* [RFC 0/4] dmaengine: Slave DMA interface and example users
@ 2007-11-23 12:20 Haavard Skinnemoen
2007-11-23 12:20 ` [RFC 1/4] dmaengine: Add slave DMA interface Haavard Skinnemoen
0 siblings, 1 reply; 11+ messages in thread
From: Haavard Skinnemoen @ 2007-11-23 12:20 UTC (permalink / raw)
To: linux-kernel
Cc: Shannon Nelson, Dan Williams, David Brownell, kernel,
linux-arm-kernel, Haavard Skinnemoen
This patch series adds the necessary interfaces to the DMA Engine
framework to use functionality found on most embedded DMA controllers:
DMA from and to I/O registers with hardware handshaking.
In this context, hardware hanshaking means that the peripheral that
owns the I/O registers in question is able to tell the DMA controller
when more data is available for reading, or when there is room for
more data to be written. This usually happens internally on the chip,
but these signals may also be exported outside the chip for things
like IDE DMA, etc.
I'd really like some feedback on the first patch in the series,
particularly from people using other platforms than AVR32 and people
who use or want to use the DW DMAC controller for other things than
what the Atmel-provided drivers do. The three other patches in the
series are provided mostly for context, although I do want to get them
merged into mainline eventually. This should happen after the basic
interfaces have been properly worked out though.
I've tested everything together and it seems to work most of the time;
I can insert an MMC card and mount a partition with an ext3 filesystem
on it, but I get some ext3 errors from time to time, so there are
still some issues to be worked out.
Haavard
Haavard Skinnemoen (4):
dmaengine: Add slave DMA interface
dmaengine: Make DMA Engine menu visible for AVR32 users
dmaengine: Driver for the Synopsys DesignWare DMA controller
Atmel MCI: Driver for Atmel on-chip MMC controllers
arch/avr32/boards/atngw100/setup.c | 6 +
arch/avr32/boards/atstk1000/atstk1002.c | 3 +
arch/avr32/mach-at32ap/at32ap7000.c | 60 +-
drivers/dma/Kconfig | 11 +-
drivers/dma/Makefile | 1 +
drivers/dma/dmaengine.c | 6 +
drivers/dma/dw_dmac.c | 1180 ++++++++++++++++++++++++++++
drivers/dma/dw_dmac.h | 257 ++++++
drivers/mmc/host/Kconfig | 10 +
drivers/mmc/host/Makefile | 1 +
drivers/mmc/host/atmel-mci.c | 1170 +++++++++++++++++++++++++++
drivers/mmc/host/atmel-mci.h | 192 +++++
include/asm-avr32/arch-at32ap/at32ap7000.h | 16 +
include/asm-avr32/arch-at32ap/board.h | 10 +-
include/linux/dmaengine.h | 55 ++-
15 files changed, 2957 insertions(+), 21 deletions(-)
create mode 100644 drivers/dma/dw_dmac.c
create mode 100644 drivers/dma/dw_dmac.h
create mode 100644 drivers/mmc/host/atmel-mci.c
create mode 100644 drivers/mmc/host/atmel-mci.h
^ permalink raw reply [flat|nested] 11+ messages in thread
* [RFC 1/4] dmaengine: Add slave DMA interface
2007-11-23 12:20 [RFC 0/4] dmaengine: Slave DMA interface and example users Haavard Skinnemoen
@ 2007-11-23 12:20 ` Haavard Skinnemoen
2007-11-23 12:20 ` [RFC 2/4] dmaengine: Make DMA Engine menu visible for AVR32 users Haavard Skinnemoen
2007-12-03 19:20 ` [RFC 1/4] dmaengine: Add slave DMA interface Dan Williams
0 siblings, 2 replies; 11+ messages in thread
From: Haavard Skinnemoen @ 2007-11-23 12:20 UTC (permalink / raw)
To: linux-kernel
Cc: Shannon Nelson, Dan Williams, David Brownell, kernel,
linux-arm-kernel, Haavard Skinnemoen
Add a new struct dma_slave_descriptor which extends the standard
dma_async_tx_descriptor with a few members that are needed for doing
DMA from/to peripherals with hardware handshaking (aka slave DMA.)
Add new operations to struct dma_device for creating such descriptors,
for setting up the controller to do slave DMA for a given device, and
for terminating all pending transfers. The latter is needed because
there may be errors outside the scope of the DMA Engine framework that
requires DMA operations to be terminated prematurely.
Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
---
drivers/dma/dmaengine.c | 6 +++++
include/linux/dmaengine.h | 55 ++++++++++++++++++++++++++++++++++++++++++++-
2 files changed, 60 insertions(+), 1 deletions(-)
diff --git a/drivers/dma/dmaengine.c b/drivers/dma/dmaengine.c
index ec7e871..3d17918 100644
--- a/drivers/dma/dmaengine.c
+++ b/drivers/dma/dmaengine.c
@@ -362,6 +362,12 @@ int dma_async_device_register(struct dma_device *device)
!device->device_prep_dma_memset);
BUG_ON(dma_has_cap(DMA_ZERO_SUM, device->cap_mask) &&
!device->device_prep_dma_interrupt);
+ BUG_ON(dma_has_cap(DMA_SLAVE, device->cap_mask) &&
+ !device->device_set_slave);
+ BUG_ON(dma_has_cap(DMA_SLAVE, device->cap_mask) &&
+ !device->device_prep_slave);
+ BUG_ON(dma_has_cap(DMA_SLAVE, device->cap_mask) &&
+ !device->device_terminate_all);
BUG_ON(!device->device_alloc_chan_resources);
BUG_ON(!device->device_free_chan_resources);
diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h
index 55c9a69..e81189f 100644
--- a/include/linux/dmaengine.h
+++ b/include/linux/dmaengine.h
@@ -89,10 +89,33 @@ enum dma_transaction_type {
DMA_MEMSET,
DMA_MEMCPY_CRC32C,
DMA_INTERRUPT,
+ DMA_SLAVE,
};
/* last transaction type for creation of the capabilities mask */
-#define DMA_TX_TYPE_END (DMA_INTERRUPT + 1)
+#define DMA_TX_TYPE_END (DMA_SLAVE + 1)
+
+/**
+ * enum dma_slave_direction - direction of a DMA slave transfer
+ * @DMA_SLAVE_TO_MEMORY: Transfer data from peripheral to memory
+ * @DMA_SLAVE_FROM_MEMORY: Transfer data from memory to peripheral
+ */
+enum dma_slave_direction {
+ DMA_SLAVE_TO_MEMORY,
+ DMA_SLAVE_FROM_MEMORY,
+};
+
+/**
+ * enum dma_slave_width - DMA slave register access width.
+ * @DMA_SLAVE_WIDTH_8BIT: Do 8-bit slave register accesses
+ * @DMA_SLAVE_WIDTH_16BIT: Do 16-bit slave register accesses
+ * @DMA_SLAVE_WIDTH_32BIT: Do 32-bit slave register accesses
+ */
+enum dma_slave_width {
+ DMA_SLAVE_WIDTH_8BIT,
+ DMA_SLAVE_WIDTH_16BIT,
+ DMA_SLAVE_WIDTH_32BIT,
+};
/**
* dma_cap_mask_t - capabilities bitmap modeled after cpumask_t.
@@ -240,6 +263,25 @@ struct dma_async_tx_descriptor {
};
/**
+ * struct dma_slave_descriptor - extended DMA descriptor for slave DMA
+ * @async_tx: async transaction descriptor
+ * @slave_set_direction: set the direction of the slave DMA
+ * transaction in the hardware descriptor
+ * @slave_set_width: set the slave register access width in the
+ * hardware descriptor
+ * @client_node: for use by the client, for example when operating on
+ * scatterlists.
+ */
+struct dma_slave_descriptor {
+ struct dma_async_tx_descriptor txd;
+ void (*slave_set_direction)(struct dma_slave_descriptor *desc,
+ enum dma_slave_direction direction);
+ void (*slave_set_width)(struct dma_slave_descriptor *desc,
+ enum dma_slave_width width);
+ struct list_head client_node;
+};
+
+/**
* struct dma_device - info on the entity supplying DMA services
* @chancnt: how many DMA channels are supported
* @channels: the list of struct dma_chan
@@ -258,6 +300,10 @@ struct dma_async_tx_descriptor {
* @device_prep_dma_zero_sum: prepares a zero_sum operation
* @device_prep_dma_memset: prepares a memset operation
* @device_prep_dma_interrupt: prepares an end of chain interrupt operation
+ * @device_set_slave: set up a channel to do slave DMA for a given
+ * peripheral
+ * @device_prep_slave: prepares a slave dma operation
+ * @device_terminate_all: terminate all pending operations
* @device_dependency_added: async_tx notifies the channel about new deps
* @device_issue_pending: push pending transactions to hardware
*/
@@ -291,6 +337,13 @@ struct dma_device {
struct dma_async_tx_descriptor *(*device_prep_dma_interrupt)(
struct dma_chan *chan);
+ void (*device_set_slave)(struct dma_chan *chan,
+ dma_addr_t rx_reg, unsigned int rx_hs_id,
+ dma_addr_t tx_reg, unsigned int tx_hs_id);
+ struct dma_slave_descriptor *(*device_prep_slave)(
+ struct dma_chan *chan, size_t len, int int_en);
+ void (*device_terminate_all)(struct dma_chan *chan);
+
void (*device_dependency_added)(struct dma_chan *chan);
enum dma_status (*device_is_tx_complete)(struct dma_chan *chan,
dma_cookie_t cookie, dma_cookie_t *last,
--
1.5.3.4
^ permalink raw reply related [flat|nested] 11+ messages in thread
* [RFC 2/4] dmaengine: Make DMA Engine menu visible for AVR32 users
2007-11-23 12:20 ` [RFC 1/4] dmaengine: Add slave DMA interface Haavard Skinnemoen
@ 2007-11-23 12:20 ` Haavard Skinnemoen
2007-11-23 12:20 ` [RFC 3/4] dmaengine: Driver for the Synopsys DesignWare DMA controller Haavard Skinnemoen
2007-12-03 19:20 ` [RFC 1/4] dmaengine: Add slave DMA interface Dan Williams
1 sibling, 1 reply; 11+ messages in thread
From: Haavard Skinnemoen @ 2007-11-23 12:20 UTC (permalink / raw)
To: linux-kernel
Cc: Shannon Nelson, Dan Williams, David Brownell, kernel,
linux-arm-kernel, Haavard Skinnemoen
Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
---
drivers/dma/Kconfig | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)
diff --git a/drivers/dma/Kconfig b/drivers/dma/Kconfig
index 1db5499..9bcc392 100644
--- a/drivers/dma/Kconfig
+++ b/drivers/dma/Kconfig
@@ -4,7 +4,7 @@
menuconfig DMADEVICES
bool "DMA Engine support"
- depends on (PCI && X86) || ARCH_IOP32X || ARCH_IOP33X || ARCH_IOP13XX
+ depends on (PCI && X86) || ARCH_IOP32X || ARCH_IOP33X || ARCH_IOP13XX || AVR32
help
DMA engines can do asynchronous data transfers without
involving the host CPU. This can be used to offload memory
--
1.5.3.4
^ permalink raw reply related [flat|nested] 11+ messages in thread
* [RFC 3/4] dmaengine: Driver for the Synopsys DesignWare DMA controller
2007-11-23 12:20 ` [RFC 2/4] dmaengine: Make DMA Engine menu visible for AVR32 users Haavard Skinnemoen
@ 2007-11-23 12:20 ` Haavard Skinnemoen
2007-11-23 12:20 ` [RFC 4/4] Atmel MCI: Driver for Atmel on-chip MMC controllers Haavard Skinnemoen
0 siblings, 1 reply; 11+ messages in thread
From: Haavard Skinnemoen @ 2007-11-23 12:20 UTC (permalink / raw)
To: linux-kernel
Cc: Shannon Nelson, Dan Williams, David Brownell, kernel,
linux-arm-kernel, Haavard Skinnemoen
This adds a driver for the Synopsys DesignWare DMA controller (aka
DMACA on AVR32 systems.) This DMA controller can be found integrated
on the AT32AP7000 chip and is primarily meant for peripheral DMA
transfer, but can also be used for memory-to-memory transfers.
The dmatest client shows no problems, but the performance is not as
good as it should be yet -- iperf shows a slight slowdown when
enabling TCP receive copy offload. This is probably because the
controller is set up to always do byte transfers; I'll try to optimize
this, but if someone can tell me if there any guaranteed alignment
requirements for the users of the DMA engine API, that would help a
lot.
This patch is based on a driver from David Brownell which was based on
an older version of the DMA Engine framework. It also implements the
proposed extensions to the DMA Engine API for slave DMA operations.
Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
Changes since v1:
* Implement DMA slave operations
* Set DWC_MAX_LEN to a more sane number
* Get rid of the dummy descriptors
* Fix DWC_CTLL_SRC_WIDTH() definition (wrong start bit)
---
arch/avr32/mach-at32ap/at32ap7000.c | 29 +-
drivers/dma/Kconfig | 9 +
drivers/dma/Makefile | 1 +
drivers/dma/dw_dmac.c | 1180 ++++++++++++++++++++++++++++
drivers/dma/dw_dmac.h | 257 ++++++
include/asm-avr32/arch-at32ap/at32ap7000.h | 16 +
6 files changed, 1479 insertions(+), 13 deletions(-)
create mode 100644 drivers/dma/dw_dmac.c
create mode 100644 drivers/dma/dw_dmac.h
diff --git a/arch/avr32/mach-at32ap/at32ap7000.c b/arch/avr32/mach-at32ap/at32ap7000.c
index 7c4388f..1759f0d 100644
--- a/arch/avr32/mach-at32ap/at32ap7000.c
+++ b/arch/avr32/mach-at32ap/at32ap7000.c
@@ -450,6 +450,20 @@ static void __init genclk_init_parent(struct clk *clk)
clk->parent = parent;
}
+/* REVISIT we may want a real struct for this driver's platform data,
+ * but for now we'll only use it to pass the number of DMA channels
+ * configured into this instance. Also, most platform data here ought
+ * to be declared as "const" (not just this) ...
+ */
+static unsigned dw_dmac0_data = 3;
+
+static struct resource dw_dmac0_resource[] = {
+ PBMEM(0xff200000),
+ IRQ(2),
+};
+DEFINE_DEV_DATA(dw_dmac, 0);
+DEV_CLK(hclk, dw_dmac0, hsb, 10);
+
/* --------------------------------------------------------------------
* System peripherals
* -------------------------------------------------------------------- */
@@ -556,17 +570,6 @@ static struct clk pico_clk = {
.users = 1,
};
-static struct resource dmaca0_resource[] = {
- {
- .start = 0xff200000,
- .end = 0xff20ffff,
- .flags = IORESOURCE_MEM,
- },
- IRQ(2),
-};
-DEFINE_DEV(dmaca, 0);
-DEV_CLK(hclk, dmaca0, hsb, 10);
-
/* --------------------------------------------------------------------
* HMATRIX
* -------------------------------------------------------------------- */
@@ -666,7 +669,7 @@ void __init at32_add_system_devices(void)
platform_device_register(&at32_eic0_device);
platform_device_register(&smc0_device);
platform_device_register(&pdc_device);
- platform_device_register(&dmaca0_device);
+ platform_device_register(&dw_dmac0_device);
platform_device_register(&at32_systc0_device);
@@ -1627,7 +1630,7 @@ struct clk *at32_clock_list[] = {
&smc0_mck,
&pdc_hclk,
&pdc_pclk,
- &dmaca0_hclk,
+ &dw_dmac0_hclk,
&pico_clk,
&pio0_mck,
&pio1_mck,
diff --git a/drivers/dma/Kconfig b/drivers/dma/Kconfig
index 9bcc392..b67126f 100644
--- a/drivers/dma/Kconfig
+++ b/drivers/dma/Kconfig
@@ -36,6 +36,15 @@ config INTEL_IOP_ADMA
help
Enable support for the Intel(R) IOP Series RAID engines.
+config DW_DMAC
+ tristate "Synopsys DesignWare AHB DMA support"
+ depends on AVR32
+ select DMA_ENGINE
+ default y if CPU_AT32AP7000
+ help
+ Support the Synopsys DesignWare AHB DMA controller. This
+ can be integrated in chips such as the Atmel AT32ap7000.
+
config DMA_ENGINE
bool
diff --git a/drivers/dma/Makefile b/drivers/dma/Makefile
index b152cd8..c9e35a8 100644
--- a/drivers/dma/Makefile
+++ b/drivers/dma/Makefile
@@ -1,5 +1,6 @@
obj-$(CONFIG_DMA_ENGINE) += dmaengine.o
obj-$(CONFIG_NET_DMA) += iovlock.o
obj-$(CONFIG_INTEL_IOATDMA) += ioatdma.o
+obj-$(CONFIG_DW_DMAC) += dw_dmac.o
ioatdma-objs := ioat.o ioat_dma.o ioat_dca.o
obj-$(CONFIG_INTEL_IOP_ADMA) += iop-adma.o
diff --git a/drivers/dma/dw_dmac.c b/drivers/dma/dw_dmac.c
new file mode 100644
index 0000000..e425c3c
--- /dev/null
+++ b/drivers/dma/dw_dmac.c
@@ -0,0 +1,1180 @@
+/*
+ * Driver for the Synopsys DesignWare DMA Controller (aka DMACA on
+ * AVR32 systems.)
+ *
+ * Copyright (C) 2007 Atmel Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#define DEBUG
+
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/dmaengine.h>
+#include <linux/dma-mapping.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/mm.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+
+
+/* NOTE: DMS+SMS could be system-specific... */
+#define DWC_DEFAULT_CTLLO (DWC_CTLL_DST_MSIZE(4) \
+ | DWC_CTLL_SRC_MSIZE(4) \
+ | DWC_CTLL_DMS(0) \
+ | DWC_CTLL_SMS(1) \
+ | DWC_CTLL_LLP_D_EN \
+ | DWC_CTLL_LLP_S_EN)
+
+/*
+ * This is configuration-dependent and is usually a funny size like
+ * 4095. Let's round it down to the nearest power of two.
+ */
+#define DWC_MAX_LEN 2048
+
+/*
+ * This supports the Synopsis "DesignWare AHB Central DMA Controller",
+ * (DW_ahb_dmac) which is used with various AMBA 2.0 systems (not all
+ * of which use ARM any more). See the "Databook" from Synopsis for
+ * information beyond what licensees probably provide.
+ *
+ * This "DMA Engine" framework is currently only a memcpy accelerator,
+ * so the **PRIMARY FUNCTIONALITY** of this controller is not available:
+ * hardware-synchronized DMA to/from external hardware or integrated
+ * peripherals (such as an MMC/SD controller or audio interface).
+ *
+ * The driver has currently been tested only with the Atmel AT32AP7000,
+ * which appears to be configured without writeback ... contrary to docs,
+ * unless there's a bug in dma-coherent memory allocation.
+ */
+
+#define USE_DMA_POOL
+#undef USE_FREELIST
+
+#ifdef USE_DMA_POOL
+#include <linux/dmapool.h>
+#else
+#include <linux/slab.h>
+#endif
+
+#include "dw_dmac.h"
+
+/*----------------------------------------------------------------------*/
+
+#define NR_DESCS_PER_CHANNEL 8
+
+/* Because we're not relying on writeback from the controller (it may not
+ * even be configured into the core!) we don't need to use dma_pool. These
+ * descriptors -- and associated data -- are cacheable. We do need to make
+ * sure their dcache entries are written back before handing them off to
+ * the controller, though.
