma->memregion.start)
> + release_mem_region(sdma->memregion.start,
> + sdma->memregion.end - sdma->memregion.start + 1);
> +
> + if (sdma->ioaddr)
> + iounmap(sdma->ioaddr);
> +
> + xllsdma_dev_unregister(sdma);
> + kfree(sdma);
> + dev_set_drvdata(dev, NULL);
> +}
> +
> +static void mpmc_dev_register(struct mpmc_device *mpmc)
> +{
> + mutex_lock(&mpmc_devs_lock);
> + list_add_tail(&mpmc->item, &mpmc_devs);
> + mutex_unlock(&mpmc_devs_lock);
> +}
> +
> +static void mpmc_dev_unregister(struct mpmc_device *mpmc)
> +{
> + mutex_lock(&mpmc_devs_lock);
> + list_del(&mpmc->item);
> + mutex_unlock(&mpmc_devs_lock);
> +}
> +
> +static void mpmc_cleanup(struct device *dev)
> +{
> + struct mpmc_device *mpmc = dev_get_drvdata(dev);
> +
> + if (mpmc->registered)
> + mpmc_dev_unregister(mpmc);
> +
> + kfree(mpmc);
> + dev_set_drvdata(dev, NULL);
> +}
> +
> +static int __devinit xllsdma_init(struct device *dev, struct resource *rx_irq,
> + struct resource *tx_irq, struct resource *mem,
> + int phandle)
> +{
> + struct xllsdma_device *sdma;
> + struct mpmc_device *mpmc;
> +
> + resource_size_t region_size;
> + int res;
> +
> + mpmc = dev_get_drvdata(dev->parent);
> +
> + sdma = kzalloc(sizeof(struct xllsdma_device), GFP_KERNEL);
> + if (!sdma) {
> + dev_err(dev, "Cannot allocate SDMA device\n");
> + return -ENOMEM;
> + }
> + dev_set_drvdata(dev, sdma);
> + sdma->dev = dev;
> +
> + spin_lock_init(&sdma->lock);
> + INIT_LIST_HEAD(&sdma->clients);
> + mutex_init(&sdma->clients_lock);
> + sdma->parent = mpmc;
> + sdma->phandle = phandle;
> +
> + region_size = mem->end - mem->start + 1;
> + if (!request_mem_region(mem->start, region_size, DRV_NAME)) {
> + dev_err(dev, "I/O memory region at %p is busy\n",
> + (void *)mem->start);
> + return -EBUSY;
> + }
> + sdma->memregion = *mem;
> +
> + sdma->ioaddr = ioremap(mem->start, region_size);
> + if (!sdma->ioaddr) {
> + dev_err(dev, "Cannot ioremap() I/O memory %p\n",
> + (void *)mem->start);
> + return -ENOMEM;
> + }
> +
> + xllsdma_reset(sdma);
> +
> + sdma->rx_irq = NO_IRQ;
> + if (rx_irq) {
> + res = request_irq(rx_irq->start, xllsdma_rx_intr,
> + IRQF_SHARED, "SDMA RX", sdma);
> + if (res) {
> + dev_err(dev, "Could not allocate RX interrupt %d.\n",
> + rx_irq->start);
> + return res;
> + }
> + sdma->rx_irq = rx_irq->start;
> + }
> +
> + sdma->tx_irq = NO_IRQ;
> + if (tx_irq) {
> + res = request_irq(tx_irq->start, xllsdma_tx_intr,
> + IRQF_SHARED, "SDMA TX", sdma);
> + if (res) {
> + dev_err(dev, "Could not allocate TX interrupt %d.\n",
> + tx_irq->start);
> + return res;
> + }
> + sdma->tx_irq = tx_irq->start;
> + }
> +
> + sdma->rx_ack = 1;
> + sdma->tx_ack = 1;
> + xllsdma_dev_register(mpmc, sdma);
> +
> + return 0;
> +}
> +
> +static int __devinit mpmc_init(struct device *dev)
> +{
> + struct mpmc_device *mpmc;
> +
> + mpmc = kzalloc(sizeof(struct mpmc_device), GFP_KERNEL);
> +
> + if (!mpmc) {
> + dev_err(dev, "Cannot allocate MPMC device\n");
> + return -ENOMEM;
> + }
> +
> + dev_set_drvdata(dev, mpmc);
