From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jeff Garzik Subject: Re: [PATCH] PXA DMA-capable PATA driver Date: Fri, 14 May 2010 18:03:45 -0400 Message-ID: <4BEDC8C1.30703@garzik.org> References: <1273460525-25662-1-git-send-email-marek.vasut@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from mail-gx0-f217.google.com ([209.85.217.217]:52576 "EHLO mail-gx0-f217.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754417Ab0ENWDs (ORCPT ); Fri, 14 May 2010 18:03:48 -0400 Received: by gxk9 with SMTP id 9so2003260gxk.8 for ; Fri, 14 May 2010 15:03:47 -0700 (PDT) In-Reply-To: <1273460525-25662-1-git-send-email-marek.vasut@gmail.com> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: Marek Vasut Cc: linux-ide@vger.kernel.org, linux-arm-kernel@lists.infradead.org, eric.y.miao@gmail.com, haojian.zhuang@gmail.com On 05/09/2010 11:02 PM, Marek Vasut wrote: > This patch adds a driver for a harddrive attached to PXA address and data bus. > Unlike pata_platform, this driver allows usage of PXA DMA controller, making the > transmission speed 3x higher. > > Signed-off-by: Marek Vasut > --- > arch/arm/mach-pxa/include/mach/pata_pxa.h | 33 +++ > drivers/ata/Kconfig | 11 + > drivers/ata/Makefile | 1 + > drivers/ata/pata_pxa.c | 383 +++++++++++++++++++++++++++++ > 4 files changed, 428 insertions(+), 0 deletions(-) > create mode 100644 arch/arm/mach-pxa/include/mach/pata_pxa.h > create mode 100644 drivers/ata/pata_pxa.c > > diff --git a/arch/arm/mach-pxa/include/mach/pata_pxa.h b/arch/arm/mach-pxa/include/mach/pata_pxa.h > new file mode 100644 > index 0000000..6cf7df1 > --- /dev/null > +++ b/arch/arm/mach-pxa/include/mach/pata_pxa.h > @@ -0,0 +1,33 @@ > +/* > + * Generic PXA PATA driver > + * > + * Copyright (C) 2010 Marek Vasut > + * > + * 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, or (at your option) > + * any later version. > + * > + * This program is distributed in the hope that it will be useful, > + * but WITHOUT ANY WARRANTY; without even the implied warranty of > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the > + * GNU General Public License for more details. > + * > + * You should have received a copy of the GNU General Public License > + * along with this program; see the file COPYING. If not, write to > + * the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. > + */ > + > +#ifndef __MACH_PATA_PXA_H__ > +#define __MACH_PATA_PXA_H__ > + > +struct pata_pxa_pdata { > + /* PXA DMA DREQ<0:2> pin */ > + uint32_t dma_dreq; > + /* Register shift */ > + uint32_t reg_shift; > + /* IRQ flags */ > + uint32_t irq_flags; > +}; > + > +#endif /* __MACH_PATA_PXA_H__ */ > diff --git a/drivers/ata/Kconfig b/drivers/ata/Kconfig > index 01c52c4..5cd3e8c 100644 > --- a/drivers/ata/Kconfig > +++ b/drivers/ata/Kconfig > @@ -684,6 +684,17 @@ config PATA_VIA > > If unsure, say N. > > +config PATA_PXA > + tristate "PXA DMA-capable PATA support" > + depends on ARCH_PXA > + help > + This option enables support for harddrive attached to PXA CPU's bus. > + > + NOTE: This driver utilizes PXA DMA controller, in case your hardware > + is not capable of doing MWDMA, use pata_platform instead. > + > + If unsure, say N. > + > config PATA_WINBOND > tristate "Winbond SL82C105 PATA support" > depends on PCI > diff --git a/drivers/ata/Makefile b/drivers/ata/Makefile > index fc936d4..5ecf45a 100644 > --- a/drivers/ata/Makefile > +++ b/drivers/ata/Makefile > @@ -79,6 +79,7 @@ obj-$(CONFIG_PATA_PLATFORM) += pata_platform.o > obj-$(CONFIG_PATA_AT91) += pata_at91.o > obj-$(CONFIG_PATA_OF_PLATFORM) += pata_of_platform.o > obj-$(CONFIG_PATA_ICSIDE) += pata_icside.o > +obj-$(CONFIG_PATA_PXA) += pata_pxa.o > # Should be last but two libata driver > obj-$(CONFIG_PATA_ACPI) += pata_acpi.o > # Should be last but one libata driver > diff --git a/drivers/ata/pata_pxa.c b/drivers/ata/pata_pxa.c > new file mode 100644 > index 0000000..66ab1ac > --- /dev/null > +++ b/drivers/ata/pata_pxa.c > @@ -0,0 +1,383 @@ > +/* > + * Generic PXA PATA driver > + * > + * Copyright (C) 2010 Marek Vasut > + * > + * 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, or (at your option) > + * any later version. > + * > + * This program is distributed in the hope that it will be useful, > + * but WITHOUT ANY WARRANTY; without even the implied warranty of > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the > + * GNU General Public License for more details. > + * > + * You should have received a copy of the GNU General Public License > + * along with this program; see the file COPYING. If not, write to > + * the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. > + */ > + > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > + > +#include > + > +#include > +#include > +#include > + > +#define DRV_NAME "pata_pxa" > +#define DRV_VERSION "0.1" > + > +struct pata_pxa_data { > + uint32_t dma_channel; > + struct pxa_dma_desc *dma_desc; > + dma_addr_t dma_desc_addr; > + uint32_t dma_desc_id; > + > + /* DMA IO physical address */ > + uint32_t dma_io_addr; > + /* PXA DREQ<0:2> pin selector */ > + uint32_t dma_dreq; > + > + struct completion dma_done; > +}; > + > +/* > + * Setup the DMA descriptors. The size is transfer capped at 4k per descriptor, > + * if the transfer is longer, it is split into multiple chained descriptors. > + */ > +static void pxa_load_dmac(struct scatterlist *sg, struct ata_queued_cmd *qc) > +{ > + struct pata_pxa_data *pd = qc->ap->private_data; > + > + uint32_t cpu_len, seg_len; > + dma_addr_t cpu_addr; > + > + cpu_addr = sg_dma_address(sg); > + cpu_len = sg_dma_len(sg); > + > + do { > + seg_len = (cpu_len> 0x1000) ? 0x1000 : cpu_len; > + > + pd->dma_desc[pd->dma_desc_id].ddadr = pd->dma_desc_addr + > + ((pd->dma_desc_id + 1) * sizeof(struct pxa_dma_desc)); > + > + pd->dma_desc[pd->dma_desc_id].dcmd = DCMD_BURST32 | DCMD_WIDTH2 | > + (DCMD_LENGTH& seg_len); > + > + if (qc->tf.flags& ATA_TFLAG_WRITE) { > + pd->dma_desc[pd->dma_desc_id].dsadr = cpu_addr; > + pd->dma_desc[pd->dma_desc_id].dtadr = pd->dma_io_addr; > + pd->dma_desc[pd->dma_desc_id].dcmd |= DCMD_INCSRCADDR | > + DCMD_FLOWTRG; > + } else { > + pd->dma_desc[pd->dma_desc_id].dsadr = pd->dma_io_addr; > + pd->dma_desc[pd->dma_desc_id].dtadr = cpu_addr; > + pd->dma_desc[pd->dma_desc_id].dcmd |= DCMD_INCTRGADDR | > + DCMD_FLOWSRC; > + } > + > + cpu_len -= seg_len; > + cpu_addr += seg_len; > + pd->dma_desc_id++; > + > + } while(cpu_len); > + > + /* Should not happen */ > + if (seg_len& 0x1f) > + DALGN |= (1<< pd->dma_dreq); > +} normally this is done in the fill_sg step, part of qc_prep. is that doable for pata_pxa? > +static void pxa_bmdma_setup(struct ata_queued_cmd *qc) > +{ > + struct pata_pxa_data *pd = qc->ap->private_data; > + int si = 0; > + struct