+ */
+
+#ifdef USE_FREELIST
+#define FREECNT 10 /* for fastpath allocations */
+#endif
+
+static struct dw_lli *
+dwc_lli_alloc(struct dw_dma_chan *dwc, gfp_t flags)
+{
+ struct dw_lli *lli;
+
+#ifdef USE_DMA_POOL
+ dma_addr_t phys;
+
+ lli = dma_pool_alloc(dwc->lli_pool, flags, &phys);
+ if (likely(lli))
+ lli->phys = phys;
+#else
+ lli = kmem_cache_alloc(dwc->lli_pool, flags);
+ if (unlikely(!lli))
+ return NULL;
+ lli->phys = dma_map_single(dwc->dev, lli,
+ sizeof *lli, DMA_TO_DEVICE);
+#endif
+
+ return lli;
+}
+
+static inline void
+dwc_lli_free(struct dw_dma_chan *dwc, struct dw_lli *lli)
+{
+#ifdef USE_DMA_POOL
+ dma_pool_free(dwc->lli_pool, lli, lli->phys);
+#else
+ dma_unmap_single(dwc->dev, lli->phys, sizeof *lli, DMA_TO_DEVICE);
+ kmem_cache_free(dwc->lli_pool, lli);
+#endif
+}
+
+static inline void
+dwc_lli_sync_for_device(struct dw_dma_chan *dwc, struct dw_lli *lli)
+{
+#ifndef USE_DMA_POOL
+ dma_sync_single_for_device(dwc->dev, lli->phys,
+ sizeof(struct dw_lli), DMA_TO_DEVICE);
+#endif
+}
+
+static inline struct dw_lli *
+dwc_lli_get(struct dw_dma_chan *dwc, gfp_t flags)
+{
+ struct dw_lli *lli;
+
+#ifdef USE_FREELIST
+ lli = dwc->free;
+
+ if (lli && FREECNT) {
+ dwc->free = lli->next;
+ dwc->freecnt--;
+ } else
+#endif
+ lli = dwc_lli_alloc(dwc, flags);
+
+ return lli;
+}
+
+static inline void
+dwc_lli_put(struct dw_dma_chan *dwc, struct dw_lli *lli)
+{
+#ifdef USE_FREELIST
+ if (dwc->freecnt < FREECNT) {
+ lli->ctllo = lli->ctlhi = 0;
+ lli->next = dwc->free;
+ dwc->free = lli;
+ dwc->freecnt++;
+ } else
+#endif
+ dwc_lli_free(dwc, lli);
+}
+
+static struct dw_desc *dwc_desc_get(struct dw_dma_chan *dwc)
+{
+ struct dw_desc *desc, *_desc;
+ struct dw_desc *ret = NULL;
+
+ spin_lock_bh(&dwc->lock);
+ list_for_each_entry_safe(desc, _desc, &dwc->free_list, desc_node) {
+ if (desc->slave.txd.ack) {
+ list_del(&desc->desc_node);
+ desc->slave.txd.ack = 0;
+ ret = desc;
+ break;
+ }
+ }
+ spin_unlock_bh(&dwc->lock);
+
+ return ret;
+}
+
+static void dwc_desc_put(struct dw_dma_chan *dwc, struct dw_desc *desc)
+{
+ spin_lock_bh(&dwc->lock);
+ list_add_tail(&desc->desc_node, &dwc->free_list);
+ spin_unlock_bh(&dwc->lock);
+}
+
+/* Called with dwc->lock held and bh disabled */
+static dma_cookie_t
+dwc_assign_cookie(struct dw_dma_chan *dwc, struct dw_desc *desc)
+{
+ dma_cookie_t cookie = dwc->chan.cookie;
+
+ if (++cookie < 0)
+ cookie = 1;
+
+ dwc->chan.cookie = cookie;
+ desc->slave.txd.cookie = cookie;
+
+ return cookie;
+}
+
+/*----------------------------------------------------------------------*/
+
+/* Called with dwc->lock held and bh disabled */
+static void dwc_dostart(struct dw_dma_chan *dwc, struct dw_lli *first)
+{
+ struct dw_dma *dw = to_dw_dma(dwc->chan.device);
+
+ if (dma_readl(dw, CH_EN) & dwc->mask) {
+ dev_err(&dwc->chan.dev,
+ "BUG: Attempted to start non-idle channel\n");
+ dev_err(&dwc->chan.dev, " new: %p last_lli: %p\n",
+ first, dwc->last_lli);
+ dev_err(&dwc->chan.dev,
+ " first_queued: %p last_queued: %p\n",
+ dwc->first_queued, dwc->last_queued);
+ dev_err(&dwc->chan.dev,
+ " LLP: 0x%x CTL: 0x%x:%08x\n",
+ channel_readl(dwc, LLP),
+ channel_readl(dwc, CTL_HI),
+ channel_readl(dwc, CTL_LO));
+
+ /* The tasklet will hopefully advance the queue... */
+ return;
+ }
+
+ /* ASSERT: channel is idle */
+
+ channel_writel(dwc, LLP, first->phys);
+ channel_writel(dwc, CTL_LO,
+ DWC_CTLL_LLP_D_EN | DWC_CTLL_LLP_S_EN);
+ channel_writel(dwc, CTL_HI, 0);
+ channel_set_bit(dw, CH_EN, dwc->mask);
+}
+
+/*----------------------------------------------------------------------*/
+
+/*
+ * Move descriptors that have been queued up because the DMA
+ * controller was busy at the time of submission, to the "active"
+ * list. The caller must make sure that the DMA controller is
+ * kickstarted if necessary.
+ *
+ * Called with dwc->lock held and bh disabled.
+ */
+static void dwc_submit_queue(struct dw_dma_chan *dwc)
+{
+ dwc->last_lli = dwc->last_queued;
+ list_splice_init(&dwc->queue, dwc->active_list.prev);
+ dwc->first_queued = dwc->last_queued = NULL;
+}
+
+static void
+dwc_descriptor_complete(struct dw_dma_chan *dwc, struct dw_desc *desc)
+{
+ struct dw_lli *lli;
+
+ dev_vdbg(&dwc->chan.dev, "descriptor %u complete\n",
+ desc->slave.txd.cookie);
+
+ dwc->completed = desc->slave.txd.cookie;
+ for (lli = desc->first_lli; lli; lli = lli->next)
+ dwc_lli_put(dwc, lli);
+
+ desc->first_lli = NULL;
+ list_move(&desc->desc_node, &dwc->free_list);
+
+ /*
+ * The API requires that no submissions are done from a
+ * callback, so we don't need to drop the lock here
+ */
+ if (desc->slave.txd.callback)
+ desc->slave.txd.callback(desc->slave.txd.callback_param);
+}
+
+static void dwc_complete_all(struct dw_dma *dw, struct dw_dma_chan *dwc)
+{
+ struct dw_desc *desc, *_desc;
+ LIST_HEAD(list);
+
+ /*
+ * Submit queued descriptors ASAP, i.e. before we go through
+ * the completed ones.
+ */
+ list_splice_init(&dwc->active_list, &list);
+
+ if (dma_readl(dw, CH_EN) & dwc->mask) {
+ dev_err(&dwc->chan.dev,
+ "BUG: XFER bit set, but channel not idle!\n");
+
+ /* Try to continue after resetting the channel... */
+ channel_clear_bit(dw, CH_EN, dwc->mask);
+ while (dma_readl(dw, CH_EN) & dwc->mask)
+ cpu_relax();
+ }
+
+ dwc->last_lli = NULL;
+ if (dwc->first_queued) {
+ dwc_dostart(dwc, dwc->first_queued);
+ dwc_submit_queue(dwc);
+ }
+
+ list_for_each_entry_safe(desc, _desc, &list, desc_node)
+ dwc_descriptor_complete(dwc, desc);
+}
+
+static void dwc_scan_descriptors(struct dw_dma *dw, struct dw_dma_chan *dwc)
+{
+ dma_addr_t llp;
+ struct dw_desc *desc, *_desc;
+ struct dw_lli *lli, *next;
+ u32 status_xfer;
+
+ /*
+ * Clear block interrupt flag before scanning so that we don't
+ * miss any, and read LLP before RAW_XFER to ensure it is
+ * valid if we decide to scan the list.
+ */
+ dma_writel(dw, CLEAR_BLOCK, dwc->mask);
+ llp = channel_readl(dwc, LLP);
+ status_xfer = dma_readl(dw, RAW_XFER);
+
+ if (status_xfer & dwc->mask) {
+ /* Everything we've submitted is done */
+ dma_writel(dw, CLEAR_XFER, dwc->mask);
+ dwc_complete_all(dw, dwc);
+ return;
+ }
+
+ dev_vdbg(&dwc->chan.dev, "scan_descriptors: llp=0x%x\n", llp);
+
+ list_for_each_entry_safe(desc, _desc, &dwc->active_list, desc_node) {
+ for (lli = desc->first_lli ; lli; lli = next) {
+ next = lli->next;
+
+ dev_vdbg(&dwc->chan.dev, " lli 0x%x done?\n",
+ lli->phys);
+ /*
+ * The last descriptor can't be done because
+ * the controller isn't idle.
+ */
+ if (!next || next->phys == llp)
+ return;
+
+ /* Last LLI in a this descriptor? */
+ if (lli->last)
+ break;
+ }
+
+ dwc_descriptor_complete(dwc, desc);
+ }
+
+ dev_err(&dwc->chan.dev,
+ "BUG: All descriptors done, but channel not idle!\n");
+
+ /* Try to continue after resetting the channel... */
+ channel_clear_bit(dw, CH_EN, dwc->mask);
+ while (dma_readl(dw, CH_EN) & dwc->mask)
+ cpu_relax();
+
+ dwc->last_lli = NULL;
+ if (dwc->first_queued) {
+ dwc_dostart(dwc, dwc->first_queued);
+ dwc_submit_queue(dwc);
+ }
+}
+
+static void dwc_handle_error(struct dw_dma *dw, struct dw_dma_chan *dwc)
+{
+ struct dw_desc *bad_desc;
+ struct dw_desc *next_desc;
+ struct dw_lli *lli;
+
+ dwc_scan_descriptors(dw, dwc);
+
+ /*
+ * The descriptor currently at the head of the active list is
+ * borked. Since we don't have any way to report errors, we'll
+ * just have to scream loudly and try to carry on.
+ */
+ bad_desc = list_entry(dwc->active_list.next,
+ struct dw_desc, desc_node);
+ list_del_init(&bad_desc->desc_node);
+ if (dwc->first_queued)
+ dwc_submit_queue(dwc);
+
+ /* Clear the error flag and try to restart the controller */
+ dma_writel(dw, CLEAR_ERROR, dwc->mask);
+ if (!list_empty(&dwc->active_list)) {
+ next_desc = list_entry(dwc->active_list.next,
+ struct dw_desc, desc_node);
+ dwc_dostart(dwc, next_desc->first_lli);
+ }
+
+ /*
+ * KERN_CRITICAL may seem harsh, but since this only happens
+ * when someone submits a bad physical address in a
+ * descriptor, we should consider ourselves lucky that the
+ * controller flagged an error instead of scribbling over
+ * random memory locations.
+ */
+ dev_printk(KERN_CRIT, &dwc->chan.dev,
+ "Bad descriptor submitted for DMA!\n");
+ dev_printk(KERN_CRIT, &dwc->chan.dev,
+ " cookie: %d\n", bad_desc->slave.txd.cookie);
+ for (lli = bad_desc->first_lli; lli; lli = lli->next)
+ dev_printk(KERN_CRIT, &dwc->chan.dev,
+ " LLI: s/0x%x d/0x%x l/0x%x c/0x%x:%x\n",
+ lli->sar, lli->dar, lli->llp,
+ lli->ctlhi, lli->ctllo);
+
+ /* Pretend the descriptor completed successfully */
+ dwc_descriptor_complete(dwc, bad_desc);
+}
+
+static void dw_dma_tasklet(unsigned long data)
+{
+ struct dw_dma *dw = (struct dw_dma *)data;
+ struct dw_dma_chan *dwc;
+ u32 status_block;
+ u32 status_xfer;
+ u32 status_err;
+ int i;
+
+ status_block = dma_readl(dw, RAW_BLOCK);
+ status_xfer = dma_readl(dw, RAW_BLOCK);
+ status_err = dma_readl(dw, RAW_ERROR);
+
+ dev_dbg(dw->dma.dev, "tasklet: status_block=%x status_err=%x\n",
+ status_block, status_err);
+
+ for (i = 0; i < NDMA; i++) {
+ dwc = &dw->chan[i];
+ spin_lock(&dwc->lock);
+ if (status_err & (1 << i))
+ dwc_handle_error(dw, dwc);
+ else if ((status_block | status_xfer) & (1 << i))
+ dwc_scan_descriptors(dw, dwc);
+ spin_unlock(&dwc->lock);
+ }
+
+ /*
+ * Re-enable interrupts. Block Complete interrupts are only
+ * enabled if the INT_EN bit in the descriptor is set. This
+ * will trigger a scan before the whole list is done.
+ */
+ channel_set_bit(dw, MASK_XFER, (1 << NDMA) - 1);
+ channel_set_bit(dw, MASK_BLOCK, (1 << NDMA) - 1);
+ channel_set_bit(dw, MASK_ERROR, (1 << NDMA) - 1);
+}
+
+static irqreturn_t dw_dma_interrupt(int irq, void *dev_id)
+{
+ struct dw_dma *dw = dev_id;
+ u32 status;
+
+ dev_vdbg(dw->dma.dev, "interrupt: status=0x%x\n",
+ dma_readl(dw, STATUS_INT));
+
+ /*
+ * Just disable the interrupts. We'll turn them back on in the
+ * softirq handler.
+ */
+ channel_clear_bit(dw, MASK_XFER, (1 << NDMA) - 1);
+ channel_clear_bit(dw, MASK_BLOCK, (1 << NDMA) - 1);
+ channel_clear_bit(dw, MASK_ERROR, (1 << NDMA) - 1);
+
+ status = dma_readl(dw, STATUS_INT);
+ if (status) {
+ dev_err(dw->dma.dev,
+ "BUG: Unexpected interrupts pending: 0x%x\n",
+ status);
+
+ /* Try to recover */
+ channel_clear_bit(dw, MASK_XFER, (1 << 8) - 1);
+ channel_clear_bit(dw, MASK_BLOCK, (1 << 8) - 1);
+ channel_clear_bit(dw, MASK_SRC_TRAN, (1 << 8) - 1);
+ channel_clear_bit(dw, MASK_DST_TRAN, (1 << 8) - 1);
+ channel_clear_bit(dw, MASK_ERROR, (1 << 8) - 1);
+ }
+
+ tasklet_schedule(&dw->tasklet);
+
+ return IRQ_HANDLED;
+}
+
+/*----------------------------------------------------------------------*/
+
+static dma_cookie_t dwc_tx_submit(struct dma_async_tx_descriptor *tx)
+{
+ struct dw_desc *desc = txd_to_dw_desc(tx);
+ struct dw_dma_chan *dwc = to_dw_dma_chan(tx->chan);
+ struct dw_lli *lli;
+ dma_cookie_t cookie;
+
+ /* Make sure all descriptors are written to RAM */
+ for (lli = desc->first_lli; lli; lli = lli->next) {
+ dev_vdbg(&dwc->chan.dev,
+ "tx_submit: %x: s/%x d/%x p/%x h/%x l/%x\n",
+ lli->phys, lli->sar, lli->dar, lli->llp,
+ lli->ctlhi, lli->ctllo);
+ dwc_lli_sync_for_device(dwc, lli);
+ }
+
+ spin_lock_bh(&dwc->lock);
+ cookie = dwc_assign_cookie(dwc, desc);
+
+ /*
+ * REVISIT: We should attempt to chain as many descriptors as
+ * possible, perhaps even appending to those already submitted
+ * for DMA. But this is hard to do in a race-free manner.
+ */
+ if (dwc->last_queued || dwc->last_lli) {
+ dev_vdbg(&tx->chan->dev, "tx_submit: queued %u\n",
+ desc->slave.txd.cookie);
+
+ list_add_tail(&desc->desc_node, &dwc->queue);
+ dwc->last_queued = desc->last_lli;
+ if (!dwc->first_queued)
+ dwc->first_queued = desc->first_lli;
+ } else {
+ dev_vdbg(&tx->chan->dev, "tx_submit: started %u\n",
+ desc->slave.txd.cookie);
+
+ dwc_dostart(dwc, desc->first_lli);
+ list_add_tail(&desc->desc_node, &dwc->active_list);
+ dwc->last_lli = desc->last_lli;
+ }
+
+ spin_unlock_bh(&dwc->lock);
+
+ return cookie;
+}
+
+static void dwc_tx_set_dest(dma_addr_t addr,
+ struct dma_async_tx_descriptor *tx, int index)
+{
+ /* FIXME: What does "index" mean? */
+ struct dw_desc *desc = txd_to_dw_desc(tx);
+ struct dw_lli *lli;
+
+ for (lli = desc->first_lli; lli; lli = lli->next) {
+ lli->dar = addr;
+ addr += DWC_MAX_LEN;
+ }
+}
+
+static void dwc_tx_set_src(dma_addr_t addr,
+ struct dma_async_tx_descriptor *tx, int index)
+{
+ /* FIXME: What does "index" mean? */
+ struct dw_desc *desc = txd_to_dw_desc(tx);
+ struct dw_lli *lli;
+
+ for (lli = desc->first_lli; lli; lli = lli->next) {
+ lli->sar = addr;
+ addr += DWC_MAX_LEN;
+ }
+}
+
+static void dwc_slave_set_direction(struct dma_slave_descriptor *sd,
+ enum dma_slave_direction direction)
+{
+ struct dw_dma_chan *dwc = to_dw_dma_chan(sd->txd.chan);
+ struct dw_desc *desc = sd_to_dw_desc(sd);
+ struct dw_lli *lli;
+
+ for (lli = desc->first_lli; lli; lli = lli->next) {
+ switch (direction) {
+ case DMA_SLAVE_TO_MEMORY:
+ lli->sar = dwc->slave_rx_reg;
+ lli->ctllo = (lli->ctllo
+ & (DWC_CTLL_INT_EN
+ | DWC_CTLL_DST_WIDTH(3)
+ | DWC_CTLL_SRC_WIDTH(3)
+ | DWC_CTLL_DST_MSIZE(7)
+ | DWC_CTLL_SRC_MSIZE(7)
+ | DWC_CTLL_DMS(3)
+ | DWC_CTLL_SMS(3)
+ | DWC_CTLL_LLP_D_EN
+ | DWC_CTLL_LLP_S_EN))
+ | DWC_CTLL_DST_INC
+ | DWC_CTLL_SRC_FIX
+ | DWC_CTLL_FC_P2M;
+ break;
+
+ case DMA_SLAVE_FROM_MEMORY:
+ lli->dar = dwc->slave_tx_reg;
+ lli->ctllo = (lli->ctllo
+ & (DWC_CTLL_INT_EN
+ | DWC_CTLL_DST_WIDTH(3)
+ | DWC_CTLL_SRC_WIDTH(3)
+ | DWC_CTLL_DST_MSIZE(7)
+ | DWC_CTLL_SRC_MSIZE(7)
+ | DWC_CTLL_DMS(3)
+ | DWC_CTLL_SMS(3)
+ | DWC_CTLL_LLP_D_EN
+ | DWC_CTLL_LLP_S_EN))
+ | DWC_CTLL_DST_FIX
+ | DWC_CTLL_SRC_INC
+ | DWC_CTLL_FC_M2P;
+ break;
+ }
+ }
+}
+
+static void dwc_slave_set_width(struct dma_slave_descriptor *sd,
+ enum dma_slave_width width)
+{
+ struct dw_desc *desc = sd_to_dw_desc(sd);
+ struct dw_lli *lli;
+
+ /*
+ * REVISIT: We're assuming the memory address and length are
+ * aligned to a multiple of 'width' too.
+ *
+ * Also, things will break if this function is called more
+ * than once after preparing the descriptor initially.
+ */
+ for (lli = desc->first_lli; lli; lli = lli->next) {
+ lli->ctlhi >>= width;
+ lli->ctllo = (lli->ctllo & ~(DWC_CTLL_DST_WIDTH(7)
+ | DWC_CTLL_SRC_WIDTH(7)))
+ | DWC_CTLL_DST_WIDTH(width)
+ | DWC_CTLL_SRC_WIDTH(width);
+ }
+}
+
+static struct dw_desc *dwc_prep_descriptor(struct dw_dma_chan *dwc,
+ u32 ctllo, size_t len, int int_en)
+{
+ struct dma_chan *chan = &dwc->chan;
+ struct dw_desc *desc;
+ struct dw_lli *prev, *lli;
+
+ if (unlikely(!len))
+ return NULL;
+
+ desc = dwc_desc_get(dwc);
+ if (!desc)
+ return NULL;
+
+ dev_vdbg(&chan->dev, " got descriptor %p\n", desc);
+
+ /*
+ * Use block chaining, and "transfer type 10" with source and
+ * destination addresses updated through LLP. Terminate using
+ * a dummy descriptor with invalid LLP.
+ *
+ * IMPORTANT: here we assume the core is configured with each
+ * channel supporting dma descriptor lists!