> +
> + INIT_LIST_HEAD(&mpmc->xllsdma_devs);
> + mutex_init(&mpmc->devs_lock);
> +
> + mpmc_dev_register(mpmc);
> + mpmc->registered = 1;
> +
> + return 0;
> +}
> +
> +#ifdef CONFIG_OF
> +static int xllsdma_of_remove(struct of_device *op)
> +{
> + xllsdma_cleanup(&op->dev);
> + return 0;
> +}
> +
> +/* Match table for of_platform binding */
> +static struct of_device_id xllsdma_of_match[] = {
> + { .compatible = "xlnx,ll-dma-1.00.a" },
> + {},
> +};
> +
> +static int __devinit xllsdma_of_probe(struct of_device *op,
> + const struct of_device_id *match)
> +{
> + const int *prop;
> + int phandle;
> + struct resource rx_irq, tx_irq, mem;
> + struct resource *tx_irq_res = NULL;
> + struct resource *rx_irq_res = NULL;
> + int res;
> +
> + res = of_address_to_resource(op->node, 0, &mem);
> + if (res) {
> + dev_err(&op->dev, "invalid address\n");
> + return res;
> + }
> +
> + /* IRQ */
> + res = of_irq_to_resource(op->node, 0, &rx_irq);
> + if (res != NO_IRQ)
> + rx_irq_res = &rx_irq;
> +
> + res = of_irq_to_resource(op->node, 1, &tx_irq);
> + if (res != NO_IRQ)
> + tx_irq_res = &tx_irq;
> +
> + prop = of_get_property(op->node, "linux,phandle", NULL);
> + phandle = (prop) ? *prop : -1;
> +
> + res = xllsdma_init(&op->dev, rx_irq_res, tx_irq_res, &mem, phandle);
> + if (res)
> + xllsdma_of_remove(op);
> +
> + return res;
> +}
> +
> +static struct of_platform_driver xllsdma_of_driver = {
> + .name = "xilinx-sdma",
> + .match_table = xllsdma_of_match,
> + .probe = xllsdma_of_probe,
> + .remove = xllsdma_of_remove,
> +};
> +
> +int __init xllsdma_of_init(void)
> +{
> + int ret;
> +
> + ret = of_register_platform_driver(&xllsdma_of_driver);
> + if (ret) {
> + of_unregister_platform_driver(&xllsdma_of_driver);
> + printk(KERN_ERR "registering driver failed: err=%i", ret);
> + return ret;
> + }
> +
> + return 0;
> +}
> +
> +void xllsdma_of_exit(void)
> +{
> + of_unregister_platform_driver(&xllsdma_of_driver);
> +}
> +
> +static int mpmc_of_remove(struct of_device *op)
> +{
> + struct device_node *node;
> + struct of_device *ofdev;
> +
> + for_each_child_of_node(op->node, node) {
> + ofdev = of_find_device_by_node(node);
> + of_device_unregister(ofdev);
> + of_device_free(ofdev);
> + }
> +
> + mpmc_cleanup(&op->dev);
> + return 0;
> +}
> +
> +static int __devinit mpmc_of_probe(struct of_device *op,
> + const struct of_device_id *match)
> +{
> + int err = mpmc_init(&op->dev);
> + if (err)
> + return err;
> +
> + of_platform_bus_probe(op->node, xllsdma_of_match, &op->dev);
> + return 0;
> +}
> +
> +static struct of_device_id __devinitdata mpmc_of_match[] = {
> + { .compatible = "xlnx,mpmc-4.01.a" },
> + { .compatible = "xlnx,mpmc-4.03.a" },
> + {},
> +};
> +
> +static struct of_platform_driver mpmc_of_driver = {
> + .name = "xilinx-mpmc",
> + .match_table = mpmc_of_match,
> + .probe = mpmc_of_probe,
> + .remove = mpmc_of_remove,
> +};
> +
> +int __init mpmc_of_init(void)
> +{
> + return of_register_platform_driver(&mpmc_of_driver);
> +}
> +