scatterlist *sg; > + > + pd->dma_desc_id = 0; > + > + DCSR(pd->dma_channel) = 0; > + DALGN&= ~(1<< pd->dma_dreq); > + > + for_each_sg(qc->sg, sg, qc->n_elem, si) > + pxa_load_dmac(sg, qc); > + > + pd->dma_desc[pd->dma_desc_id - 1].ddadr = DDADR_STOP; > + > + /* Fire IRQ only at the end of last block */ > + pd->dma_desc[pd->dma_desc_id - 1].dcmd |= DCMD_ENDIRQEN; > + > + DDADR(pd->dma_channel) = pd->dma_desc_addr; > + DRCMR(pd->dma_dreq) = DRCMR_MAPVLD | pd->dma_channel; > + qc->ap->ops->sff_exec_command(qc->ap,&qc->tf); > +} > + > +/* > + * Execute the DMA transfer. > + */ > +static void pxa_bmdma_start(struct ata_queued_cmd *qc) > +{ > + struct pata_pxa_data *pd = qc->ap->private_data; > + init_completion(&pd->dma_done); > + DCSR(pd->dma_channel) = DCSR_RUN; > +} > + > +/* > + * Wait until the DMA transfer completes, then stop the DMA controller. > + */ > +static void pxa_bmdma_stop(struct ata_queued_cmd *qc) > +{ > + struct pata_pxa_data *pd = qc->ap->private_data; > + > + if (DCSR(pd->dma_channel)& DCSR_RUN) > + if (wait_for_completion_timeout(&pd->dma_done, HZ)) > + BUG(); > + > + DCSR(pd->dma_channel) = 0; a little bit more description than BUG() would be useful. BUG() is a bit unfriendly and vague way to report errors. > + * Read DMA status. The bmdma_stop() will take care of properly finishing the > + * DMA transfer so we always have DMA-complete interrupt here. > + */ > +static unsigned char pxa_bmdma_status(struct ata_port *ap) > +{ > + return ATA_DMA_INTR; > +} are you able to detect bus error? > + */ > +static void pxa_irq_clear(struct ata_port *ap) > +{ > +} > + > +/* > + * Check for ATAPI DMA. ATAPI DMA is unsupported by this driver. It's still > + * unclear why ATAPI has DMA issues. > + */ > +static int pxa_check_atapi_dma(struct ata_queued_cmd *qc) > +{ > + return -EOPNOTSUPP; > +} This is a bug. Return 1 or 0. This statement actually tells libata to -enable- DMA! From mboxrd@z Thu Jan 1 00:00:00 1970 From: jeff@garzik.org (Jeff Garzik) Date: Fri, 14 May 2010 18:03:45 -0400 Subject: [PATCH] PXA DMA-capable PATA driver In-Reply-To: <1273460525-25662-1-git-send-email-marek.vasut@gmail.com> References: <1273460525-25662-1-git-send-email-marek.vasut@gmail.com> Message-ID: <4BEDC8C1.30703@garzik.org> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 05/09/2010 11:02 PM, Marek Vasut wrote: > This patch adds a driver for a harddrive attached to PXA address and data bus. > Unlike pata_platform, this driver allows usage of PXA DMA controller, making the > transmission speed 3x higher. > > Signed-off-by: Marek Vasut > --- > arch/arm/mach-pxa/include/mach/pata_pxa.h | 33 +++ > drivers/ata/Kconfig | 11 + > drivers/ata/Makefile | 1 + > drivers/ata/pata_pxa.c | 383 +++++++++++++++++++++++++++++ > 4 files changed, 428 insertions(+), 0 deletions(-) > create mode 100644 arch/arm/mach-pxa/include/mach/pata_pxa.h > create mode 100644 drivers/ata/pata_pxa.c > > diff --git a/arch/arm/mach-pxa/include/mach/pata_pxa.h b/arch/arm/mach-pxa/include/mach/pata_pxa.h > new file mode 100644 > index 0000000..6cf7df1 > --- /dev/null > +++ b/arch/arm/mach-pxa/include/mach/pata_pxa.h > @@ -0,0 +1,33 @@ > +/* > + * Generic PXA PATA driver > + * > + * Copyright (C) 2010 Marek Vasut > + * > + * 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, or (at your option) > + * any later version. > + * > + * This program is distributed