+ */
+ prev = NULL;
+ while (len) {
+ size_t max_len = DWC_MAX_LEN;
+ size_t block_len;
+
+ lli = dwc_lli_get(dwc, GFP_ATOMIC);
+ if (!lli)
+ goto err_lli_get;
+
+ block_len = min(len, max_len);
+
+ if (!prev) {
+ desc->first_lli = lli;
+ } else {
+ prev->last = 0;
+ prev->llp = lli->phys;
+ prev->next = lli;
+ }
+ lli->ctllo = ctllo;
+ lli->ctlhi = block_len;
+
+ len -= block_len;
+ prev = lli;
+
+ dev_vdbg(&chan->dev, " lli %p: len %zu phys 0x%x\n",
+ lli, block_len, lli->phys);
+ }
+
+ if (int_en)
+ /* Trigger interrupt after last block */
+ prev->ctllo |= DWC_CTLL_INT_EN;
+
+ prev->next = NULL;
+ prev->llp = 0;
+ prev->last = 1;
+ desc->last_lli = prev;
+
+ return desc;
+
+err_lli_get:
+ for (lli = desc->first_lli; lli; lli = lli->next)
+ dwc_lli_put(dwc, lli);
+ dwc_desc_put(dwc, desc);
+ return NULL;
+}
+
+static struct dma_async_tx_descriptor *
+dwc_prep_dma_memcpy(struct dma_chan *chan, size_t len, int int_en)
+{
+ struct dw_dma_chan *dwc = to_dw_dma_chan(chan);
+ struct dw_desc *desc;
+ u32 ctllo;
+
+ dev_vdbg(&chan->dev, "prep_dma_memcpy\n");
+
+ if (unlikely(!len))
+ return NULL;
+
+ /* FIXME: Try to use wider transfers when possible */
+ ctllo = DWC_DEFAULT_CTLLO
+ | DWC_CTLL_DST_WIDTH(0)
+ | DWC_CTLL_SRC_WIDTH(0)
+ | DWC_CTLL_DST_INC
+ | DWC_CTLL_SRC_INC
+ | DWC_CTLL_FC_M2M;
+
+ desc = dwc_prep_descriptor(dwc, ctllo, len, int_en);
+
+ return desc ? &desc->slave.txd : NULL;
+}
+
+static struct dma_slave_descriptor *dwc_prep_slave(struct dma_chan *chan,
+ size_t len, int int_en)
+{
+ struct dw_dma_chan *dwc = to_dw_dma_chan(chan);
+ struct dw_desc *desc;
+ u32 ctllo;
+
+ dev_vdbg(&chan->dev, "prep_dma_slave\n");
+
+ /*
+ * Most of the fields are filled out in the set_direction and
+ * set_width callbacks...
+ */
+ ctllo = DWC_DEFAULT_CTLLO;
+
+ desc = dwc_prep_descriptor(dwc, ctllo, len, int_en);
+
+ return desc ? &desc->slave : NULL;
+}
+
+static void dwc_set_slave(struct dma_chan *chan,
+ dma_addr_t rx_reg, unsigned int rx_hs_id,
+ dma_addr_t tx_reg, unsigned int tx_hs_id)
+{
+ struct dw_dma_chan *dwc = to_dw_dma_chan(chan);
+
+ BUG_ON(rx_hs_id > 15);
+ BUG_ON(tx_hs_id > 15);
+
+ channel_writel(dwc, CFG_HI, DWC_CFGH_SRC_PER(rx_hs_id)
+ | DWC_CFGH_DST_PER(tx_hs_id));
+
+ dwc->slave_rx_reg = rx_reg;
+ dwc->slave_tx_reg = tx_reg;
+}
+
+static void dwc_terminate_all(struct dma_chan *chan)
+{
+ struct dw_dma_chan *dwc = to_dw_dma_chan(chan);
+ struct dw_dma *dw = to_dw_dma(chan->device);
+
+ /*
+ * This is only called when something went wrong elsewhere, so
+ * we don't really care about the data. Just disable the
+ * channel. We still have to poll the channel enable bit due
+ * to AHB/HSB limitations.
+ */
+ channel_clear_bit(dw, CH_EN, dwc->mask);
+
+ while (dma_readl(dw, CH_EN) & dwc->mask)
+ cpu_relax();
+}
+
+static void dwc_dependency_added(struct dma_chan *chan)
+{
+ /* FIXME: What is this hook supposed to do? */
+}
+
+static enum dma_status
+dwc_is_tx_complete(struct dma_chan *chan,
+ dma_cookie_t cookie,
+ dma_cookie_t *done, dma_cookie_t *used)
+{
+ struct dw_dma_chan *dwc = to_dw_dma_chan(chan);
+ dma_cookie_t last_used;
+ dma_cookie_t last_complete;
+ int ret;
+
+ last_complete = dwc->completed;
+ last_used = chan->cookie;
+
+ ret = dma_async_is_complete(cookie, last_complete, last_used);
+ if (ret != DMA_SUCCESS) {
+ dwc_scan_descriptors(to_dw_dma(chan->device), dwc);
+
+ last_complete = dwc->completed;
+ last_used = chan->cookie;
+
+ ret = dma_async_is_complete(cookie, last_complete, last_used);
+ }
+
+ if (done)
+ *done = last_complete;
+ if (used)
+ *used = last_used;
+
+ return ret;
+}
+
+static void dwc_issue_pending(struct dma_chan *chan)
+{
+ struct dw_dma_chan *dwc = to_dw_dma_chan(chan);
+
+ spin_lock_bh(&dwc->lock);
+ if (dwc->last_queued)
+ dwc_scan_descriptors(to_dw_dma(chan->device), dwc);
+ spin_unlock_bh(&dwc->lock);
+}
+
+static int dwc_alloc_chan_resources(struct dma_chan *chan)
+{
+ struct dw_dma_chan *dwc = to_dw_dma_chan(chan);
+ struct dw_dma *dw = to_dw_dma(chan->device);
+ struct dw_desc *desc;
+ int i;
+
+ dev_vdbg(&chan->dev, "alloc_chan_resources\n");
+
+ /* ASSERT: channel is idle */
+ if (dma_readl(dw, CH_EN) & dwc->mask) {
+ dev_dbg(&chan->dev, "DMA channel not idle?\n");
+ return -EIO;
+ }
+
+ dwc->completed = chan->cookie = 1;
+
+ /* "no" handshaking, and no fancy games */
+ channel_writel(dwc, CFG_LO, 0);
+ channel_writel(dwc, CFG_HI, DWC_CFGH_FIFO_MODE);
+
+ /* NOTE: got access faults trying to clear SGR and DSR;
+ * also later when trying to read SSTATAR and DSTATAR...
+ */
+
+ spin_lock_bh(&dwc->lock);
+ i = dwc->descs_allocated;
+ while (dwc->descs_allocated < NR_DESCS_PER_CHANNEL) {
+ spin_unlock_bh(&dwc->lock);
+
+ desc = kzalloc(sizeof(struct dw_desc), GFP_KERNEL);
+ if (!desc) {
+ dev_info(&chan->dev,
+ "only allocated %d descriptors\n", i);
+ spin_lock_bh(&dwc->lock);
+ break;
+ }
+
+ dma_async_tx_descriptor_init(&desc->slave.txd, chan);
+ desc->slave.txd.ack = 1;
+ desc->slave.txd.tx_submit = dwc_tx_submit;
+ desc->slave.txd.tx_set_dest = dwc_tx_set_dest;
+ desc->slave.txd.tx_set_src = dwc_tx_set_src;
+ desc->slave.slave_set_direction = dwc_slave_set_direction;
+ desc->slave.slave_set_width = dwc_slave_set_width;
+
+ dev_vdbg(&chan->dev, " adding descriptor %p\n", desc);
+
+ spin_lock_bh(&dwc->lock);
+ i = ++dwc->descs_allocated;
+ list_add_tail(&desc->desc_node, &dwc->free_list);
+ }
+
+ /* Enable interrupts */
+ channel_set_bit(dw, MASK_XFER, dwc->mask);
+ channel_set_bit(dw, MASK_BLOCK, dwc->mask);
+ channel_set_bit(dw, MASK_ERROR, dwc->mask);
+
+ spin_unlock_bh(&dwc->lock);
+
+ dev_vdbg(&chan->dev,
+ "alloc_chan_resources allocated %d descriptors\n", i);
+
+ return i;
+}
+
+static void dwc_free_chan_resources(struct dma_chan *chan)
+{
+ struct dw_dma_chan *dwc = to_dw_dma_chan(chan);
+ struct dw_dma *dw = to_dw_dma(chan->device);
+ struct dw_desc *desc, *_desc;
+ LIST_HEAD(list);
+
+ dev_vdbg(&chan->dev, "free_chan_resources (descs allocated=%u)\n",
+ dwc->descs_allocated);
+
+ /* ASSERT: channel is idle */
+ BUG_ON(!list_empty(&dwc->active_list));
+ BUG_ON(!list_empty(&dwc->queue));
+ BUG_ON(dma_readl(to_dw_dma(chan->device), CH_EN) & dwc->mask);
+
+ spin_lock_bh(&dwc->lock);
+ list_splice_init(&dwc->free_list, &list);
+ dwc->descs_allocated = 0;
+
+ /* Disable interrupts */
+ channel_clear_bit(dw, MASK_XFER, dwc->mask);
+ channel_clear_bit(dw, MASK_BLOCK, dwc->mask);
+ channel_clear_bit(dw, MASK_ERROR, dwc->mask);
+
+ spin_unlock_bh(&dwc->lock);
+
+ list_for_each_entry_safe(desc, _desc, &list, desc_node) {
+ dev_vdbg(&chan->dev, " freeing descriptor %p\n", desc);
+ kfree(desc);
+ }
+
+ dev_vdbg(&chan->dev, "free_chan_resources done\n");
+}
+
+/*----------------------------------------------------------------------*/
+
+static void dw_dma_off(struct dw_dma *dw)
+{
+ dma_writel(dw, CFG, 0);
+
+ channel_clear_bit(dw, MASK_XFER, (1 << NDMA) - 1);
+ channel_clear_bit(dw, MASK_BLOCK, (1 << NDMA) - 1);
+ channel_clear_bit(dw, MASK_SRC_TRAN, (1 << NDMA) - 1);
+ channel_clear_bit(dw, MASK_DST_TRAN, (1 << NDMA) - 1);
+ channel_clear_bit(dw, MASK_ERROR, (1 << NDMA) - 1);
+
+ while (dma_readl(dw, CFG) & DW_CFG_DMA_EN)
+ cpu_relax();
+}
+
+static int __init dw_probe(struct platform_device *pdev)
+{
+ struct resource *io;
+ struct dw_dma *dw;
+#ifdef USE_DMA_POOL
+ struct dma_pool *lli_pool;
+#else
+ struct kmem_cache *lli_pool;
+#endif
+ int irq;
+ int err;
+ int i;
+
+ io = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!io)
+ return -EINVAL;
+
+ irq = platform_get_irq(pdev, 0);
+ if (irq < 0)
+ return irq;
+
+ /* FIXME platform_data holds NDMA. Use that to adjust the size
+ * of this allocation to match the silicon, and channel init.
+ */
+
+ dw = kzalloc(sizeof *dw, GFP_KERNEL);
+ if (!dw)
+ return -ENOMEM;
+
+ if (request_mem_region(io->start, DW_REGLEN,
+ pdev->dev.driver->name) == 0) {
+ err = -EBUSY;
+ goto err_kfree;
+ }
+
+ memset(dw, 0, sizeof *dw);
+
+ dw->regs = ioremap(io->start, DW_REGLEN);
+ if (!dw->regs) {
+ err = -ENOMEM;
+ goto err_release_r;
+ }
+
+ dw->clk = clk_get(&pdev->dev, "hclk");
+ if (IS_ERR(dw->clk)) {
+ err = PTR_ERR(dw->clk);
+ goto err_clk;
+ }
+ clk_enable(dw->clk);
+
+ /* force dma off, just in case */
+ dw_dma_off(dw);
+
+ err = request_irq(irq, dw_dma_interrupt, 0, "dw_dmac", dw);
+ if (err)
+ goto err_irq;
+
+#ifdef USE_DMA_POOL
+ lli_pool = dma_pool_create(pdev->dev.bus_id, &pdev->dev,
+ sizeof(struct dw_lli), 4, 0);
+#else
+ lli_pool = kmem_cache_create(pdev->dev.bus_id,
+ sizeof(struct dw_lli), 4, 0, NULL);
+#endif
+ if (!lli_pool) {
+ err = -ENOMEM;
+ goto err_dma_pool;
+ }
+
+ dw->lli_pool = lli_pool;
+ platform_set_drvdata(pdev, dw);
+
+ tasklet_init(&dw->tasklet, dw_dma_tasklet, (unsigned long)dw);
+
+ INIT_LIST_HEAD(&dw->dma.channels);
+ for (i = 0; i < NDMA; i++, dw->dma.chancnt++) {
+ struct dw_dma_chan *dwc = &dw->chan[i];
+
+ dwc->chan.device = &dw->dma;
+ dwc->chan.cookie = dwc->completed = 1;
+ dwc->chan.chan_id = i;
+ list_add_tail(&dwc->chan.device_node, &dw->dma.channels);
+
+ dwc->ch_regs = dw->regs + DW_DMAC_CHAN_BASE(i);
+ dwc->lli_pool = lli_pool;
+ spin_lock_init(&dwc->lock);
+ dwc->mask = 1 << i;
+
+ /* FIXME dmaengine API bug: the dma_device isn't coupled
+ * to the underlying hardware; so neither is the dma_chan.
+ *
+ * Workaround: dwc->dev instead of dwc->chan.cdev.dev
+ * (or eventually dwc->chan.dev.parent).
+ */
+ dwc->dev = &pdev->dev;
+
+ INIT_LIST_HEAD(&dwc->active_list);
+ INIT_LIST_HEAD(&dwc->queue);
+ INIT_LIST_HEAD(&dwc->free_list);
+
+ channel_clear_bit(dw, CH_EN, dwc->mask);
+ }
+
+ /* Clear/disable all interrupts on all channels. */
+ dma_writel(dw, CLEAR_XFER, (1 << NDMA) - 1);
+ dma_writel(dw, CLEAR_BLOCK, (1 << NDMA) - 1);
+ dma_writel(dw, CLEAR_SRC_TRAN, (1 << NDMA) - 1);
+ dma_writel(dw, CLEAR_DST_TRAN, (1 << NDMA) - 1);
+ dma_writel(dw, CLEAR_ERROR, (1 << NDMA) - 1);
+
+ channel_clear_bit(dw, MASK_XFER, (1 << NDMA) - 1);
+ channel_clear_bit(dw, MASK_BLOCK, (1 << NDMA) - 1);
+ channel_clear_bit(dw, MASK_SRC_TRAN, (1 << NDMA) - 1);
+ channel_clear_bit(dw, MASK_DST_TRAN, (1 << NDMA) - 1);
+ channel_clear_bit(dw, MASK_ERROR, (1 << NDMA) - 1);
+
+ dma_cap_set(DMA_MEMCPY, dw->dma.cap_mask);
+ dma_cap_set(DMA_SLAVE, dw->dma.cap_mask);
+ dw->dma.dev = &pdev->dev;
+ dw->dma.device_alloc_chan_resources = dwc_alloc_chan_resources;
+ dw->dma.device_free_chan_resources = dwc_free_chan_resources;
+
+ dw->dma.device_prep_dma_memcpy = dwc_prep_dma_memcpy;
+
+ dw->dma.device_set_slave = dwc_set_slave;
+ dw->dma.device_prep_slave = dwc_prep_slave;
+ dw->dma.device_terminate_all = dwc_terminate_all;
+
+ dw->dma.device_dependency_added = dwc_dependency_added;
+ dw->dma.device_is_tx_complete = dwc_is_tx_complete;
+ dw->dma.device_issue_pending = dwc_issue_pending;
+
+ dma_writel(dw, CFG, DW_CFG_DMA_EN);
+
+ printk(KERN_INFO "%s: DesignWare DMA Controller, %d channels\n",
+ pdev->dev.bus_id, dw->dma.chancnt);
+
+ dma_async_device_register(&dw->dma);
+
+ return 0;
+
+err_dma_pool:
+ free_irq(irq, dw);
+err_irq:
+ clk_disable(dw->clk);
+ clk_put(dw->clk);
+err_clk:
+ iounmap(dw->regs);
+ dw->regs = NULL;
+err_release_r:
+ release_resource(io);
+err_kfree:
+ kfree(dw);
+ return err;
+}
+
+static int __exit dw_remove(struct platform_device *pdev)
+{
+ struct dw_dma *dw = platform_get_drvdata(pdev);
+ struct dw_dma_chan *dwc, *_dwc;
+ struct resource *io;
+
+ dev_dbg(&pdev->dev, "dw_remove\n");
+
+ dw_dma_off(dw);
+ dma_async_device_unregister(&dw->dma);
+
+ free_irq(platform_get_irq(pdev, 0), dw);
+ tasklet_kill(&dw->tasklet);
+
+ list_for_each_entry_safe(dwc, _dwc, &dw->dma.channels,
+ chan.device_node) {
+ list_del(&dwc->chan.device_node);
+ channel_clear_bit(dw, CH_EN, dwc->mask);
+ }
+
+#ifdef USE_DMA_POOL
+ dma_pool_destroy(dw->lli_pool);
+#else
+ kmem_cache_destroy(dw->lli_pool);
+#endif
+
+ clk_disable(dw->clk);
+ clk_put(dw->clk);
+
+ iounmap(dw->regs);
+ dw->regs = NULL;
+
+ io = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ release_mem_region(io->start, DW_REGLEN);
+
+ kfree(dw);
+
+ dev_dbg(&pdev->dev, "dw_remove done\n");
+
+ return 0;
+}
+
+static void dw_shutdown(struct platform_device *pdev)
+{
+ struct dw_dma *dw = platform_get_drvdata(pdev);
+
+ dw_dma_off(platform_get_drvdata(pdev));
+ clk_disable(dw->clk);
+}
+
+static int dw_suspend_late(struct platform_device *pdev, pm_message_t mesg)
+{
+ struct dw_dma *dw = platform_get_drvdata(pdev);
+
+ dw_dma_off(platform_get_drvdata(pdev));
+ clk_disable(dw->clk);
+ return 0;
+}
+
+static int dw_resume_early(struct platform_device *pdev)
+{
+ struct dw_dma *dw = platform_get_drvdata(pdev);
+
+ clk_enable(dw->clk);
+ dma_writel(dw, CFG, DW_CFG_DMA_EN);
+ return 0;
+
+}
+
+static struct platform_driver dw_driver = {
+ .remove = __exit_p(dw_remove),
+ .shutdown = dw_shutdown,
+ .suspend_late = dw_suspend_late,
+ .resume_early = dw_resume_early,
+ .driver = {
+ .name = "dw_dmac",
+ },
+};
+
+static int __init dw_init(void)
+{
+ BUILD_BUG_ON(NDMA > 8);
+ return platform_driver_probe(&dw_driver, dw_probe);
+}
+device_initcall(dw_init);
+
+static void __exit dw_exit(void)
+{
+ platform_driver_unregister(&dw_driver);
+}
+module_exit(dw_exit);
+
+MODULE_LICENSE("GPL");
diff --git a/drivers/dma/dw_dmac.h b/drivers/dma/dw_dmac.h
new file mode 100644
index 0000000..cd38d0b
--- /dev/null
+++ b/drivers/dma/dw_dmac.h
@@ -0,0 +1,257 @@
+/*
+ * Driver for the Synopsys DesignWare AHB DMA Controller
+ *
+ * Copyright (C) 2005-2007 Atmel Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+/* REVISIT Synopsys provides a C header; use symbols from there instead? */