> +void mpmc_of_exit(void)
> +{
> + of_unregister_platform_driver(&mpmc_of_driver);
> +}
> +
> +subsys_initcall(mpmc_of_init);
> +subsys_initcall(xllsdma_of_init);
> +#else /* CONFIG_OF */
> +/*---------------------------------------------------------------------------
> + * Platform bus attachment
> + */
> +
> +static __devexit int xllsdma_plat_remove(struct platform_device *pdev)
> +{
> + xllsdma_cleanup(&pdev->dev);
> + return 0;
> +}
> +
> +static int __devinit xllsdma_plat_probe(struct platform_device *pdev)
> +{
> + struct resource *rx_irq, *tx_irq, *mem;
> + int err = 0;
> +
> + mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> + if (!mem) {
> + dev_err(&pdev->dev, "invalid address\n");
> + err = -EINVAL;
> + goto fail;
> + }
> +
> + /* RX interrupt is optional, and first */
> + rx_irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
> +
> + /* TX interrupt is optional, and second */
> + tx_irq = platform_get_resource(pdev, IORESOURCE_IRQ, 1);
> +
If it is impossible to create duplicate phandles in Device Tree,
there should be a check here that no device with pdev->id already exists
(i.e., it's NOT impossible with platform bus). It might be just as well to
put the check in xllsdma_init() since that's not a 'hot' code path.
> + err = xllsdma_init(&pdev->dev, rx_irq, tx_irq, mem, pdev->id);
> + if (err)
> + xllsdma_plat_remove(pdev);
> +fail:
> + return err;
> +}
> +
> +static struct platform_driver xllsdma_plat_driver = {
> + .probe = xllsdma_plat_probe,
> + .remove = __devexit_p(xllsdma_plat_remove),
> + .driver = {
> + .owner = THIS_MODULE,
> + .name = "xilinx-sdma",
> + },
> +};
> +
> +int __init xllsdma_plat_init(void)
> +{
> + int err = platform_driver_register(&xllsdma_plat_driver);
> + if (err) {
> + platform_driver_unregister(&xllsdma_plat_driver);
> + printk(KERN_ERR "registering driver failed: err=%i", err);
> + return err;
> + }
> +
> + return 0;
> +}
> +subsys_initcall(xllsdma_plat_init);
> +
> +void xllsdma_plat_exit(void)
> +{
> + platform_driver_unregister(&xllsdma_plat_driver);
> +}
> +
> +static int mpmc_plat_probe(struct platform_device *pdev)
> +{
> + return mpmc_init(&pdev->dev);
> +}
> +
> +static int __devexit mpmc_plat_remove(struct platform_device *pdev)
> +{
> + mpmc_cleanup(&pdev->dev);
> + return 0;
> +}
> +
> +static struct platform_driver mpmc_plat_driver = {
> + .probe = mpmc_plat_probe,
> + .remove = __devexit_p(mpmc_plat_remove),
> + .driver = {
> + .owner = THIS_MODULE,
> + .name = "xilinx-mpmc",
> + },
> +};
> +
> +int __init mpmc_plat_init(void)
> +{
> + return platform_driver_register(&mpmc_plat_driver);
> +}
> +subsys_initcall(mpmc_plat_init);
> +
> +void mpmc_plat_exit(void)
> +{
> + platform_driver_unregister(&mpmc_plat_driver);
> +}
> +#endif /* CONFIG_OF */
> diff -r baced9e29ab5 include/linux/xllsdma.h
> --- /dev/null Thu Jan 01 00:00:00 1970 +0000
> +++ b/include/linux/xllsdma.h Wed Apr 28 02:00:51 2010 +0400
> @@ -0,0 +1,187 @@
> +/*
> + * SDMA subsystem support for Xilinx MPMC.