in the hope that it will be useful, > + * but WITHOUT ANY WARRANTY; without even the implied warranty of > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the > + * GNU General Public License for more details. > + * > + * You should have received a copy of the GNU General Public License > + * along with this program; see the file COPYING. If not, write to > + * the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. > + */ > + > +#ifndef __MACH_PATA_PXA_H__ > +#define __MACH_PATA_PXA_H__ > + > +struct pata_pxa_pdata { > + /* PXA DMA DREQ<0:2> pin */ > + uint32_t dma_dreq; > + /* Register shift */ > + uint32_t reg_shift; > + /* IRQ flags */ > + uint32_t irq_flags; > +}; > + > +#endif /* __MACH_PATA_PXA_H__ */ > diff --git a/drivers/ata/Kconfig b/drivers/ata/Kconfig > index 01c52c4..5cd3e8c 100644 > --- a/drivers/ata/Kconfig > +++ b/drivers/ata/Kconfig > @@ -684,6 +684,17 @@ config PATA_VIA > > If unsure, say N. > > +config PATA_PXA > + tristate "PXA DMA-capable PATA support" > + depends on ARCH_PXA > + help > + This option enables support for harddrive attached to PXA CPU's bus. > + > + NOTE: This driver utilizes PXA DMA controller, in case your hardware > + is not capable of doing MWDMA, use pata_platform instead. > + > + If unsure, say N. > + > config PATA_WINBOND > tristate "Winbond SL82C105 PATA support" > depends on PCI > diff --git a/drivers/ata/Makefile b/drivers/ata/Makefile > index fc936d4..5ecf45a 100644 > --- a/drivers/ata/Makefile > +++ b/drivers/ata/Makefile > @@ -79,6 +79,7 @@ obj-$(CONFIG_PATA_PLATFORM) += pata_platform.o > obj-$(CONFIG_PATA_AT91) += pata_at91.o > obj-$(CONFIG_PATA_OF_PLATFORM) += pata_of_platform.o > obj-$(CONFIG_PATA_ICSIDE) += pata_icside.o > +obj-$(CONFIG_PATA_PXA) += pata_pxa.o > # Should be last but two libata driver > obj-$(CONFIG_PATA_ACPI) += pata_acpi.o > # Should be last but one libata driver > diff --git a/drivers/ata/pata_pxa.c b/drivers/ata/pata_pxa.c > new file mode 100644 > index 0000000..66ab1ac > --- /dev/null > +++ b/drivers/ata/pata_pxa.c > @@ -0,0 +1,383 @@ > +/* > + * Generic PXA PATA driver > + * > + * Copyright (C) 2010 Marek Vasut > + * > + * 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, or (at your option) > + * any later version. > + * > + * This program is distributed in the hope that it will be useful, > + * but WITHOUT ANY WARRANTY; without even the implied warranty of > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the > + * GNU General Public License for more details. > + * > + * You should have received a copy of the GNU General Public License > + * along with this program; see the file COPYING. If not, write to > + * the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. > + */ > + > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > + > +#include > + > +#include > +#include > +#include > + > +#define DRV_NAME "pata_pxa" > +#define DRV_VERSION "0.1" > + > +struct pata_pxa_data { > + uint32_t dma_channel; > + struct pxa_dma_desc *dma_desc; > + dma_addr_t dma_desc_addr; > + uint32_t dma_desc_id; > + > + /* DMA IO physical address */ > + uint32_t dma_io_addr; > + /* PXA DREQ<0:2> pin selector */ > + uint32_t dma_dreq; > + > + struct completion dma_done; > +}; > + > +/* > + * Setup the DMA descriptors. The size is transfer capped at 4k per descriptor, > + * if the transfer is longer, it is split into multiple chained descriptors. > + */ > +static void pxa_load_dmac(struct scatterlist *sg, struct ata_queued_cmd *qc) > +{ > + struct pata_pxa_data *pd = qc->ap->private_data; > + > + uint32_t cpu_len, seg_len; > + dma_addr_t cpu_addr; > + > + cpu_addr = sg_dma_address(sg); > + cpu_len = sg_dma_len(sg); > + > + do { > + seg_len = (cpu_len> 0x1000) ? 