+
+/* per-channel registers */
+#define DW_DMAC_CHAN_SAR 0x000
+#define DW_DMAC_CHAN_DAR 0x008
+#define DW_DMAC_CHAN_LLP 0x010
+#define DW_DMAC_CHAN_CTL_LO 0x018
+# define DWC_CTLL_INT_EN (1 << 0) /* irqs enabled? */
+# define DWC_CTLL_DST_WIDTH(n) ((n)<<1) /* bytes per element */
+# define DWC_CTLL_SRC_WIDTH(n) ((n)<<4)
+# define DWC_CTLL_DST_INC (0<<7) /* DAR update/not */
+# define DWC_CTLL_DST_DEC (1<<7)
+# define DWC_CTLL_DST_FIX (2<<7)
+# define DWC_CTLL_SRC_INC (0<<7) /* SAR update/not */
+# define DWC_CTLL_SRC_DEC (1<<9)
+# define DWC_CTLL_SRC_FIX (2<<9)
+# define DWC_CTLL_DST_MSIZE(n) ((n)<<11) /* burst, #elements */
+# define DWC_CTLL_SRC_MSIZE(n) ((n)<<14)
+# define DWC_CTLL_S_GATH_EN (1 << 17) /* src gather, !FIX */
+# define DWC_CTLL_D_SCAT_EN (1 << 18) /* dst scatter, !FIX */
+# define DWC_CTLL_FC_M2M (0 << 20) /* mem-to-mem */
+# define DWC_CTLL_FC_M2P (1 << 20) /* mem-to-periph */
+# define DWC_CTLL_FC_P2M (2 << 20) /* periph-to-mem */
+# define DWC_CTLL_FC_P2P (3 << 20) /* periph-to-periph */
+ /* plus 4 transfer types for peripheral-as-flow-controller */
+# define DWC_CTLL_DMS(n) ((n)<<23)
+# define DWC_CTLL_SMS(n) ((n)<<25)
+# define DWC_CTLL_LLP_D_EN (1 << 27) /* dest block chain */
+# define DWC_CTLL_LLP_S_EN (1 << 28) /* src block chain */
+#define DW_DMAC_CHAN_CTL_HI 0x01c
+# define DWC_CTLH_DONE 0x00001000
+# define DWC_CTLH_BLOCK_TS_MASK 0x00000fff
+#define DW_DMAC_CHAN_SSTAT 0x020
+#define DW_DMAC_CHAN_DSTAT 0x028
+#define DW_DMAC_CHAN_SSTATAR 0x030
+#define DW_DMAC_CHAN_DSTATAR 0x038
+#define DW_DMAC_CHAN_CFG_LO 0x040
+# define DWC_CFGL_PRIO(x) ((x) << 5) /* priority */
+# define DWC_CFGL_CH_SUSP (1 << 8) /* pause xfer */
+# define DWC_CFGL_FIFO_EMPTY (1 << 9) /* pause xfer */
+# define DWC_CFGL_HS_DST (1 << 10) /* handshake w/dst */
+# define DWC_CFGL_HS_SRC (1 << 11) /* handshake w/src */
+# define DWC_CFGL_LOCK_CH_XFER (0 << 12) /* scope of LOCK_CH */
+# define DWC_CFGL_LOCK_CH_BLOCK (1 << 12)
+# define DWC_CFGL_LOCK_CH_XACT (2 << 12)
+# define DWC_CFGL_LOCK_BUS_XFER (0 << 14) /* scope of LOCK_BUS */
+# define DWC_CFGL_LOCK_BUS_BLOCK (1 << 14)
+# define DWC_CFGL_LOCK_BUS_XACT (2 << 14)
+# define DWC_CFGL_LOCK_CH (1 << 15) /* channel lockout */
+# define DWC_CFGL_LOCK_BUS (1 << 16) /* busmaster lockout */
+# define DWC_CFGL_HS_DST_POL (1 << 18)
+# define DWC_CFGL_HS_SRC_POL (1 << 19)
+# define DWC_CFGL_MAX_BURST(x) ((x) << 20)
+# define DWC_CFGL_RELOAD_SAR (1 << 30)
+# define DWC_CFGL_RELOAD_DAR (1 << 31)
+#define DW_DMAC_CHAN_CFG_HI 0x044
+# define DWC_CFGH_FCMODE (1 << 0)
+# define DWC_CFGH_FIFO_MODE (1 << 1)
+# define DWC_CFGH_PROTCTL(x) ((x) << 2)
+# define DWC_CFGH_DS_UPD_EN (1 << 5)
+# define DWC_CFGH_SS_UPD_EN (1 << 6)
+# define DWC_CFGH_SRC_PER(x) ((x) << 7)
+# define DWC_CFGH_DST_PER(x) ((x) << 11)
+#define DW_DMAC_CHAN_SGR 0x048
+# define DWC_SGR_SGI(x) ((x) << 0)
+# define DWC_SGR_SGC(x) ((x) << 20)
+#define DW_DMAC_CHAN_DSR 0x050
+# define DWC_DSR_DSI(x) ((x) << 0)
+# define DWC_DSR_DSC(x) ((x) << 20)
+
+#define DW_DMAC_CHAN_BASE(n) ((n)*0x58)
+
+/* irq handling */
+#define DW_DMAC_RAW_XFER 0x2c0 /* r */
+#define DW_DMAC_RAW_BLOCK 0x2c8
+#define DW_DMAC_RAW_SRC_TRAN 0x2d0
+#define DW_DMAC_RAW_DST_TRAN 0x2d8
+#define DW_DMAC_RAW_ERROR 0x2e0
+
+#define DW_DMAC_STATUS_XFER 0x2e8 /* r (raw & mask) */
+#define DW_DMAC_STATUS_BLOCK 0x2f0
+#define DW_DMAC_STATUS_SRC_TRAN 0x2f8
+#define DW_DMAC_STATUS_DST_TRAN 0x300
+#define DW_DMAC_STATUS_ERROR 0x308
+
+#define DW_DMAC_MASK_XFER 0x310 /* rw (set = irq enabled) */
+#define DW_DMAC_MASK_BLOCK 0x318
+#define DW_DMAC_MASK_SRC_TRAN 0x320
+#define DW_DMAC_MASK_DST_TRAN 0x328
+#define DW_DMAC_MASK_ERROR 0x330
+
+#define DW_DMAC_CLEAR_XFER 0x338 /* w (ack, affects "raw") */
+#define DW_DMAC_CLEAR_BLOCK 0x340
+#define DW_DMAC_CLEAR_SRC_TRAN 0x348
+#define DW_DMAC_CLEAR_DST_TRAN 0x350
+#define DW_DMAC_CLEAR_ERROR 0x358
+
+#define DW_DMAC_STATUS_INT 0x360 /* r */
+
+/* software handshaking */
+#define DW_DMAC_REQ_SRC 0x368 /* rw */
+#define DW_DMAC_REQ_DST 0x370
+#define DW_DMAC_SGL_REQ_SRC 0x378
+#define DW_DMAC_SGL_REQ_DST 0x380
+#define DW_DMAC_LAST_SRC 0x388
+#define DW_DMAC_LAST_DST 0x390
+
+/* miscellaneous */
+#define DW_DMAC_CFG 0x398 /* rw */
+# define DW_CFG_DMA_EN (1 << 0)
+#define DW_DMAC_CH_EN 0x3a0
+
+#define DW_DMAC_ID 0x3a8 /* r */
+#define DW_DMAC_TEST 0x3b0 /* rw */
+
+/* optional encoded params, 0x3c8..0x3 */
+
+#define DW_REGLEN 0x400
+
+
+/* How many channels ... potentially, up to 8 */
+#ifdef CONFIG_CPU_AT32AP7000
+#define NDMA 3
+#endif
+
+#ifndef NDMA
+/* REVISIT want a better (static) solution than this */
+#warning system unrecognized, assuming max NDMA=8
+#define NDMA 8
+#endif
+
+struct dw_dma_chan {
+ struct dma_chan chan;
+ void __iomem *ch_regs;
+#ifdef USE_DMA_POOL
+ struct dma_pool *lli_pool;
+#else
+ struct kmem_cache *lli_pool;
+#endif
+ struct device *dev;
+
+ u8 mask;
+
+ spinlock_t lock;
+
+ /* these other elements are all protected by lock */
+ dma_cookie_t completed;
+ struct list_head active_list;
+ struct list_head queue;
+ struct list_head free_list;
+
+ struct dw_lli *last_lli;
+ struct dw_lli *first_queued;
+ struct dw_lli *last_queued;
+
+ dma_addr_t slave_rx_reg;
+ dma_addr_t slave_tx_reg;
+
+ unsigned int descs_allocated;
+};
+
+/* REVISIT these register access macros cause inefficient code: the st.w
+ * and ld.w displacements are all zero, never DW_DMAC_ constants embedded
+ * in the instructions. GCC 4.0.2-atmel.0.99.2 issue? Struct access is
+ * as efficient as one would expect...
+ */
+
+#define channel_readl(dwc, name) \
+ __raw_readl((dwc)->ch_regs + DW_DMAC_CHAN_##name)
+#define channel_writel(dwc, name, val) \
+ __raw_writel((val), (dwc)->ch_regs + DW_DMAC_CHAN_##name)
+
+static inline struct dw_dma_chan *to_dw_dma_chan(struct dma_chan *chan)
+{
+ return container_of(chan, struct dw_dma_chan, chan);
+}
+
+
+struct dw_dma {
+ struct dma_device dma;
+ void __iomem *regs;
+#ifdef USE_DMA_POOL
+ struct dma_pool *lli_pool;
+#else
+ struct kmem_cache *lli_pool;
+#endif
+ struct tasklet_struct tasklet;
+ struct clk *clk;
+ struct dw_dma_chan chan[NDMA];
+};
+
+#define dma_readl(dw, name) \
+ __raw_readl((dw)->regs + DW_DMAC_##name)
+#define dma_writel(dw, name, val) \
+ __raw_writel((val), (dw)->regs + DW_DMAC_##name)
+
+#define channel_set_bit(dw, reg, mask) \
+ dma_writel(dw, reg, ((mask) << 8) | (mask))
+#define channel_clear_bit(dw, reg, mask) \
+ dma_writel(dw, reg, ((mask) << 8) | 0)
+
+static inline struct dw_dma *to_dw_dma(struct dma_device *ddev)
+{
+ return container_of(ddev, struct dw_dma, dma);
+}
+
+
+/* LLI == Linked List Item; a.k.a. DMA block descriptor */
+struct dw_lli {
+ /* FIRST values the hardware uses */
+ dma_addr_t sar;
+ dma_addr_t dar;
+ dma_addr_t llp; /* chain to next lli */
+ u32 ctllo;
+ /* values that may get written back: */
+ u32 ctlhi;
+ /* sstat and dstat can snapshot peripheral register state.
+ * silicon config may discard either or both...
+ */
+ u32 sstat;
+ u32 dstat;
+
+ /* THEN values for driver housekeeping */
+ struct dw_lli *next;
+ dma_addr_t phys;
+ int last;
+};
+
+struct dw_desc {
+ struct dw_lli *first_lli;
+ struct dw_lli *last_lli;
+
+ struct dma_slave_descriptor slave;
+ struct list_head desc_node;
+};
+
+static inline struct dw_desc *
+txd_to_dw_desc(struct dma_async_tx_descriptor *txd)
+{
+ return container_of(txd, struct dw_desc, slave.txd);
+}
+
+static inline struct dw_desc *
+sd_to_dw_desc(struct dma_slave_descriptor *sd)
+{
+ return container_of(sd, struct dw_desc, slave);
+}
diff --git a/include/asm-avr32/arch-at32ap/at32ap7000.h b/include/asm-avr32/arch-at32ap/at32ap7000.h
index 3914d7b..a6e53cd 100644
--- a/include/asm-avr32/arch-at32ap/at32ap7000.h
+++ b/include/asm-avr32/arch-at32ap/at32ap7000.h
@@ -32,4 +32,20 @@
#define GPIO_PIN_PD(N) (GPIO_PIOD_BASE + (N))
#define GPIO_PIN_PE(N) (GPIO_PIOE_BASE + (N))
+
+/*
+ * DMAC peripheral hardware handshaking interfaces, used with dw_dmac
+ */
+#define DMAC_MCI_RX 0
+#define DMAC_MCI_TX 1
+#define DMAC_DAC_TX 2
+#define DMAC_AC97_A_RX 3
+#define DMAC_AC97_A_TX 4
+#define DMAC_AC97_B_RX 5
+#define DMAC_AC97_B_TX 6
+#define DMAC_DMAREQ_0 7
+#define DMAC_DMAREQ_1 8
+#define DMAC_DMAREQ_2 9
+#define DMAC_DMAREQ_3 10
+
#endif /* __ASM_ARCH_AT32AP7000_H__ */
--
1.5.3.4
^ permalink raw reply related [flat|nested] 11+ messages in thread
* [RFC 4/4] Atmel MCI: Driver for Atmel on-chip MMC controllers
2007-11-23 12:20 ` [RFC 3/4] dmaengine: Driver for the Synopsys DesignWare DMA controller Haavard Skinnemoen
@ 2007-11-23 12:20 ` Haavard Skinnemoen
2007-11-24 17:00 ` Pierre Ossman
0 siblings, 1 reply; 11+ messages in thread
From: Haavard Skinnemoen @ 2007-11-23 12:20 UTC (permalink / raw)
To: linux-kernel
Cc: Shannon Nelson, Dan Williams, David Brownell, kernel,
linux-arm-kernel, Haavard Skinnemoen
This is a driver for the MMC controller on the AP7000 chips from
Atmel. It should in theory work on AT91 systems too with some
tweaking, but since the DMA interface is quite different, it's not
entirely clear if it's worth it.
This driver has been around for a while in BSPs and kernel sources
provided by Atmel, but this particular version uses the generic DMA
Engine framework (with the slave extensions) instead of an
avr32-only DMA controller framework.
Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
---
arch/avr32/boards/atngw100/setup.c | 6 +
arch/avr32/boards/atstk1000/atstk1002.c | 3 +
arch/avr32/mach-at32ap/at32ap7000.c | 31 +-
drivers/mmc/host/Kconfig | 10 +
drivers/mmc/host/Makefile | 1 +
drivers/mmc/host/atmel-mci.c | 1170 +++++++++++++++++++++++++++++++
drivers/mmc/host/atmel-mci.h | 192 +++++
include/asm-avr32/arch-at32ap/board.h | 10 +-
8 files changed, 1417 insertions(+), 6 deletions(-)
create mode 100644 drivers/mmc/host/atmel-mci.c
create mode 100644 drivers/mmc/host/atmel-mci.h
diff --git a/arch/avr32/boards/atngw100/setup.c b/arch/avr32/boards/atngw100/setup.c
index 52987c8..8c69ebf 100644
--- a/arch/avr32/boards/atngw100/setup.c
+++ b/arch/avr32/boards/atngw100/setup.c
@@ -42,6 +42,11 @@ static struct spi_board_info spi0_board_info[] __initdata = {
},
};
+static struct mci_platform_data __initdata mci0_data = {
+ .detect_pin = GPIO_PIN_PC(25),
+ .wp_pin = GPIO_PIN_PE(0),
+};
+
/*
* The next two functions should go away as the boot loader is
* supposed to initialize the macb address registers with a valid
@@ -157,6 +162,7 @@ static int __init atngw100_init(void)
set_hw_addr(at32_add_device_eth(1, ð_data[1]));
at32_add_device_spi(0, spi0_board_info, ARRAY_SIZE(spi0_board_info));
+ at32_add_device_mci(0, &mci0_data);
at32_add_device_usba(0, NULL);
for (i = 0; i < ARRAY_SIZE(ngw_leds); i++) {
diff --git a/arch/avr32/boards/atstk1000/atstk1002.c b/arch/avr32/boards/atstk1000/atstk1002.c
index 5be0d13..1b2f6eb 100644
--- a/arch/avr32/boards/atstk1000/atstk1002.c
+++ b/arch/avr32/boards/atstk1000/atstk1002.c
@@ -287,6 +287,9 @@ static int __init atstk1002_init(void)
#ifdef CONFIG_BOARD_ATSTK1002_SPI1
at32_add_device_spi(1, spi1_board_info, ARRAY_SIZE(spi1_board_info));
#endif
+#ifndef CONFIG_BOARD_ATSTK1002_SW2_CUSTOM
+ at32_add_device_mci(0, NULL);
+#endif
#ifdef CONFIG_BOARD_ATSTK1002_SW5_CUSTOM
set_hw_addr(at32_add_device_eth(1, ð_data[1]));
#else
diff --git a/arch/avr32/mach-at32ap/at32ap7000.c b/arch/avr32/mach-at32ap/at32ap7000.c
index 1759f0d..03cb6c2 100644
--- a/arch/avr32/mach-at32ap/at32ap7000.c
+++ b/arch/avr32/mach-at32ap/at32ap7000.c
@@ -1032,20 +1032,34 @@ static struct clk atmel_mci0_pclk = {
.index = 9,
};
-struct platform_device *__init at32_add_device_mci(unsigned int id)
+struct platform_device *__init
+at32_add_device_mci(unsigned int id, struct mci_platform_data *data)
{
- struct platform_device *pdev;
+ struct mci_platform_data _data;
+ struct platform_device *pdev;
if (id != 0)
return NULL;
pdev = platform_device_alloc("atmel_mci", id);
if (!pdev)
- return NULL;
+ goto fail;
if (platform_device_add_resources(pdev, atmel_mci0_resource,
ARRAY_SIZE(atmel_mci0_resource)))
- goto err_add_resources;
+ goto fail;
+
+ if (!data) {
+ data = &_data;
+ memset(data, 0, sizeof(struct mci_platform_data));
+ }
+
+ data->rx_periph_id = 0;
+ data->tx_periph_id = 1;
+
+ if (platform_device_add_data(pdev, data,
+ sizeof(struct mci_platform_data)))
+ goto fail;
select_peripheral(PA(10), PERIPH_A, 0); /* CLK */
select_peripheral(PA(11), PERIPH_A, 0); /* CMD */
@@ -1054,12 +1068,19 @@ struct platform_device *__init at32_add_device_mci(unsigned int id)
select_peripheral(PA(14), PERIPH_A, 0); /* DATA2 */
select_peripheral(PA(15), PERIPH_A, 0); /* DATA3 */
+ if (data) {
+ if (data->detect_pin != GPIO_PIN_NONE)
+ at32_select_gpio(data->detect_pin, 0);
+ if (data->wp_pin != GPIO_PIN_NONE)
+ at32_select_gpio(data->wp_pin, 0);
+ }
+
atmel_mci0_pclk.dev = &pdev->dev;
platform_device_add(pdev);
return pdev;
-err_add_resources:
+fail:
platform_device_put(pdev);
return NULL;
}
diff --git a/drivers/mmc/host/Kconfig b/drivers/mmc/host/Kconfig
index 5fef678..687cf8b 100644
--- a/drivers/mmc/host/Kconfig
+++ b/drivers/mmc/host/Kconfig
@@ -91,6 +91,16 @@ config MMC_AT91
If unsure, say N.
+config MMC_ATMELMCI
+ tristate "Atmel Multimedia Card Interface support"
+ depends on AVR32 && DMA_ENGINE
+ help
+ This selects the Atmel Multimedia Card Interface. If you have
+ a AT91 (ARM) or AT32 (AVR32) platform with a Multimedia Card
+ slot, say Y or M here.
+
+ If unsure, say N.