> + *
> + * Author: Sergey Temerkhanov
> + *
> + * Copyright (c) 2008-2010 Cifronic ZAO
> + *
> + * This program is free software; you can redistribute it and/or modify it
> + * under the terms of the GNU General Public License as published by the
> + * Free Software Foundation; either version 2 of the License, or (at your
> + * option) any later version.
> + *
> + */
> +
> +#ifndef __XLLSDMA_H__
> +#define __XLLSDMA_H__
> +
> +#include <linux/types.h>
> +#include <linux/dma-mapping.h>
> +
> +#define XLLSDMA_ALIGNMENT 0x40
> +
> +struct xllsdma_desc {
> + __be32 next;
> + __be32 address;
> + __be32 length;
> + __be32 stat_ctl;
> + __be32 app1;
> + __be32 app2;
> + __be32 app3;
> + __be32 app4;
> + void *virt;
> + u32 flags;
> +} __attribute__((aligned(XLLSDMA_ALIGNMENT)));
'virt' and 'flags' are not used by this driver. Putting them in this structure,
and using this structure in the API, forces them on all clients, which can lead
to inefficiencies (this will certainly be true in the DMA engine driver, perhaps
others). I think a better choice would be to have the API use a structure without
these two fields. For the convenience of other clients you could define a
'superstructure' _not_ used in the API, like:
struct xllsdma_fancy_desc {
struct xllsdma_desc basic_desc;
void *virt;
u32 flags;
}
> +
> +
> +enum {
> + XLLSDMA_STSCTL_ERROR = (1 << 31), /* DMA error */
> + XLLSDMA_STSCTL_IOE = (1 << 30), /* Interrupt on end */
> + XLLSDMA_STSCTL_SOE = (1 << 29), /* Stop on end */
> + XLLSDMA_STSCTL_DONE = (1 << 28), /* DMA completed */
> + XLLSDMA_STSCTL_SOP = (1 << 27), /* Start of packet */
> + XLLSDMA_STSCTL_EOP = (1 << 26), /* End of packet */
> + XLLSDMA_STSCTL_BUSY = (1 << 25), /* DMA busy */
> + XLLSDMA_STSCTL_CSUM = (1 << 0), /* Checksum enable */
> +
> + XLLSDMA_STSCTL_MSK = (0xFF << 24), /*Status/control field */
> +};
The search-and-replace messed up your nice alignment.
> +
> +/* SDMA client operations */
> +struct xllsdma_client {
> + void *data;
> + void (*tx_complete) (void *data);
> + void (*rx_complete) (void *data);
> + void (*error) (void *data);
> + void (*reset) (void *data);
> + struct list_head item;
> +};
> +
> +struct xllsdma_coalesce {
> + int tx_threshold;
> + int tx_timeout;
> +
> + int rx_threshold;
> + int rx_timeout;
> +};
> +
> +#define DEFINE_XLLSDMA_COALESCE(x) struct xllsdma_coalesce x = { \
> + .tx_timeout = 0, \
> + .tx_threshold = 1, \
> + .rx_timeout = 0, \
> + .rx_threshold = 1, };
> +
> +struct mpmc_device {
> + void __iomem *ioaddr;
> +
> + struct resource memregion;
> + int irq;
> +
> + int registered;
> + struct list_head item;
> +
> + struct mutex devs_lock;
> + struct list_head xllsdma_devs;
> +};
> +
> +struct xllsdma_device {
> + struct device *dev;
> + void __iomem *ioaddr;
> + wait_queue_head_t wait;
> +
> + spinlock_t lock;
> +
> + struct resource memregion;
> + int rx_irq;
> + int tx_irq;
> + int rx_ack;
> + int tx_ack;
> + int phandle;
> +
> + int registered;
> + struct mpmc_device *parent;
> +
> + struct xllsdma_coalesce coal;