0x1000 : cpu_len; > + > + pd->dma_desc[pd->dma_desc_id].ddadr = pd->dma_desc_addr + > + ((pd->dma_desc_id + 1) * sizeof(struct pxa_dma_desc)); > + > + pd->dma_desc[pd->dma_desc_id].dcmd = DCMD_BURST32 | DCMD_WIDTH2 | > + (DCMD_LENGTH& seg_len); > + > + if (qc->tf.flags& ATA_TFLAG_WRITE) { > + pd->dma_desc[pd->dma_desc_id].dsadr = cpu_addr; > + pd->dma_desc[pd->dma_desc_id].dtadr = pd->dma_io_addr; > + pd->dma_desc[pd->dma_desc_id].dcmd |= DCMD_INCSRCADDR | > + DCMD_FLOWTRG; > + } else { > + pd->dma_desc[pd->dma_desc_id].dsadr = pd->dma_io_addr; > + pd->dma_desc[pd->dma_desc_id].dtadr = cpu_addr; > + pd->dma_desc[pd->dma_desc_id].dcmd |= DCMD_INCTRGADDR | > + DCMD_FLOWSRC; > + } > + > + cpu_len -= seg_len; > + cpu_addr += seg_len; > + pd->dma_desc_id++; > + > + } while(cpu_len); > + > + /* Should not happen */ > + if (seg_len& 0x1f) > + DALGN |= (1<< pd->dma_dreq); > +} normally this is done in the fill_sg step, part of qc_prep. is that doable for pata_pxa? > +static void pxa_bmdma_setup(struct ata_queued_cmd *qc) > +{ > + struct pata_pxa_data *pd = qc->ap->private_data; > + int si = 0; > + struct scatterlist *sg; > + > + pd->dma_desc_id = 0; > + > + DCSR(pd->dma_channel) = 0; > + DALGN&= ~(1<< pd->dma_dreq); > + > + for_each_sg(qc->sg, sg, qc->n_elem, si) > + pxa_load_dmac(sg, qc); > + > + pd->dma_desc[pd->dma_desc_id - 1].ddadr = DDADR_STOP; > + > + /* Fire IRQ only at the end of last block */ > + pd->dma_desc[pd->dma_desc_id - 1].dcmd |= DCMD_ENDIRQEN; > + > + DDADR(pd->dma_channel) = pd->dma_desc_addr; > + DRCMR(pd->dma_dreq) = DRCMR_MAPVLD | pd->dma_channel; > + qc->ap->ops->sff_exec_command(qc->ap,&qc->tf); > +} > + > +/* > + * Execute the DMA transfer. > + */ > +static void pxa_bmdma_start(struct ata_queued_cmd *qc) > +{ > + struct pata_pxa_data *pd = qc->ap->private_data; > + init_completion(&pd->dma_done); > + DCSR(pd->dma_channel) = DCSR_RUN; > +} > + > +/* > + * Wait until the DMA transfer completes, then stop the DMA controller. > + */ > +static void pxa_bmdma_stop(struct ata_queued_cmd *qc) > +{ > + struct pata_pxa_data *pd = qc->ap->private_data; > + > + if (DCSR(pd->dma_channel)& DCSR_RUN) > + if (wait_for_completion_timeout(&pd->dma_done, HZ)) > + BUG(); > + > + DCSR(pd->dma_channel) = 0; a little bit more description than BUG() would be useful. BUG() is a bit unfriendly and vague way to report errors. > + * Read DMA status. The bmdma_stop() will take care of properly finishing the > + * DMA transfer so we always have DMA-complete interrupt here. > + */ > +static unsigned char pxa_bmdma_status(struct ata_port *ap) > +{ > + return ATA_DMA_INTR; > +} are you able to detect bus error? > + */ > +static void pxa_irq_clear(struct ata_port *ap) > +{ > +} > + > +/* > + * Check for ATAPI DMA. ATAPI DMA is unsupported by this driver. It's still > + * unclear why ATAPI has DMA issues. > + */ > +static int pxa_check_atapi_dma(struct ata_queued_cmd *qc) > +{ > + return -EOPNOTSUPP; > +} This is a bug. Return 1 or 0. This statement actually tells libata to -enable- DMA!