+
config MMC_IMX
tristate "Motorola i.MX Multimedia Card Interface support"
depends on ARCH_IMX
diff --git a/drivers/mmc/host/Makefile b/drivers/mmc/host/Makefile
index 3877c87..e80ea72 100644
--- a/drivers/mmc/host/Makefile
+++ b/drivers/mmc/host/Makefile
@@ -15,6 +15,7 @@ obj-$(CONFIG_MMC_WBSD) += wbsd.o
obj-$(CONFIG_MMC_AU1X) += au1xmmc.o
obj-$(CONFIG_MMC_OMAP) += omap.o
obj-$(CONFIG_MMC_AT91) += at91_mci.o
+obj-$(CONFIG_MMC_ATMELMCI) += atmel-mci.o
obj-$(CONFIG_MMC_TIFM_SD) += tifm_sd.o
obj-$(CONFIG_MMC_SPI) += mmc_spi.o
diff --git a/drivers/mmc/host/atmel-mci.c b/drivers/mmc/host/atmel-mci.c
new file mode 100644
index 0000000..aae3273
--- /dev/null
+++ b/drivers/mmc/host/atmel-mci.c
@@ -0,0 +1,1170 @@
+/*
+ * Atmel MultiMedia Card Interface driver
+ *
+ * Copyright (C) 2004-2007 Atmel Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#include <linux/blkdev.h>
+#include <linux/clk.h>
+#include <linux/device.h>
+#include <linux/dma-mapping.h>
+#include <linux/dmaengine.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/ioport.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+
+#include <linux/mmc/host.h>
+
+#include <asm/io.h>
+#include <asm/arch/board.h>
+#include <asm/arch/gpio.h>
+
+#include "atmel-mci.h"
+
+#define DRIVER_NAME "atmel_mci"
+
+#define MCI_DATA_ERROR_FLAGS (MCI_BIT(DCRCE) | MCI_BIT(DTOE) | \
+ MCI_BIT(OVRE) | MCI_BIT(UNRE))
+
+enum {
+ EVENT_CMD_COMPLETE = 0,
+ EVENT_DATA_COMPLETE,
+ EVENT_DATA_ERROR,
+ EVENT_STOP_SENT,
+ EVENT_STOP_COMPLETE,
+ EVENT_DMA_COMPLETE,
+ EVENT_DMA_ERROR,
+ EVENT_CARD_DETECT,
+};
+
+struct atmel_mci_dma {
+ struct dma_client client;
+ struct dma_chan *chan;
+ struct list_head data_descs;
+};
+
+struct atmel_mci {
+ struct mmc_host *mmc;
+ void __iomem *regs;
+ struct atmel_mci_dma dma;
+
+ struct mmc_request *mrq;
+ struct mmc_command *cmd;
+ struct mmc_data *data;
+
+ u32 cmd_status;
+ u32 data_status;
+ u32 stop_status;
+ u32 stop_cmdr;
+
+ struct tasklet_struct tasklet;
+ unsigned long pending_events;
+ unsigned long completed_events;
+
+ int present;
+ int detect_pin;
+ int wp_pin;
+
+ unsigned long bus_hz;
+ unsigned long mapbase;
+ struct clk *mck;
+ struct platform_device *pdev;
+
+#ifdef CONFIG_DEBUG_FS
+ struct dentry *debugfs_root;
+ struct dentry *debugfs_regs;
+ struct dentry *debugfs_req;
+ struct dentry *debugfs_pending_events;
+ struct dentry *debugfs_completed_events;
+#endif
+};
+
+static inline struct atmel_mci *
+dma_client_to_atmel_mci(struct dma_client *client)
+{
+ return container_of(client, struct atmel_mci, dma.client);
+}
+
+/* Those printks take an awful lot of time... */
+#ifndef DEBUG
+static unsigned int fmax = 15000000U;
+#else
+static unsigned int fmax = 1000000U;
+#endif
+module_param(fmax, uint, 0444);
+MODULE_PARM_DESC(fmax, "Max frequency in Hz of the MMC bus clock");
+
+#define atmci_is_completed(host, event) \
+ test_bit(event, &host->completed_events)
+#define atmci_test_and_clear_pending(host, event) \
+ test_and_clear_bit(event, &host->pending_events)
+#define atmci_test_and_set_completed(host, event) \
+ test_and_set_bit(event, &host->completed_events)
+#define atmci_set_completed(host, event) \
+ set_bit(event, &host->completed_events)
+#define atmci_set_pending(host, event) \
+ set_bit(event, &host->pending_events)
+#define atmci_clear_pending(host, event) \
+ clear_bit(event, &host->pending_events)
+
+
+#ifdef CONFIG_DEBUG_FS
+#include <linux/debugfs.h>
+
+#define DBG_REQ_BUF_SIZE (4096 - sizeof(unsigned int))
+
+struct req_dbg_data {
+ unsigned int nbytes;
+ char str[DBG_REQ_BUF_SIZE];
+};
+
+static int req_dbg_open(struct inode *inode, struct file *file)
+{
+ struct atmel_mci *host;
+ struct mmc_request *mrq;
+ struct mmc_command *cmd;
+ struct mmc_command *stop;
+ struct mmc_data *data;
+ struct req_dbg_data *priv;
+ char *str;
+ unsigned long n = 0;
+
+ priv = kzalloc(DBG_REQ_BUF_SIZE, GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+ str = priv->str;
+
+ mutex_lock(&inode->i_mutex);
+ host = inode->i_private;
+
+ spin_lock_irq(&host->mmc->lock);
+ mrq = host->mrq;
+ if (mrq) {
+ cmd = mrq->cmd;
+ data = mrq->data;
+ stop = mrq->stop;
+ n = snprintf(str, DBG_REQ_BUF_SIZE,
+ "CMD%u(0x%x) %x %x %x %x %x (err %u)\n",
+ cmd->opcode, cmd->arg, cmd->flags,
+ cmd->resp[0], cmd->resp[1], cmd->resp[2],
+ cmd->resp[3], cmd->error);
+ if (n < DBG_REQ_BUF_SIZE && data)
+ n += snprintf(str + n, DBG_REQ_BUF_SIZE - n,
+ "DATA %u * %u (%u) %x (err %u)\n",
+ data->blocks, data->blksz,
+ data->bytes_xfered, data->flags,
+ data->error);
+ if (n < DBG_REQ_BUF_SIZE && stop)
+ n += snprintf(str + n, DBG_REQ_BUF_SIZE - n,
+ "CMD%u(0x%x) %x %x %x %x %x (err %u)\n",
+ stop->opcode, stop->arg, stop->flags,
+ stop->resp[0], stop->resp[1],
+ stop->resp[2], stop->resp[3],
+ stop->error);
+ }
+ spin_unlock_irq(&host->mmc->lock);
+ mutex_unlock(&inode->i_mutex);
+
+ priv->nbytes = min(n, DBG_REQ_BUF_SIZE);
+ file->private_data = priv;
+
+ return 0;
+}
+
+static ssize_t req_dbg_read(struct file *file, char __user *buf,
+ size_t nbytes, loff_t *ppos)
+{
+ struct req_dbg_data *priv = file->private_data;
+
+ return simple_read_from_buffer(buf, nbytes, ppos,
+ priv->str, priv->nbytes);
+}
+
+static int req_dbg_release(struct inode *inode, struct file *file)
+{
+ kfree(file->private_data);
+ return 0;
+}
+
+static const struct file_operations req_dbg_fops = {
+ .owner = THIS_MODULE,
+ .open = req_dbg_open,
+ .llseek = no_llseek,
+ .read = req_dbg_read,
+ .release = req_dbg_release,
+};
+
+static int regs_dbg_open(struct inode *inode, struct file *file)
+{
+ struct atmel_mci *host;
+ unsigned int i;
+ u32 *data;
+ int ret;
+
+ mutex_lock(&inode->i_mutex);
+ host = inode->i_private;
+ data = kmalloc(inode->i_size, GFP_KERNEL);
+ if (!data) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ spin_lock_irq(&host->mmc->lock);
+ for (i = 0; i < inode->i_size / 4; i++)
+ data[i] = __raw_readl(host->regs + i * 4);
+ spin_unlock_irq(&host->mmc->lock);
+
+ file->private_data = data;
+ ret = 0;
+
+out:
+ mutex_unlock(&inode->i_mutex);
+
+ return ret;
+}
+
+static ssize_t regs_dbg_read(struct file *file, char __user *buf,
+ size_t nbytes, loff_t *ppos)
+{
+ struct inode *inode = file->f_dentry->d_inode;
+ int ret;
+
+ mutex_lock(&inode->i_mutex);
+ ret = simple_read_from_buffer(buf, nbytes, ppos,
+ file->private_data,
+ file->f_dentry->d_inode->i_size);
+ mutex_unlock(&inode->i_mutex);
+
+ return ret;
+}
+
+static int regs_dbg_release(struct inode *inode, struct file *file)
+{
+ kfree(file->private_data);
+ return 0;
+}
+
+static const struct file_operations regs_dbg_fops = {
+ .owner = THIS_MODULE,
+ .open = regs_dbg_open,
+ .llseek = generic_file_llseek,
+ .read = regs_dbg_read,
+ .release = regs_dbg_release,
+};
+
+static void atmci_init_debugfs(struct atmel_mci *host)
+{
+ struct mmc_host *mmc;
+ struct dentry *root;
+ struct dentry *regs;
+ struct resource *res;
+
+ mmc = host->mmc;
+ root = debugfs_create_dir(mmc_hostname(mmc), NULL);
+ if (IS_ERR(root) || !root)
+ goto err_root;
+ host->debugfs_root = root;
+
+ regs = debugfs_create_file("regs", 0400, root, host, ®s_dbg_fops);
+ if (!regs)
+ goto err_regs;
+
+ res = platform_get_resource(host->pdev, IORESOURCE_MEM, 0);
+ regs->d_inode->i_size = res->end - res->start + 1;
+ host->debugfs_regs = regs;
+
+ host->debugfs_req = debugfs_create_file("req", 0400, root,
+ host, &req_dbg_fops);
+ if (!host->debugfs_req)
+ goto err_req;
+
+ host->debugfs_pending_events
+ = debugfs_create_u32("pending_events", 0400, root,
+ (u32 *)&host->pending_events);
+ if (!host->debugfs_pending_events)
+ goto err_pending_events;
+
+ host->debugfs_completed_events
+ = debugfs_create_u32("completed_events", 0400, root,
+ (u32 *)&host->completed_events);
+ if (!host->debugfs_completed_events)
+ goto err_completed_events;
+
+ return;
+
+err_completed_events:
+ debugfs_remove(host->debugfs_pending_events);
+err_pending_events:
+ debugfs_remove(host->debugfs_req);
+err_req:
+ debugfs_remove(host->debugfs_regs);
+err_regs:
+ debugfs_remove(host->debugfs_root);
+err_root:
+ host->debugfs_root = NULL;
+ dev_err(&host->pdev->dev,
+ "failed to initialize debugfs for %s\n",
+ mmc_hostname(mmc));
+}
+
+static void atmci_cleanup_debugfs(struct atmel_mci *host)
+{
+ if (host->debugfs_root) {
+ debugfs_remove(host->debugfs_completed_events);
+ debugfs_remove(host->debugfs_pending_events);
+ debugfs_remove(host->debugfs_req);
+ debugfs_remove(host->debugfs_regs);
+ debugfs_remove(host->debugfs_root);
+ host->debugfs_root = NULL;
+ }
+}
+#else
+static inline void atmci_init_debugfs(struct atmel_mci *host)
+{
+
+}
+
+static inline void atmci_cleanup_debugfs(struct atmel_mci *host)
+{
+
+}
+#endif /* CONFIG_DEBUG_FS */
+
+static inline unsigned int ns_to_clocks(struct atmel_mci *host,
+ unsigned int ns)
+{
+ return (ns * (host->bus_hz / 1000000) + 999) / 1000;
+}
+
+static void atmci_set_timeout(struct atmel_mci *host,
+ struct mmc_data *data)
+{
+ static unsigned dtomul_to_shift[] = {
+ 0, 4, 7, 8, 10, 12, 16, 20
+ };
+ unsigned timeout;
+ unsigned dtocyc;
+ unsigned dtomul;
+
+ timeout = ns_to_clocks(host, data->timeout_ns) + data->timeout_clks;
+
+ for (dtomul = 0; dtomul < 8; dtomul++) {
+ unsigned shift = dtomul_to_shift[dtomul];
+ dtocyc = (timeout + (1 << shift) - 1) >> shift;
+ if (dtocyc < 15)
+ break;
+ }
+
+ if (dtomul >= 8) {
+ dtomul = 7;
+ dtocyc = 15;
+ }
+
+ dev_dbg(&host->mmc->class_dev, "setting timeout to %u cycles\n",
+ dtocyc << dtomul_to_shift[dtomul]);
+ mci_writel(host, DTOR, (MCI_BF(DTOMUL, dtomul)
+ | MCI_BF(DTOCYC, dtocyc)));
+}
+
+/*
+ * Return mask with command flags to be enabled for this command.
+ */
+static u32 atmci_prepare_command(struct mmc_host *mmc,
+ struct mmc_command *cmd)
+{
+ u32 cmdr;
+
+ cmd->error = 0;
+
+ cmdr = MCI_BF(CMDNB, cmd->opcode);
+
+ if (cmd->flags & MMC_RSP_PRESENT) {
+ if (cmd->flags & MMC_RSP_136)
+ cmdr |= MCI_BF(RSPTYP, MCI_RSPTYP_136_BIT);
+ else
+ cmdr |= MCI_BF(RSPTYP, MCI_RSPTYP_48_BIT);
+ }
+
+ /*
+ * This should really be MAXLAT_5 for CMD2 and ACMD41, but
+ * it's too difficult to determine whether this is an ACMD or
+ * not. Better make it 64.
+ */
+ cmdr |= MCI_BIT(MAXLAT);
+
+ if (mmc->ios.bus_mode == MMC_BUSMODE_OPENDRAIN)
+ cmdr |= MCI_BIT(OPDCMD);
+
+ dev_dbg(&mmc->class_dev,
+ "cmd: op %02x arg %08x flags %08x, cmdflags %08lx\n",
+ cmd->opcode, cmd->arg, cmd->flags, (unsigned long)cmdr);
+
+ return cmdr;
+}
+
+static void atmci_start_data(struct atmel_mci *host)
+{
+ struct dma_slave_descriptor *desc, *_desc;
+ struct dma_chan *chan;
+
+ dev_vdbg(&host->mmc->class_dev, "submitting descriptors...\n");
+
+ /*
+ * Use the _safe() variant here because the might complete and
+ * get deleted from the list before we get around to the next
+ * entry. No need to lock since we're not modifying the list,
+ * and only entries we've submitted can be removed.
+ */
+ list_for_each_entry_safe(desc, _desc, &host->dma.data_descs,
+ client_node)
+ desc->txd.tx_submit(&desc->txd);
+
+ chan = host->dma.chan;
+
+ chan->device->device_issue_pending(chan);
+}
+
+static void atmci_start_command(struct atmel_mci *host,
+ struct mmc_command *cmd,
+ u32 cmd_flags)
+{
+ WARN_ON(host->cmd);
+ host->cmd = cmd;
+
+ mci_writel(host, ARGR, cmd->arg);
+ mci_writel(host, CMDR, cmd_flags);
+
+ if (cmd->data)
+ atmci_start_data(host);
+}
+
+static void send_stop_cmd(struct mmc_host *mmc, struct mmc_data *data)
+{
+ struct atmel_mci *host = mmc_priv(mmc);
+
+ atmci_start_command(host, data->stop, host->stop_cmdr);
+ mci_writel(host, IER, MCI_BIT(CMDRDY));
+}
+
+static void atmci_request_end(struct mmc_host *mmc, struct mmc_request *mrq)
+{
+ struct atmel_mci *host = mmc_priv(mmc);
+
+ WARN_ON(host->cmd || host->data);
+ host->mrq = NULL;
+
+ mmc_request_done(mmc, mrq);
+}
+
+static void atmci_dma_cleanup(struct atmel_mci *host)
+{
+ struct dma_slave_descriptor *desc, *_desc;
+ struct mmc_data *data = host->data;
+
+ dma_unmap_sg(&host->pdev->dev, data->sg, data->sg_len,
+ ((data->flags & MMC_DATA_WRITE)
+ ? DMA_TO_DEVICE : DMA_FROM_DEVICE));
+
+ /*
+ * REVISIT: Recycle these descriptors instead of handing them
+ * back to the controller.
+ */
+ list_for_each_entry_safe(desc, _desc, &host->dma.data_descs,
+ client_node) {
+ list_del(&desc->client_node);
+ async_tx_ack(&desc->txd);
+ }
+}
+
+static void atmci_stop_dma(struct atmel_mci *host)
+{
+ struct dma_chan *chan = host->dma.chan;
+
+ chan->device->device_terminate_all(chan);
+
+ atmci_dma_cleanup(host);
+}
+
+/* This function is called by the DMA driver from tasklet context. */
+static void atmci_dma_complete(void *arg)
+{
+ struct atmel_mci *host = arg;
+ struct mmc_data *data = host->data;
+
+ /* A short DMA transfer may complete before the command */
+ atmci_set_completed(host, EVENT_DMA_COMPLETE);
+ if (atmci_is_completed(host, EVENT_CMD_COMPLETE)
+ && data->stop
+ && !atmci_test_and_set_completed(host, EVENT_STOP_SENT))
+ send_stop_cmd(host->mmc, data);
+
+ atmci_dma_cleanup(host);
+
+ /*
+ * Regardless of what the documentation says, we have to wait
+ * for NOTBUSY even after block read operations.
+ *
+ * When the DMA transfer is complete, the controller may still
+ * be reading the CRC from the card, i.e. the data transfer is
+ * still in progress and we haven't seen all the potential
+ * error bits yet.
+ *
+ * The interrupt handler will schedule a different tasklet to
+ * finish things up when the data transfer is completely done.
+ *
+ * We may not complete the mmc request here anyway because the
+ * mmc layer may call back and cause us to violate the "don't
+ * submit new operations from the completion callback" rule of
+ * the dma engine framework.
+ */
+ mci_writel(host, IER, MCI_BIT(NOTBUSY));
+}
+
+/*
+ * Returns a mask of flags to be set in the command register when the
+ * command to start the transfer is to be sent.