> + struct list_head item;
> +
> + struct mutex clients_lock;
> + struct list_head clients;
> +};
> +
> +static inline void xllsdma_add_client(struct xllsdma_device *sdma,
> + struct xllsdma_client *client)
> +{
> + mutex_lock(&sdma->clients_lock);
> + list_add(&client->item, &sdma->clients);
> + mutex_unlock(&sdma->clients_lock);
> +}
> +
> +static inline void xllsdma_del_client(struct xllsdma_device *sdma,
> + struct xllsdma_client *client)
> +{
> + mutex_lock(&sdma->clients_lock);
> + list_del(&client->item);
> + mutex_unlock(&sdma->clients_lock);
> +}
> +
> +struct xllsdma_device *xllsdma_find_device(int phandle);
> +void xllsdma_pause(struct xllsdma_device *sdma);
> +void xllsdma_resume(struct xllsdma_device *sdma);
> +void xllsdma_reset(struct xllsdma_device *sdma);
> +void xllsdma_rx_init(struct xllsdma_device *sdma, dma_addr_t desc);
> +void xllsdma_tx_init(struct xllsdma_device *sdma, dma_addr_t desc);
> +
> +int xllsdma_tx_submit(struct xllsdma_device *sdma, dma_addr_t desc);
> +int xllsdma_rx_submit(struct xllsdma_device *sdma, dma_addr_t desc);
> +
> +void xllsdma_tx_irq_enable(struct xllsdma_device *sdma);
> +void xllsdma_rx_irq_enable(struct xllsdma_device *sdma);
> +void xllsdma_tx_irq_disable(struct xllsdma_device *sdma);
> +void xllsdma_rx_irq_disable(struct xllsdma_device *sdma);
> +void xllsdma_tx_irq_ack(struct xllsdma_device *sdma);
> +void xllsdma_rx_irq_ack(struct xllsdma_device *sdma);
> +
> +int xllsdma_set_coalesce(struct xllsdma_device *sdma, struct xllsdma_coalesce *coal);
> +int xllsdma_get_coalesce(struct xllsdma_device *sdma, struct xllsdma_coalesce *coal);
> +
> +static inline int xllsdma_has_tx_irq(struct xllsdma_device *sdma)
> +{
> + return sdma->tx_irq != NO_IRQ;
> +}
> +
> +static inline int xllsdma_has_rx_irq(struct xllsdma_device *sdma)
> +{
> + return sdma->rx_irq != NO_IRQ;
> +}
> +
> +static inline int xllsdma_desc_busy(struct xllsdma_desc *desc)
> +{
> + return desc->stat_ctl & __constant_be32_to_cpu(XLLSDMA_STSCTL_BUSY);
> +}
> +
> +static inline int xllsdma_desc_done(struct xllsdma_desc *desc)
> +{
> + return desc->stat_ctl & __constant_be32_to_cpu(XLLSDMA_STSCTL_DONE);
> +}
> +
> +static inline int xllsdma_desc_sop(struct xllsdma_desc *desc)
> +{
> + return desc->stat_ctl & __constant_be32_to_cpu(XLLSDMA_STSCTL_SOP);
> +}
> +
> +static inline int xllsdma_desc_eop(struct xllsdma_desc *desc)
> +{
> + return desc->stat_ctl & __constant_be32_to_cpu(XLLSDMA_STSCTL_EOP);
> +}
> +
> +static inline void xllsdma_set_ack(struct xllsdma_device *sdma, int rx_ack,
> + int tx_ack)
> +{
> + unsigned long flags;
> + spin_lock_irqsave(&sdma->lock, flags);
> + sdma->rx_ack = rx_ack;
> + sdma->tx_ack = tx_ack;
> + spin_unlock_irqrestore(&sdma->lock, flags);
> +}
> +
> +#endif
------------------------------------------------------------------------
Steven J. Magnani "I claim this network for MARS!
www.digidescorp.com Earthling, return my space modulator!"
#include <standard.disclaimer>
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/