+ */
+static u32 atmci_prepare_data(struct mmc_host *mmc, struct mmc_data *data)
+{
+ struct atmel_mci *host = mmc_priv(mmc);
+ struct dma_chan *chan = host->dma.chan;
+ struct dma_slave_descriptor *desc;
+ struct scatterlist *sg;
+ unsigned int sg_len;
+ unsigned int i;
+ int int_en;
+ u32 cmd_flags;
+
+ WARN_ON(host->data);
+ host->data = data;
+
+ atmci_set_timeout(host, data);
+ mci_writel(host, BLKR, (MCI_BF(BCNT, data->blocks)
+ | MCI_BF(BLKLEN, data->blksz)));
+
+ cmd_flags = MCI_BF(TRCMD, MCI_TRCMD_START_TRANS);
+ if (data->flags & MMC_DATA_STREAM)
+ cmd_flags |= MCI_BF(TRTYP, MCI_TRTYP_STREAM);
+ else if (data->blocks > 1)
+ cmd_flags |= MCI_BF(TRTYP, MCI_TRTYP_MULTI_BLOCK);
+ else
+ cmd_flags |= MCI_BF(TRTYP, MCI_TRTYP_BLOCK);
+
+ /* REVISIT: Try to cache pre-initialized descriptors */
+ int_en = 0;
+ dev_vdbg(&mmc->class_dev, "setting up descriptors...\n");
+ if (data->flags & MMC_DATA_READ) {
+ cmd_flags |= MCI_BIT(TRDIR);
+#ifdef POISON_READ_BUFFER
+ for_each_sg(data->sg, sg, data->sg_len, i) {
+ void *p = kmap(sg_page(sg));
+ memset(p + sg->offset, 0x55, sg->length);
+ kunmap(p);
+ }
+#endif
+ sg_len = dma_map_sg(&host->pdev->dev, data->sg,
+ data->sg_len, DMA_FROM_DEVICE);
+
+ for_each_sg(data->sg, sg, sg_len, i) {
+ if (i == sg_len - 1)
+ int_en = 1;
+
+ dev_vdbg(&mmc->class_dev, " addr %08x len %u (r)\n",
+ sg_dma_address(sg), sg_dma_len(sg));
+
+ desc = chan->device->device_prep_slave(chan,
+ sg_dma_len(sg), int_en);
+ desc->slave_set_width(desc, DMA_SLAVE_WIDTH_32BIT);
+ desc->slave_set_direction(desc, DMA_SLAVE_TO_MEMORY);
+ desc->txd.tx_set_dest(sg_dma_address(sg),
+ &desc->txd, 0);
+ list_add_tail(&desc->client_node,
+ &host->dma.data_descs);
+ }
+ } else {
+ sg_len = dma_map_sg(&host->pdev->dev, data->sg,
+ data->sg_len, DMA_TO_DEVICE);
+
+ for_each_sg(data->sg, sg, sg_len, i) {
+ if (i == sg_len - 1)
+ int_en = 1;
+
+ dev_vdbg(&mmc->class_dev, " addr %08x len %u (w)\n",
+ sg_dma_address(sg), sg_dma_len(sg));
+ desc = chan->device->device_prep_slave(chan,
+ sg_dma_len(sg), int_en);
+ desc->txd.callback = NULL;
+ desc->slave_set_width(desc, DMA_SLAVE_WIDTH_32BIT);
+ desc->slave_set_direction(desc, DMA_SLAVE_FROM_MEMORY);
+ desc->txd.tx_set_src(sg_dma_address(sg),
+ &desc->txd, 0);
+ list_add_tail(&desc->client_node,
+ &host->dma.data_descs);
+ }
+ }
+
+ /* Make sure we get notified when the last descriptor is done. */
+ desc = list_entry(host->dma.data_descs.prev,
+ struct dma_slave_descriptor, client_node);
+ desc->txd.callback = atmci_dma_complete;
+ desc->txd.callback_param = host;
+
+ return cmd_flags;
+}
+
+static void atmci_request(struct mmc_host *mmc, struct mmc_request *mrq)
+{
+ struct atmel_mci *host = mmc_priv(mmc);
+ struct mmc_data *data = mrq->data;
+ u32 iflags;
+ u32 cmdflags = 0;
+
+ iflags = mci_readl(host, IMR);
+ if (iflags)
+ dev_warn(&mmc->class_dev, "WARNING: IMR=0x%08x\n",
+ mci_readl(host, IMR));
+
+ WARN_ON(host->mrq != NULL);
+ host->mrq = mrq;
+ host->pending_events = 0;
+ host->completed_events = 0;
+
+ iflags = MCI_BIT(CMDRDY);
+ cmdflags = atmci_prepare_command(mmc, mrq->cmd);
+
+ if (mrq->stop) {
+ WARN_ON(!data);
+
+ host->stop_cmdr = atmci_prepare_command(mmc, mrq->stop);
+ host->stop_cmdr |= MCI_BF(TRCMD, MCI_TRCMD_STOP_TRANS);
+ if (!(data->flags & MMC_DATA_WRITE))
+ host->stop_cmdr |= MCI_BIT(TRDIR);
+ if (data->flags & MMC_DATA_STREAM)
+ host->stop_cmdr |= MCI_BF(TRTYP, MCI_TRTYP_STREAM);
+ else
+ host->stop_cmdr |= MCI_BF(TRTYP, MCI_TRTYP_MULTI_BLOCK);
+ }
+ if (data) {
+ cmdflags |= atmci_prepare_data(mmc, data);
+ iflags |= MCI_DATA_ERROR_FLAGS;
+ }
+
+ atmci_start_command(host, mrq->cmd, cmdflags);
+ mci_writel(host, IER, iflags);
+}
+
+static void atmci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
+{
+ struct atmel_mci *host = mmc_priv(mmc);
+ u32 mr;
+
+ if (ios->clock) {
+ u32 clkdiv;
+
+ /* Set clock rate */
+ clkdiv = host->bus_hz / (2 * ios->clock) - 1;
+ if (clkdiv > 255) {
+ dev_warn(&mmc->class_dev,
+ "clock %u too slow; using %lu\n",
+ ios->clock, host->bus_hz / (2 * 256));
+ clkdiv = 255;
+ }
+
+ mr = mci_readl(host, MR);
+ mr = MCI_BFINS(CLKDIV, clkdiv, mr)
+ | MCI_BIT(WRPROOF) | MCI_BIT(RDPROOF);
+ mci_writel(host, MR, mr);
+
+ /* Enable the MCI controller */
+ mci_writel(host, CR, MCI_BIT(MCIEN));
+ } else {
+ /* Disable the MCI controller */
+ mci_writel(host, CR, MCI_BIT(MCIDIS));
+ }
+
+ switch (ios->bus_width) {
+ case MMC_BUS_WIDTH_1:
+ mci_writel(host, SDCR, 0);
+ break;
+ case MMC_BUS_WIDTH_4:
+ mci_writel(host, SDCR, MCI_BIT(SDCBUS));
+ break;
+ }
+
+ switch (ios->power_mode) {
+ case MMC_POWER_ON:
+ /* Send init sequence (74 clock cycles) */
+ mci_writel(host, IDR, ~0UL);
+ mci_writel(host, CMDR, MCI_BF(SPCMD, MCI_SPCMD_INIT_CMD));
+ while (!(mci_readl(host, SR) & MCI_BIT(CMDRDY)))
+ cpu_relax();
+ break;
+ default:
+ /*
+ * TODO: None of the currently available AVR32-based
+ * boards allow MMC power to be turned off. Implement
+ * power control when this can be tested properly.
+ */
+ break;
+ }
+}
+
+static int atmci_get_ro(struct mmc_host *mmc)
+{
+ int read_only = 0;
+ struct atmel_mci *host = mmc_priv(mmc);
+
+ if (host->wp_pin >= 0) {
+ read_only = gpio_get_value(host->wp_pin);
+ dev_dbg(&mmc->class_dev, "card is %s\n",
+ read_only ? "read-only" : "read-write");
+ } else {
+ dev_dbg(&mmc->class_dev,
+ "no pin for checking read-only switch."
+ " Assuming write-enable.\n");
+ }
+
+ return read_only;
+}
+
+static struct mmc_host_ops atmci_ops = {
+ .request = atmci_request,
+ .set_ios = atmci_set_ios,
+ .get_ro = atmci_get_ro,
+};
+
+static void atmci_command_complete(struct atmel_mci *host,
+ struct mmc_command *cmd, u32 status)
+{
+ if (status & MCI_BIT(RTOE))
+ cmd->error = -ETIMEDOUT;
+ else if ((cmd->flags & MMC_RSP_CRC) && (status & MCI_BIT(RCRCE)))
+ cmd->error = -EILSEQ;
+ else if (status & (MCI_BIT(RINDE) | MCI_BIT(RDIRE) | MCI_BIT(RENDE)))
+ cmd->error = -EIO;
+
+ if (cmd->error) {
+ dev_dbg(&host->mmc->class_dev,
+ "command error: op=0x%x status=0x%08x\n",
+ cmd->opcode, status);
+
+ if (cmd->data) {
+ atmci_stop_dma(host);
+ mci_writel(host, IDR, MCI_BIT(NOTBUSY)
+ | MCI_DATA_ERROR_FLAGS);
+ host->data = NULL;
+ }
+ }
+}
+
+static void atmci_tasklet_func(unsigned long priv)
+{
+ struct mmc_host *mmc = (struct mmc_host *)priv;
+ struct atmel_mci *host = mmc_priv(mmc);
+ struct mmc_request *mrq = host->mrq;
+ struct mmc_data *data = host->data;
+
+ dev_vdbg(&mmc->class_dev,
+ "tasklet: pending/completed/mask %lx/%lx/%x\n",
+ host->pending_events, host->completed_events,
+ mci_readl(host, IMR));
+
+ if (atmci_test_and_clear_pending(host, EVENT_CMD_COMPLETE)) {
+ atmci_set_completed(host, EVENT_CMD_COMPLETE);
+ atmci_command_complete(host, mrq->cmd, host->cmd_status);
+ }
+ if (atmci_test_and_clear_pending(host, EVENT_STOP_COMPLETE)) {
+ atmci_set_completed(host, EVENT_STOP_COMPLETE);
+ atmci_command_complete(host, mrq->stop, host->stop_status);
+ }
+ if (atmci_test_and_clear_pending(host, EVENT_DATA_ERROR)) {
+ u32 status = host->data_status;
+
+ atmci_set_completed(host, EVENT_DATA_ERROR);
+ atmci_clear_pending(host, EVENT_DATA_COMPLETE);
+
+ atmci_stop_dma(host);
+
+ if (status & MCI_BIT(DCRCE)) {
+ dev_dbg(&mmc->class_dev, "data CRC error\n");
+ data->error = -EILSEQ;
+ } else if (status & MCI_BIT(DTOE)) {
+ dev_dbg(&mmc->class_dev, "data timeout error\n");
+ data->error = -ETIMEDOUT;
+ } else {
+ dev_dbg(&mmc->class_dev, "data FIFO error\n");
+ data->error = -EIO;
+ }
+ dev_dbg(&mmc->class_dev, "bytes xfered: %u\n",
+ data->bytes_xfered);
+
+ if (data->stop && atmci_test_and_set_completed(host,
+ EVENT_STOP_SENT))
+ /* TODO: Check if card is still present */
+ send_stop_cmd(host->mmc, data);
+
+ host->data = NULL;
+ }
+ if (atmci_test_and_clear_pending(host, EVENT_DATA_COMPLETE)) {
+ atmci_set_completed(host, EVENT_DATA_COMPLETE);
+ data->bytes_xfered = data->blocks * data->blksz;
+ host->data = NULL;
+ }
+ if (atmci_test_and_clear_pending(host, EVENT_CARD_DETECT)) {
+ /* Reset controller if card is gone */
+ if (!host->present) {
+ mci_writel(host, CR, MCI_BIT(SWRST));
+ mci_writel(host, IDR, ~0UL);
+ mci_writel(host, CR, MCI_BIT(MCIEN));
+ }
+
+ /* Clean up queue if present */
+ if (mrq) {
+ if (!atmci_is_completed(host, EVENT_CMD_COMPLETE))
+ mrq->cmd->error = -EIO;
+
+ if (mrq->data && !atmci_is_completed(host,
+ EVENT_DATA_COMPLETE)
+ && !atmci_is_completed(host,
+ EVENT_DATA_ERROR)) {
+ atmci_stop_dma(host);
+ mrq->data->error = -EIO;
+ host->data = NULL;
+ }
+ if (mrq->stop && !atmci_is_completed(host,
+ EVENT_STOP_COMPLETE))
+ mrq->stop->error = -EIO;
+
+ host->cmd = NULL;
+ atmci_request_end(mmc, mrq);
+ }
+ mmc_detect_change(host->mmc, msecs_to_jiffies(100));
+ }
+
+ if (host->mrq && !host->cmd && !host->data)
+ atmci_request_end(mmc, host->mrq);
+}
+
+static void atmci_cmd_interrupt(struct mmc_host *mmc, u32 status)
+{
+ struct atmel_mci *host = mmc_priv(mmc);
+ struct mmc_command *cmd = host->cmd;
+
+ /*
+ * Read the response now so that we're free to send a new
+ * command immediately.
+ */
+ cmd->resp[0] = mci_readl(host, RSPR);
+ cmd->resp[1] = mci_readl(host, RSPR);
+ cmd->resp[2] = mci_readl(host, RSPR);
+ cmd->resp[3] = mci_readl(host, RSPR);
+
+ mci_writel(host, IDR, MCI_BIT(CMDRDY));
+ host->cmd = NULL;
+
+ if (atmci_is_completed(host, EVENT_STOP_SENT)) {
+ host->stop_status = status;
+ atmci_set_pending(host, EVENT_STOP_COMPLETE);
+ } else {
+ struct mmc_request *mrq = host->mrq;
+
+ if (mrq->stop && atmci_is_completed(host, EVENT_DMA_COMPLETE)
+ && !atmci_test_and_set_completed(host,
+ EVENT_STOP_SENT))
+ send_stop_cmd(host->mmc, mrq->data);
+ host->cmd_status = status;
+ atmci_set_pending(host, EVENT_CMD_COMPLETE);
+ }
+
+ tasklet_schedule(&host->tasklet);
+}
+
+static irqreturn_t atmci_interrupt(int irq, void *dev_id)
+{
+ struct mmc_host *mmc = dev_id;
+ struct atmel_mci *host = mmc_priv(mmc);
+ u32 status, mask, pending;
+
+ spin_lock(&mmc->lock);
+
+ status = mci_readl(host, SR);
+ mask = mci_readl(host, IMR);
+ pending = status & mask;
+
+ do {
+ if (pending & MCI_DATA_ERROR_FLAGS) {
+ mci_writel(host, IDR, (MCI_BIT(NOTBUSY)
+ | MCI_DATA_ERROR_FLAGS));
+ host->data_status = status;
+ atmci_set_pending(host, EVENT_DATA_ERROR);
+ tasklet_schedule(&host->tasklet);
+ break;
+ }
+ if (pending & MCI_BIT(CMDRDY))
+ atmci_cmd_interrupt(mmc, status);
+ if (pending & MCI_BIT(NOTBUSY)) {
+ mci_writel(host, IDR, (MCI_BIT(NOTBUSY)
+ | MCI_DATA_ERROR_FLAGS));
+ atmci_set_pending(host, EVENT_DATA_COMPLETE);
+ tasklet_schedule(&host->tasklet);
+ }
+
+ status = mci_readl(host, SR);
+ mask = mci_readl(host, IMR);
+ pending = status & mask;
+ } while (pending);
+
+ spin_unlock(&mmc->lock);
+
+ return IRQ_HANDLED;
+}
+
+static irqreturn_t atmci_detect_change(int irq, void *dev_id)
+{
+ struct mmc_host *mmc = dev_id;
+ struct atmel_mci *host = mmc_priv(mmc);
+
+ int present = !gpio_get_value(irq_to_gpio(irq));
+
+ if (present != host->present) {
+ dev_dbg(&mmc->class_dev, "card %s\n",
+ present ? "inserted" : "removed");
+ host->present = present;
+ atmci_set_pending(host, EVENT_CARD_DETECT);
+ tasklet_schedule(&host->tasklet);
+ }
+ return IRQ_HANDLED;
+}
+
+static enum dma_state_client atmci_dma_event(struct dma_client *client,
+ struct dma_chan *chan, enum dma_state state)
+{
+ struct atmel_mci *host;
+ enum dma_state_client ret = DMA_NAK;
+
+ host = dma_client_to_atmel_mci(client);
+
+ switch (state) {
+ case DMA_RESOURCE_AVAILABLE:
+ if (!host->dma.chan) {
+ dev_dbg(&host->pdev->dev, "Got channel %s\n",
+ chan->dev.bus_id);
+ host->dma.chan = chan;
+ ret = DMA_ACK;
+ }
+ break;
+
+ case DMA_RESOURCE_REMOVED:
+ if (host->dma.chan == chan) {
+ dev_dbg(&host->pdev->dev, "Lost channel %s\n",
+ chan->dev.bus_id);
+ host->dma.chan = NULL;
+ ret = DMA_ACK;
+ }
+ break;
+
+ default:
+ break;
+ }
+
+ return ret;
+}
+
+static int __init atmci_probe(struct platform_device *pdev)
+{
+ struct mci_platform_data *pdata;
+ struct atmel_mci *host;
+ struct mmc_host *mmc;
+ struct resource *regs;
+ struct dma_chan *chan;
+ int irq;
+ int ret;
+
+ regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!regs)
+ return -ENXIO;
+ pdata = pdev->dev.platform_data;
+ if (!pdata)
+ return -ENXIO;
+ irq = platform_get_irq(pdev, 0);
+ if (irq < 0)
+ return irq;
+
+ mmc = mmc_alloc_host(sizeof(struct atmel_mci), &pdev->dev);
+ if (!mmc)
+ return -ENOMEM;
+
+ host = mmc_priv(mmc);
+ host->pdev = pdev;
+ host->mmc = mmc;
+ host->detect_pin = pdata->detect_pin;
+ host->wp_pin = pdata->wp_pin;
+ INIT_LIST_HEAD(&host->dma.data_descs);
+
+ host->mck = clk_get(&pdev->dev, "mci_clk");
+ if (IS_ERR(host->mck)) {
+ ret = PTR_ERR(host->mck);
+ goto err_clk_get;
+ }
+ clk_enable(host->mck);
+
+ ret = -ENOMEM;
+ host->regs = ioremap(regs->start, regs->end - regs->start + 1);
+ if (!host->regs)
+ goto err_ioremap;
+
+ mci_writel(host, CR, MCI_BIT(SWRST));
+ mci_writel(host, IDR, ~0UL);
+
+ host->bus_hz = clk_get_rate(host->mck);
+ host->mapbase = regs->start;
+
+ mmc->ops = &atmci_ops;
+ mmc->f_min = (host->bus_hz + 511) / 512;
+ mmc->f_max = min((unsigned int)(host->bus_hz / 2), fmax);
+ mmc->ocr_avail = MMC_VDD_32_33 | MMC_VDD_33_34;
+ mmc->caps |= MMC_CAP_4_BIT_DATA;
+
+ tasklet_init(&host->tasklet, atmci_tasklet_func, (unsigned long)mmc);
+
+ ret = request_irq(irq, atmci_interrupt, 0, "mmci", mmc);
+ if (ret)
+ goto err_request_irq;
+
+ /* Try to grab a DMA channel */
+ host->dma.client.event_callback = atmci_dma_event;
+ dma_cap_set(DMA_SLAVE, host->dma.client.cap_mask);
+ dma_async_client_register(&host->dma.client);
+ dma_async_client_chan_request(&host->dma.client);
+
+ chan = host->dma.chan;
+ if (!chan) {
+ dev_dbg(&mmc->class_dev, "no DMA channels available\n");
+ ret = -ENODEV;
+ goto err_dma_chan;
+ }
+
+ /* FIXME: The DMA channel may disappear... */
+ chan->device->device_set_slave(chan,
+ regs->start + MCI_RDR, pdata->rx_periph_id,
+ regs->start + MCI_TDR, pdata->tx_periph_id);
+
+ /* Assume card is present if we don't have a detect pin */
+ host->present = 1;
+ if (host->detect_pin >= 0) {
+ if (gpio_request(host->detect_pin, "mmc_detect")) {
+ dev_dbg(&mmc->class_dev, "no detect pin available\n");
+ host->detect_pin = -1;
+ } else {
+ host->present = !gpio_get_value(host->detect_pin);
+ }
+ }
+ if (host->wp_pin >= 0) {
+ if (gpio_request(host->wp_pin, "mmc_wp")) {
+ dev_dbg(&mmc->class_dev, "no WP pin available\n");
+ host->wp_pin = -1;
+ }
+ }
+
+ platform_set_drvdata(pdev, host);
+
+ mmc_add_host(mmc);
+
+ if (host->detect_pin >= 0) {
+ ret = request_irq(gpio_to_irq(host->detect_pin),
+ atmci_detect_change,
+ IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING,
+ DRIVER_NAME, mmc);
+ if (ret) {
+ dev_dbg(&mmc->class_dev,
+ "could not request IRQ %d for detect pin\n",
+ gpio_to_irq(host->detect_pin));
+ gpio_free(host->detect_pin);
+ host->detect_pin = -1;
+ }
+ }
+
+ dev_info(&mmc->class_dev,
+ "Atmel MCI controller at 0x%08lx irq %d dma %s\n",
+ host->mapbase, irq, chan->dev.bus_id);
+
+ atmci_init_debugfs(host);
+
+ return 0;
+
+err_dma_chan:
+ free_irq(irq, mmc);
+err_request_irq:
+ iounmap(host->regs);
+err_ioremap:
+ clk_disable(host->mck);
+ clk_put(host->mck);
+err_clk_get:
+ mmc_free_host(mmc);
+ return ret;
+}
+
+static int __exit atmci_remove(struct platform_device *pdev)
+{
+ struct atmel_mci *host = platform_get_drvdata(pdev);
+
+ platform_set_drvdata(pdev, NULL);
+
+ if (host) {
+ atmci_cleanup_debugfs(host);
+
+ if (host->detect_pin >= 0) {
+ free_irq(gpio_to_irq(host->detect_pin), host->mmc);
+ cancel_delayed_work(&host->mmc->detect);
+ gpio_free(host->detect_pin);
+ }
+
+ mmc_remove_host(host->mmc);
+
+ mci_writel(host, IDR, ~0UL);
+ mci_writel(host, CR, MCI_BIT(MCIDIS));
+ mci_readl(host, SR);
+
+ dma_async_client_unregister(&host->dma.client);
+
+ if (host->wp_pin >= 0)
+ gpio_free(host->wp_pin);
+
+ free_irq(platform_get_irq(pdev, 0), host->mmc);
+ iounmap(host->regs);
+
+ clk_disable(host->mck);
+ clk_put(host->mck);
+
+ mmc_free_host(host->mmc);
+ }
+ return 0;
+}
+
+static struct platform_driver atmci_driver = {
+ .remove = __exit_p(atmci_remove),
+ .driver = {
+ .name = DRIVER_NAME,
+ },
+};
+
+static int __init atmci_init(void)
+{
+ return platform_driver_probe(&atmci_driver, atmci_probe);
+}
+
+static void __exit atmci_exit(void)
+{
+ platform_driver_unregister(&atmci_driver);
+}
+
+module_init(atmci_init);
+module_exit(atmci_exit);
+
+MODULE_DESCRIPTION("Atmel Multimedia Card Interface driver");
+MODULE_LICENSE("GPL");
diff --git a/drivers/mmc/host/atmel-mci.h b/drivers/mmc/host/atmel-mci.h
new file mode 100644
index 0000000..60d15c4
--- /dev/null
+++ b/drivers/mmc/host/atmel-mci.h
@@ -0,0 +1,192 @@
+/*
+ * Atmel MultiMedia Card Interface driver
+ *
+ * Copyright (C) 2004-2006 Atmel Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#ifndef __DRIVERS_MMC_ATMEL_MCI_H__
+#define __DRIVERS_MMC_ATMEL_MCI_H__
+
+/* MCI register offsets */
+#define MCI_CR 0x0000
+#define MCI_MR 0x0004
+#define MCI_DTOR 0x0008
+#define MCI_SDCR 0x000c
+#define MCI_ARGR 0x0010
+#define MCI_CMDR 0x0014
+#define MCI_BLKR 0x0018
+#define MCI_RSPR 0x0020
+#define MCI_RSPR1 0x0024
+#define MCI_RSPR2 0x0028
+#define MCI_RSPR3 0x002c
+#define MCI_RDR 0x0030
+#define MCI_TDR 0x0034
+#define MCI_SR 0x0040
+#define MCI_IER 0x0044
+#define MCI_IDR 0x0048
+#define MCI_IMR 0x004c
+
+/* Bitfields in CR */
+#define MCI_MCIEN_OFFSET 0
+#define MCI_MCIEN_SIZE 1
+#define MCI_MCIDIS_OFFSET 1
+#define MCI_MCIDIS_SIZE 1
+#define MCI_PWSEN_OFFSET 2
+#define MCI_PWSEN_SIZE 1
+#define MCI_PWSDIS_OFFSET 3
+#define MCI_PWSDIS_SIZE 1
+#define MCI_SWRST_OFFSET 7
+#define MCI_SWRST_SIZE 1
+
+/* Bitfields in MR */
+#define MCI_CLKDIV_OFFSET 0
+#define MCI_CLKDIV_SIZE 8
+#define MCI_PWSDIV_OFFSET 8
+#define MCI_PWSDIV_SIZE 3
+#define MCI_RDPROOF_OFFSET 11
+#define MCI_RDPROOF_SIZE 1
+#define MCI_WRPROOF_OFFSET 12
+#define MCI_WRPROOF_SIZE 1
+#define MCI_DMAPADV_OFFSET 14
+#define MCI_DMAPADV_SIZE 1
+#define MCI_BLKLEN_OFFSET 16
+#define MCI_BLKLEN_SIZE 16
+
+/* Bitfields in DTOR */
+#define MCI_DTOCYC_OFFSET 0
+#define MCI_DTOCYC_SIZE 4
+#define MCI_DTOMUL_OFFSET 4
+#define MCI_DTOMUL_SIZE 3
+
+/* Bitfields in SDCR */
+#define MCI_SDCSEL_OFFSET 0
+#define MCI_SDCSEL_SIZE 4
+#define MCI_SDCBUS_OFFSET 7
+#define MCI_SDCBUS_SIZE 1
+
+/* Bitfields in ARGR */
+#define MCI_ARG_OFFSET 0
+#define MCI_ARG_SIZE 32
+
+/* Bitfields in CMDR */
+#define MCI_CMDNB_OFFSET 0
+#define MCI_CMDNB_SIZE 6
+#define MCI_RSPTYP_OFFSET 6
+#define MCI_RSPTYP_SIZE 2
+#define MCI_SPCMD_OFFSET 8
+#define MCI_SPCMD_SIZE 3
+#define MCI_OPDCMD_OFFSET 11
+#define MCI_OPDCMD_SIZE 1
+#define MCI_MAXLAT_OFFSET 12
+#define MCI_MAXLAT_SIZE 1
+#define MCI_TRCMD_OFFSET 16
+#define MCI_TRCMD_SIZE 2
+#define MCI_TRDIR_OFFSET 18
+#define MCI_TRDIR_SIZE 1
+#define MCI_TRTYP_OFFSET 19
+#define MCI_TRTYP_SIZE 2
+
+/* Bitfields in BLKR */
+#define MCI_BCNT_OFFSET 0
+#define MCI_BCNT_SIZE 16
+
+/* Bitfields in RSPRn */
+#define MCI_RSP_OFFSET 0
+#define MCI_RSP_SIZE 32
+
+/* Bitfields in SR/IER/IDR/IMR */
+#define MCI_CMDRDY_OFFSET 0
+#define MCI_CMDRDY_SIZE 1
+#define MCI_RXRDY_OFFSET 1
+#define MCI_RXRDY_SIZE 1
+#define MCI_TXRDY_OFFSET 2
+#define MCI_TXRDY_SIZE 1
+#define MCI_BLKE_OFFSET 3
+#define MCI_BLKE_SIZE 1
+#define MCI_DTIP_OFFSET 4
+#define MCI_DTIP_SIZE 1
+#define MCI_NOTBUSY_OFFSET 5
+#define MCI_NOTBUSY_SIZE 1
+#define MCI_ENDRX_OFFSET 6
+#define MCI_ENDRX_SIZE 1
+#define MCI_ENDTX_OFFSET 7
+#define MCI_ENDTX_SIZE 1
+#define MCI_RXBUFF_OFFSET 14
+#define MCI_RXBUFF_SIZE 1
+#define MCI_TXBUFE_OFFSET 15
+#define MCI_TXBUFE_SIZE 1
+#define MCI_RINDE_OFFSET 16
+#define MCI_RINDE_SIZE 1
+#define MCI_RDIRE_OFFSET 17
+#define MCI_RDIRE_SIZE 1
+#define MCI_RCRCE_OFFSET 18
+#define MCI_RCRCE_SIZE 1
+#define MCI_RENDE_OFFSET 19
+#define MCI_RENDE_SIZE 1
+#define MCI_RTOE_OFFSET 20
+#define MCI_RTOE_SIZE 1
+#define MCI_DCRCE_OFFSET 21
+#define MCI_DCRCE_SIZE 1
+#define MCI_DTOE_OFFSET 22
+#define MCI_DTOE_SIZE 1
+#define MCI_OVRE_OFFSET 30
+#define MCI_OVRE_SIZE 1
+#define MCI_UNRE_OFFSET 31
+#define MCI_UNRE_SIZE 1
+
+/* Constants for DTOMUL */
+#define MCI_DTOMUL_1_CYCLE 0
+#define MCI_DTOMUL_16_CYCLES 1
+#define MCI_DTOMUL_128_CYCLES 2
+#define MCI_DTOMUL_256_CYCLES 3
+#define MCI_DTOMUL_1024_CYCLES 4
+#define MCI_DTOMUL_4096_CYCLES 5
+#define MCI_DTOMUL_65536_CYCLES 6
+#define MCI_DTOMUL_1048576_CYCLES 7
+
+/* Constants for RSPTYP */
+#define MCI_RSPTYP_NO_RESP 0
+#define MCI_RSPTYP_48_BIT 1
+#define MCI_RSPTYP_136_BIT 2
+
+/* Constants for SPCMD */
+#define MCI_SPCMD_NO_SPEC_CMD 0
+#define MCI_SPCMD_INIT_CMD 1
+#define MCI_SPCMD_SYNC_CMD 2
+#define MCI_SPCMD_INT_CMD 4
+#define MCI_SPCMD_INT_RESP 5
+
+/* Constants for TRCMD */
+#define MCI_TRCMD_NO_TRANS 0
+#define MCI_TRCMD_START_TRANS 1
+#define MCI_TRCMD_STOP_TRANS 2
+
+/* Constants for TRTYP */
+#define MCI_TRTYP_BLOCK 0
+#define MCI_TRTYP_MULTI_BLOCK 1
+#define MCI_TRTYP_STREAM 2
+
+/* Bit manipulation macros */
+#define MCI_BIT(name) \
+ (1 << MCI_##name##_OFFSET)
+#define MCI_BF(name,value) \
+ (((value) & ((1 << MCI_##name##_SIZE) - 1)) \
+ << MCI_##name##_OFFSET)
+#define MCI_BFEXT(name,value) \
+ (((value) >> MCI_##name##_OFFSET) \
+ & ((1 << MCI_##name##_SIZE) - 1))
+#define MCI_BFINS(name,value,old) \
+ (((old) & ~(((1 << MCI_##name##_SIZE) - 1) \
+ << MCI_##name##_OFFSET)) \
+ | MCI_BF(name,value))
+
+/* Register access macros */
+#define mci_readl(port,reg) \
+ __raw_readl((port)->regs + MCI_##reg)
+#define mci_writel(port,reg,value) \
+ __raw_writel((value), (port)->regs + MCI_##reg)
+
+#endif /* __DRIVERS_MMC_ATMEL_MCI_H__ */
diff --git a/include/asm-avr32/arch-at32ap/board.h b/include/asm-avr32/arch-at32ap/board.h
index d6993a6..665682e 100644
--- a/include/asm-avr32/arch-at32ap/board.h
+++ b/include/asm-avr32/arch-at32ap/board.h
@@ -66,7 +66,15 @@ struct platform_device *
at32_add_device_ssc(unsigned int id, unsigned int flags);
struct platform_device *at32_add_device_twi(unsigned int id);
-struct platform_device *at32_add_device_mci(unsigned int id);
+
+struct mci_platform_data {
+ unsigned int tx_periph_id;
+ unsigned int rx_periph_id;
+ int detect_pin;
+ int wp_pin;
+};
+struct platform_device *
+at32_add_device_mci(unsigned int id, struct mci_platform_data *data);
struct platform_device *at32_add_device_ac97c(unsigned int id);
struct platform_device *at32_add_device_abdac(unsigned int id);
--
1.5.3.4
^ permalink raw reply related [flat|nested] 11+ messages in thread
* Re: [RFC 4/4] Atmel MCI: Driver for Atmel on-chip MMC controllers
2007-11-23 12:20 ` [RFC 4/4] Atmel MCI: Driver for Atmel on-chip MMC controllers Haavard Skinnemoen
@ 2007-11-24 17:00 ` Pierre Ossman
2007-11-24 18:16 ` Haavard Skinnemoen
0 siblings, 1 reply; 11+ messages in thread
From: Pierre Ossman @ 2007-11-24 17:00 UTC (permalink / raw)
To: Haavard Skinnemoen
Cc: linux-kernel, Shannon Nelson, Dan Williams, David Brownell,
kernel, linux-arm-kernel, Haavard Skinnemoen
On Fri, 23 Nov 2007 13:20:13 +0100
Haavard Skinnemoen <hskinnemoen@atmel.com> wrote:
> This is a driver for the MMC controller on the AP7000 chips from
> Atmel. It should in theory work on AT91 systems too with some
> tweaking, but since the DMA interface is quite different, it's not
> entirely clear if it's worth it.
>
> This driver has been around for a while in BSPs and kernel sources
> provided by Atmel, but this particular version uses the generic DMA
> Engine framework (with the slave extensions) instead of an
> avr32-only DMA controller framework.
>
> Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
Why didn't I get a cc? Don't you love me any more? :'(
> ---
> arch/avr32/boards/atngw100/setup.c | 6 +
> arch/avr32/boards/atstk1000/atstk1002.c | 3 +
> arch/avr32/mach-at32ap/at32ap7000.c | 31 +-
> drivers/mmc/host/Kconfig | 10 +
> drivers/mmc/host/Makefile | 1 +
> drivers/mmc/host/atmel-mci.c | 1170 +++++++++++++++++++++++++++++++
> drivers/mmc/host/atmel-mci.h | 192 +++++
> include/asm-avr32/arch-at32ap/board.h | 10 +-
> 8 files changed, 1417 insertions(+), 6 deletions(-)
> create mode 100644 drivers/mmc/host/atmel-mci.c
> create mode 100644 drivers/mmc/host/atmel-mci.h
>
Could you add a note to MAINTAINERS as well?
> diff --git a/drivers/mmc/host/Kconfig b/drivers/mmc/host/Kconfig
> index 5fef678..687cf8b 100644
> --- a/drivers/mmc/host/Kconfig
> +++ b/drivers/mmc/host/Kconfig
> @@ -91,6 +91,16 @@ config MMC_AT91
>
> If unsure, say N.
>
> +config MMC_ATMELMCI
> + tristate "Atmel Multimedia Card Interface support"
> + depends on AVR32 && DMA_ENGINE
> + help
> + This selects the Atmel Multimedia Card Interface. If you have
> + a AT91 (ARM) or AT32 (AVR32) platform with a Multimedia Card
> + slot, say Y or M here.
> +
> + If unsure, say N.
> +
> config MMC_IMX
> tristate "Motorola i.MX Multimedia Card Interface support"
> depends on ARCH_IMX
Now this gets a bit confusing as we'll have two drivers for AT91. Any status report on merging these?
I can accept having two drivers (for a while at least), but the Kconfig help texts should explain the sordid details.
> +
> +/* Those printks take an awful lot of time... */
> +#ifndef DEBUG
> +static unsigned int fmax = 15000000U;
> +#else
> +static unsigned int fmax = 1000000U;
> +#endif
> +module_param(fmax, uint, 0444);
> +MODULE_PARM_DESC(fmax, "Max frequency in Hz of the MMC bus clock");
> +
Why is this needed and is it perhaps something that can be moved to the MMC core?
> +
> +static int req_dbg_open(struct inode *inode, struct file *file)
> +{
This also looks like something that can be made general.
> +
> + if (mmc->ios.bus_mode == MMC_BUSMODE_OPENDRAIN)
> + cmdr |= MCI_BIT(OPDCMD);
> +
> + dev_dbg(&mmc->class_dev,
> + "cmd: op %02x arg %08x flags %08x, cmdflags %08lx\n",
> + cmd->opcode, cmd->arg, cmd->flags, (unsigned long)cmdr);
> +
The debug output in the core should make this redundant.
> +
> +static void atmci_request(struct mmc_host *mmc, struct mmc_request *mrq)
> +{
I seem to recall that atmci couldn't currently handle transfers that weren't a multiple of four. Could you please add a check for this and fail the request with -EINVAL when that happens?
> +
> +static void atmci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
> +{
> + struct atmel_mci *host = mmc_priv(mmc);
> + u32 mr;
> +
> + if (ios->clock) {
> + u32 clkdiv;
> +
> + /* Set clock rate */
> + clkdiv = host->bus_hz / (2 * ios->clock) - 1;
> + if (clkdiv > 255) {
> + dev_warn(&mmc->class_dev,
> + "clock %u too slow; using %lu\n",
> + ios->clock, host->bus_hz / (2 * 256));
> + clkdiv = 255;
> + }
> +
> + mr = mci_readl(host, MR);
> + mr = MCI_BFINS(CLKDIV, clkdiv, mr)
> + | MCI_BIT(WRPROOF) | MCI_BIT(RDPROOF);
> + mci_writel(host, MR, mr);
> +
> + /* Enable the MCI controller */
> + mci_writel(host, CR, MCI_BIT(MCIEN));
> + } else {
> + /* Disable the MCI controller */
> + mci_writel(host, CR, MCI_BIT(MCIDIS));
> + }
> +
I hope "disable" here doesn't power down the card, as that would be incorrect.
> +
> + if (status & MCI_BIT(DCRCE)) {
> + dev_dbg(&mmc->class_dev, "data CRC error\n");
> + data->error = -EILSEQ;
> + } else if (status & MCI_BIT(DTOE)) {
> + dev_dbg(&mmc->class_dev, "data timeout error\n");
> + data->error = -ETIMEDOUT;
> + } else {
> + dev_dbg(&mmc->class_dev, "data FIFO error\n");
> + data->error = -EIO;
> + }
> + dev_dbg(&mmc->class_dev, "bytes xfered: %u\n",
> + data->bytes_xfered);
> +
The debug output here is already provided by the MMC core.
> +
> +static int __exit atmci_remove(struct platform_device *pdev)
> +{
> + struct atmel_mci *host = platform_get_drvdata(pdev);
> +
> + platform_set_drvdata(pdev, NULL);
> +
> + if (host) {
> + atmci_cleanup_debugfs(host);
> +
> + if (host->detect_pin >= 0) {
> + free_irq(gpio_to_irq(host->detect_pin), host->mmc);
> + cancel_delayed_work(&host->mmc->detect);
Not for driver poking. Hands off! :)
Rgds
--
-- Pierre Ossman
Linux kernel, MMC maintainer http://www.kernel.org
PulseAudio, core developer http://pulseaudio.org
rdesktop, core developer http://www.rdesktop.org
^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [RFC 4/4] Atmel MCI: Driver for Atmel on-chip MMC controllers
2007-11-24 17:00 ` Pierre Ossman
@ 2007-11-24 18:16 ` Haavard Skinnemoen
2007-11-24 18:48 ` David Brownell
0 siblings, 1 reply; 11+ messages in thread
From: Haavard Skinnemoen @ 2007-11-24 18:16 UTC (permalink / raw)
To: Pierre Ossman
Cc: linux-kernel, Shannon Nelson, Dan Williams, David Brownell,
kernel, linux-arm-kernel
On Sat, 24 Nov 2007 18:00:23 +0100
Pierre Ossman <drzeus-list@drzeus.cx> wrote:
> On Fri, 23 Nov 2007 13:20:13 +0100
> Haavard Skinnemoen <hskinnemoen@atmel.com> wrote:
>
> > This is a driver for the MMC controller on the AP7000 chips from
> > Atmel. It should in theory work on AT91 systems too with some
> > tweaking, but since the DMA interface is quite different, it's not
> > entirely clear if it's worth it.
> >
> > This driver has been around for a while in BSPs and kernel sources
> > provided by Atmel, but this particular version uses the generic DMA
> > Engine framework (with the slave extensions) instead of an
> > avr32-only DMA controller framework.
> >
> > Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
>
> Why didn't I get a cc? Don't you love me any more? :'(
Sorry, I didn't really mean to submit it for inclusion yet, as I
explained in the first mail in the series. I probably should have left
out the signoff to make this clearer.
Thanks for the feedback anyway.
> Could you add a note to MAINTAINERS as well?
Yes, I intend to do that in the final version.
> > diff --git a/drivers/mmc/host/Kconfig b/drivers/mmc/host/Kconfig
> > index 5fef678..687cf8b 100644
> > --- a/drivers/mmc/host/Kconfig
> > +++ b/drivers/mmc/host/Kconfig
> > @@ -91,6 +91,16 @@ config MMC_AT91
> >
> > If unsure, say N.
> >
> > +config MMC_ATMELMCI
> > + tristate "Atmel Multimedia Card Interface support"
> > + depends on AVR32 && DMA_ENGINE
> > + help
> > + This selects the Atmel Multimedia Card Interface. If you
> > have
> > + a AT91 (ARM) or AT32 (AVR32) platform with a Multimedia
> > Card
> > + slot, say Y or M here.
> > +
> > + If unsure, say N.
> > +
> > config MMC_IMX
> > tristate "Motorola i.MX Multimedia Card Interface support"
> > depends on ARCH_IMX
>
> Now this gets a bit confusing as we'll have two drivers for AT91. Any
> status report on merging these?
I haven't really started working on that I'm afraid. I imagine the
parts dealing with data transfer will have to be completely separate
due to the differences in the DMA interface. Probably the interrupt
handler as well, unless we're willing to live with a few #ifdefs in it.
> I can accept having two drivers (for a while at least), but the
> Kconfig help texts should explain the sordid details.
Yeah, the help text is indeed confusing. I'll update it.
> > +
> > +/* Those printks take an awful lot of time... */
> > +#ifndef DEBUG
> > +static unsigned int fmax = 15000000U;
> > +#else
> > +static unsigned int fmax = 1000000U;
> > +#endif
> > +module_param(fmax, uint, 0444);
> > +MODULE_PARM_DESC(fmax, "Max frequency in Hz of the MMC bus clock");
> > +
>
> Why is this needed and is it perhaps something that can be moved to
> the MMC core?
We used to have lots of problems with overruns and underruns and those
parameters were useful to limit the transfer rate. Now that the RDPROOF
and WRPROOF bits seem to have taken care of these problems for good, I
guess we can remove this parameter.
> > +
> > +static int req_dbg_open(struct inode *inode, struct file *file)
> > +{
>
> This also looks like something that can be made general.
Yeah, could be. I'll look into it.
> > +
> > + if (mmc->ios.bus_mode == MMC_BUSMODE_OPENDRAIN)
> > + cmdr |= MCI_BIT(OPDCMD);
> > +
> > + dev_dbg(&mmc->class_dev,
> > + "cmd: op %02x arg %08x flags %08x, cmdflags
> > %08lx\n",
> > + cmd->opcode, cmd->arg, cmd->flags, (unsigned
> > long)cmdr); +
>
> The debug output in the core should make this redundant.
Yes, most of it is redundant, but the hardware register dump might
still make sense, but it should probably be turned into a dev_vdbg().
> > +
> > +static void atmci_request(struct mmc_host *mmc, struct mmc_request
> > *mrq) +{
>
> I seem to recall that atmci couldn't currently handle transfers that
> weren't a multiple of four. Could you please add a check for this and
> fail the request with -EINVAL when that happens?
Yeah, although I want to fix that before submitting the final version.
The hardware has a special "byte mode" which will be slow, but it
should work.
> > + /* Enable the MCI controller */
> > + mci_writel(host, CR, MCI_BIT(MCIEN));
> > + } else {
> > + /* Disable the MCI controller */
> > + mci_writel(host, CR, MCI_BIT(MCIDIS));
> > + }
> > +
>
> I hope "disable" here doesn't power down the card, as that would be
> incorrect.
No, it just stops the clock. I suppose we could use clk_disable()
instead of resetting the controller, but I don't think there's any
controller state we really care about at this point anyway.
> > + dev_dbg(&mmc->class_dev, "bytes xfered: %u\n",
> > + data->bytes_xfered);
> > +
>
> The debug output here is already provided by the MMC core.
Indeed. I'll remove it.
> > +
> > +static int __exit atmci_remove(struct platform_device *pdev)
> > +{
> > + struct atmel_mci *host = platform_get_drvdata(pdev);
> > +
> > + platform_set_drvdata(pdev, NULL);
> > +
> > + if (host) {
> > + atmci_cleanup_debugfs(host);
> > +
> > + if (host->detect_pin >= 0) {
> > + free_irq(gpio_to_irq(host->detect_pin),
> > host->mmc);
> > + cancel_delayed_work(&host->mmc->detect);
>
> Not for driver poking. Hands off! :)
Ah. I think this solved some kind of oops-on-card-removal thing at some
point, but I'll try to remove it and see what happens.
Hmm...no, that can't be the case. I have to admit I don't quite
remember why we put that there.
Haavard
^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [RFC 4/4] Atmel MCI: Driver for Atmel on-chip MMC controllers
2007-11-24 18:16 ` Haavard Skinnemoen
@ 2007-11-24 18:48 ` David Brownell
2007-11-24 19:24 ` Haavard Skinnemoen
0 siblings, 1 reply; 11+ messages in thread
From: David Brownell @ 2007-11-24 18:48 UTC (permalink / raw)
To: Haavard Skinnemoen
Cc: Pierre Ossman, linux-kernel, Shannon Nelson, Dan Williams,
kernel, linux-arm-kernel
On Saturday 24 November 2007, Haavard Skinnemoen wrote:
> >
> > Why is this needed and is it perhaps something that can be moved to
> > the MMC core?
>
> We used to have lots of problems with overruns and underruns and those
> parameters were useful to limit the transfer rate. Now that the RDPROOF
> and WRPROOF bits seem to have taken care of these problems for good, I
> guess we can remove this parameter.
Not all silicon *has* those bits though, right? Like at91rm9200.
^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [RFC 4/4] Atmel MCI: Driver for Atmel on-chip MMC controllers
2007-11-24 18:48 ` David Brownell
@ 2007-11-24 19:24 ` Haavard Skinnemoen
0 siblings, 0 replies; 11+ messages in thread
From: Haavard Skinnemoen @ 2007-11-24 19:24 UTC (permalink / raw)
To: David Brownell
Cc: Pierre Ossman, linux-kernel, Shannon Nelson, Dan Williams,
kernel, linux-arm-kernel
On Sat, 24 Nov 2007 10:48:39 -0800
David Brownell <david-b@pacbell.net> wrote:
> On Saturday 24 November 2007, Haavard Skinnemoen wrote:
> > >
> > > Why is this needed and is it perhaps something that can be moved
> > > to the MMC core?
> >
> > We used to have lots of problems with overruns and underruns and
> > those parameters were useful to limit the transfer rate. Now that
> > the RDPROOF and WRPROOF bits seem to have taken care of these
> > problems for good, I guess we can remove this parameter.
>
> Not all silicon *has* those bits though, right? Like at91rm9200.
Right. The at91rm9200 doesn't have them, and I believe one of the
at91sam926x chips (at91sam9261?) doesn't have them. So if we're going to
merge this driver with at91_mci, I suppose it makes sense to keep this
parameter.
Haavard
^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [RFC 1/4] dmaengine: Add slave DMA interface
2007-11-23 12:20 ` [RFC 1/4] dmaengine: Add slave DMA interface Haavard Skinnemoen
2007-11-23 12:20 ` [RFC 2/4] dmaengine: Make DMA Engine menu visible for AVR32 users Haavard Skinnemoen
@ 2007-12-03 19:20 ` Dan Williams
2007-12-05 15:53 ` Haavard Skinnemoen
1 sibling, 1 reply; 11+ messages in thread
From: Dan Williams @ 2007-12-03 19:20 UTC (permalink / raw)
To: Haavard Skinnemoen
Cc: linux-kernel, Shannon Nelson, David Brownell, kernel, linux-arm-kernel
Hi Haavard,
Some (delayed) comments.
On Nov 23, 2007 5:20 AM, Haavard Skinnemoen <hskinnemoen@atmel.com> wrote:
> Add a new struct dma_slave_descriptor which extends the standard
> dma_async_tx_descriptor with a few members that are needed for doing
> DMA from/to peripherals with hardware handshaking (aka slave DMA.)
>
> Add new operations to struct dma_device for creating such descriptors,
> for setting up the controller to do slave DMA for a given device, and
> for terminating all pending transfers. The latter is needed because
> there may be errors outside the scope of the DMA Engine framework that
> requires DMA operations to be terminated prematurely.
>
> Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
> ---
> drivers/dma/dmaengine.c | 6 +++++
> include/linux/dmaengine.h | 55 ++++++++++++++++++++++++++++++++++++++++++++-
> 2 files changed, 60 insertions(+), 1 deletions(-)
>
> diff --git a/drivers/dma/dmaengine.c b/drivers/dma/dmaengine.c
> index ec7e871..3d17918 100644
> --- a/drivers/dma/dmaengine.c
> +++ b/drivers/dma/dmaengine.c
> @@ -362,6 +362,12 @@ int dma_async_device_register(struct dma_device *device)
> !device->device_prep_dma_memset);
> BUG_ON(dma_has_cap(DMA_ZERO_SUM, device->cap_mask) &&
> !device->device_prep_dma_interrupt);
> + BUG_ON(dma_has_cap(DMA_SLAVE, device->cap_mask) &&
> + !device->device_set_slave);
> + BUG_ON(dma_has_cap(DMA_SLAVE, device->cap_mask) &&
> + !device->device_prep_slave);
> + BUG_ON(dma_has_cap(DMA_SLAVE, device->cap_mask) &&
> + !device->device_terminate_all);
>
> BUG_ON(!device->device_alloc_chan_resources);
> BUG_ON(!device->device_free_chan_resources);
> diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h
> index 55c9a69..e81189f 100644
> --- a/include/linux/dmaengine.h
> +++ b/include/linux/dmaengine.h
A few questions:
The one change that seems to be missing, at least in my mind, is
extending struct dma_client to include details about the slave device.
Whereas it is assumed that a 'dmaengine' can access kernel memory,
certain device memory regions may be out of bounds for a given
channel.
> @@ -89,10 +89,33 @@ enum dma_transaction_type {
> DMA_MEMSET,
> DMA_MEMCPY_CRC32C,
> DMA_INTERRUPT,
> + DMA_SLAVE,
> };
>
> /* last transaction type for creation of the capabilities mask */
> -#define DMA_TX_TYPE_END (DMA_INTERRUPT + 1)
> +#define DMA_TX_TYPE_END (DMA_SLAVE + 1)
> +
> +/**
> + * enum dma_slave_direction - direction of a DMA slave transfer
> + * @DMA_SLAVE_TO_MEMORY: Transfer data from peripheral to memory
> + * @DMA_SLAVE_FROM_MEMORY: Transfer data from memory to peripheral
> + */
> +enum dma_slave_direction {
> + DMA_SLAVE_TO_MEMORY,
> + DMA_SLAVE_FROM_MEMORY,
> +};
> +
> +/**
> + * enum dma_slave_width - DMA slave register access width.
> + * @DMA_SLAVE_WIDTH_8BIT: Do 8-bit slave register accesses
> + * @DMA_SLAVE_WIDTH_16BIT: Do 16-bit slave register accesses
> + * @DMA_SLAVE_WIDTH_32BIT: Do 32-bit slave register accesses
> + */
> +enum dma_slave_width {
> + DMA_SLAVE_WIDTH_8BIT,
> + DMA_SLAVE_WIDTH_16BIT,
> + DMA_SLAVE_WIDTH_32BIT,
> +};
>
> /**
> * dma_cap_mask_t - capabilities bitmap modeled after cpumask_t.
> @@ -240,6 +263,25 @@ struct dma_async_tx_descriptor {
> };
>
> /**
> + * struct dma_slave_descriptor - extended DMA descriptor for slave DMA
> + * @async_tx: async transaction descriptor
> + * @slave_set_direction: set the direction of the slave DMA
> + * transaction in the hardware descriptor
> + * @slave_set_width: set the slave register access width in the
> + * hardware descriptor
> + * @client_node: for use by the client, for example when operating on
> + * scatterlists.
> + */
> +struct dma_slave_descriptor {
> + struct dma_async_tx_descriptor txd;
> + void (*slave_set_direction)(struct dma_slave_descriptor *desc,
> + enum dma_slave_direction direction);
I have come to the conclusion that the flexibility provided by
'tx_set_src' and 'tx_set_dest' does not really buy anything and adds
unnecessary indirect branch overhead. I am developing a patch to just
add the parameters to the 'device_prep_dma_*' routines. I assume the
same can be said for 'slave_set_direction' unless you can think of a
reason why it should be separate from 'device_prep_slave'?
> + void (*slave_set_width)(struct dma_slave_descriptor *desc,
> + enum dma_slave_width width);
> + struct list_head client_node;
> +};
'slave_set_width' appears to be something that can be done once at
channel allocation time and not per each operation. It seems
channel-slave associations are exclusive since you only call
'device_set_slave' once and do not expect those values to change. So
perhaps moving this all to dmaengine common code makes sense,
something like:
diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h
index 55c9a69..71d4ac2 100644
--- a/include/linux/dmaengine.h
+++ b/include/linux/dmaengine.h
@@ -114,10 +114,18 @@ struct dma_chan_percpu {
unsigned long bytes_transferred;
};
+struct dma_slave_data {
+ struct device *slave;
+ dma_addr_t tx_reg;
+ dma_addr_t rx_reg;
+ enum dma_slave_width width;
+};
+
/**
* struct dma_chan - devices supply DMA channels, clients use them
* @device: ptr to the dma device who supplies this channel, always !%NULL
* @cookie: last cookie value returned to client
+ * @slave_data: data for preparing slave transfers
* @chan_id: channel ID for sysfs
* @class_dev: class device for sysfs
* @refcount: kref, used in "bigref" slow-mode
@@ -129,6 +137,7 @@ struct dma_chan_percpu {
struct dma_chan {
struct dma_device *device;
dma_cookie_t cookie;
+ struct dma_slave_data slave_data;
/* sysfs */
int chan_id;
@@ -193,6 +202,7 @@ typedef enum dma_state_client
(*dma_event_callback) (struct dma_client *client,
struct dma_client {
dma_event_callback event_callback;
dma_cap_mask_t cap_mask;
+ struct device *slave;
struct list_head global_node;
};
If dma_client.slave is non-NULL the client is requesting a channel
with the ability to talk to the given device. If
dma_chan.slave_data.slave is non-NULL this channel has been
exclusively claimed by the given device.
> +
> +/**
> * struct dma_device - info on the entity supplying DMA services
> * @chancnt: how many DMA channels are supported
> * @channels: the list of struct dma_chan
> @@ -258,6 +300,10 @@ struct dma_async_tx_descriptor {
> * @device_prep_dma_zero_sum: prepares a zero_sum operation
> * @device_prep_dma_memset: prepares a memset operation
> * @device_prep_dma_interrupt: prepares an end of chain interrupt operation
> + * @device_set_slave: set up a channel to do slave DMA for a given
> + * peripheral
> + * @device_prep_slave: prepares a slave dma operation
> + * @device_terminate_all: terminate all pending operations
> * @device_dependency_added: async_tx notifies the channel about new deps
> * @device_issue_pending: push pending transactions to hardware
> */
> @@ -291,6 +337,13 @@ struct dma_device {
> struct dma_async_tx_descriptor *(*device_prep_dma_interrupt)(
> struct dma_chan *chan);
>
> + void (*device_set_slave)(struct dma_chan *chan,
> + dma_addr_t rx_reg, unsigned int rx_hs_id,
> + dma_addr_t tx_reg, unsigned int tx_hs_id);
What is the significance of rx_hs_is and tx_hs_id?
> + struct dma_slave_descriptor *(*device_prep_slave)(
> + struct dma_chan *chan, size_t len, int int_en);
> + void (*device_terminate_all)(struct dma_chan *chan);
> +
> void (*device_dependency_added)(struct dma_chan *chan);
> enum dma_status (*device_is_tx_complete)(struct dma_chan *chan,
> dma_cookie_t cookie, dma_cookie_t *last,
> --
Regards,
Dan
^ permalink raw reply related [flat|nested] 11+ messages in thread
* Re: [RFC 1/4] dmaengine: Add slave DMA interface
2007-12-03 19:20 ` [RFC 1/4] dmaengine: Add slave DMA interface Dan Williams
@ 2007-12-05 15:53 ` Haavard Skinnemoen
0 siblings, 0 replies; 11+ messages in thread
From: Haavard Skinnemoen @ 2007-12-05 15:53 UTC (permalink / raw)
To: Dan Williams
Cc: linux-kernel, Shannon Nelson, David Brownell, kernel, linux-arm-kernel
On Mon, 3 Dec 2007 12:20:15 -0700
"Dan Williams" <dan.j.williams@intel.com> wrote:
> Hi Haavard,
>
> Some (delayed) comments.
Thanks for the feedback.
> A few questions:
> The one change that seems to be missing, at least in my mind, is
> extending struct dma_client to include details about the slave device.
> Whereas it is assumed that a 'dmaengine' can access kernel memory,
> certain device memory regions may be out of bounds for a given
> channel.
Hmm. You mean that some channels may not be able to access the slave's
data registers? dma_set_slave() could check this, but I guess it's too
late by then. We should probably add the slave's data register addresses to
the dma_client struct so that the dma core can verify them against the
channel's dma mask when assigning channels to clients.
I suppose we should add other slave-specific data to the dma_client as
well while we're at it, like handshake interface IDs.
> > +struct dma_slave_descriptor {
> > + struct dma_async_tx_descriptor txd;
> > + void (*slave_set_direction)(struct dma_slave_descriptor *desc,
> > + enum dma_slave_direction direction);
>
> I have come to the conclusion that the flexibility provided by
> 'tx_set_src' and 'tx_set_dest' does not really buy anything and adds
> unnecessary indirect branch overhead. I am developing a patch to just
> add the parameters to the 'device_prep_dma_*' routines. I assume the
> same can be said for 'slave_set_direction' unless you can think of a
> reason why it should be separate from 'device_prep_slave'?
I thought that these ops might be useful if the client wants to re-use
the descriptors for multiple transactions. But then you would probably
need a "set_length" hook in the descriptor as well.
> > + void (*slave_set_width)(struct dma_slave_descriptor *desc,
> > + enum dma_slave_width width);
> > + struct list_head client_node;
> > +};
>
> 'slave_set_width' appears to be something that can be done once at
> channel allocation time and not per each operation. It seems
> channel-slave associations are exclusive since you only call
> 'device_set_slave' once and do not expect those values to change. So
> perhaps moving this all to dmaengine common code makes sense,
> something like:
The slave may support different transfer widths. For example, the MMC
driver posted in this thread may need set the controller in "byte mode"
in order to support transfer lengths that are not a multiple of 4
bytes. This means that the DMA transfer width must change as well.
> diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h
> index 55c9a69..71d4ac2 100644
> --- a/include/linux/dmaengine.h
> +++ b/include/linux/dmaengine.h
> @@ -114,10 +114,18 @@ struct dma_chan_percpu {
> unsigned long bytes_transferred;
> };
>
> +struct dma_slave_data {
> + struct device *slave;
> + dma_addr_t tx_reg;
> + dma_addr_t rx_reg;
> + enum dma_slave_width width;
> +};
Yes, we probably need a struct like this. But I don't think we can
assume that the width is fixed for a given slave, and I'm not entirely
sure why we need a struct device here. The dma_mask of the slave is
irrelevant since it can't access any memory on its own.
> /**
> * struct dma_chan - devices supply DMA channels, clients use them
> * @device: ptr to the dma device who supplies this channel, always !%NULL
> * @cookie: last cookie value returned to client
> + * @slave_data: data for preparing slave transfers
> * @chan_id: channel ID for sysfs
> * @class_dev: class device for sysfs
> * @refcount: kref, used in "bigref" slow-mode
> @@ -129,6 +137,7 @@ struct dma_chan_percpu {
> struct dma_chan {
> struct dma_device *device;
> dma_cookie_t cookie;
> + struct dma_slave_data slave_data;
>
> /* sysfs */
> int chan_id;
> @@ -193,6 +202,7 @@ typedef enum dma_state_client
> (*dma_event_callback) (struct dma_client *client,
> struct dma_client {
> dma_event_callback event_callback;
> dma_cap_mask_t cap_mask;
> + struct device *slave;
> struct list_head global_node;
> };
>
> If dma_client.slave is non-NULL the client is requesting a channel
> with the ability to talk to the given device. If
> dma_chan.slave_data.slave is non-NULL this channel has been
> exclusively claimed by the given device.
Or perhaps make dma_chan.slave_data a pointer to struct dma_slave_data
and add a similar pointer to dma_client (or add a separate function for
registering "slave clients".) I don't see how the DMA engine core can
figure out the rest of the data in struct dma_slave_data from a struct
device.
> > +
> > +/**
> > * struct dma_device - info on the entity supplying DMA services
> > * @chancnt: how many DMA channels are supported
> > * @channels: the list of struct dma_chan
> > @@ -258,6 +300,10 @@ struct dma_async_tx_descriptor {
> > * @device_prep_dma_zero_sum: prepares a zero_sum operation
> > * @device_prep_dma_memset: prepares a memset operation
> > * @device_prep_dma_interrupt: prepares an end of chain interrupt operation
> > + * @device_set_slave: set up a channel to do slave DMA for a given
> > + * peripheral
> > + * @device_prep_slave: prepares a slave dma operation
> > + * @device_terminate_all: terminate all pending operations
> > * @device_dependency_added: async_tx notifies the channel about new deps
> > * @device_issue_pending: push pending transactions to hardware
> > */
> > @@ -291,6 +337,13 @@ struct dma_device {
> > struct dma_async_tx_descriptor *(*device_prep_dma_interrupt)(
> > struct dma_chan *chan);
> >
> > + void (*device_set_slave)(struct dma_chan *chan,
> > + dma_addr_t rx_reg, unsigned int rx_hs_id,
> > + dma_addr_t tx_reg, unsigned int tx_hs_id);
>
> What is the significance of rx_hs_is and tx_hs_id?
They identify the peripheral handshaking interfaces associated with the
slave. The slave peripheral uses these to request a transfer from the
DMA controller, so the DMA controller needs to know which interface it
should respond to for a given channel.
I guess this hook can go away if we provide the information at channel
allocation time instead.
Haavard
^ permalink raw reply [flat|nested] 11+ messages in thread
end of thread, other threads:[~2007-12-05 15:54 UTC | newest]
Thread overview: 11+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2007-11-23 12:20 [RFC 0/4] dmaengine: Slave DMA interface and example users Haavard Skinnemoen
2007-11-23 12:20 ` [RFC 1/4] dmaengine: Add slave DMA interface Haavard Skinnemoen
2007-11-23 12:20 ` [RFC 2/4] dmaengine: Make DMA Engine menu visible for AVR32 users Haavard Skinnemoen
2007-11-23 12:20 ` [RFC 3/4] dmaengine: Driver for the Synopsys DesignWare DMA controller Haavard Skinnemoen
2007-11-23 12:20 ` [RFC 4/4] Atmel MCI: Driver for Atmel on-chip MMC controllers Haavard Skinnemoen
2007-11-24 17:00 ` Pierre Ossman
2007-11-24 18:16 ` Haavard Skinnemoen
2007-11-24 18:48 ` David Brownell
2007-11-24 19:24 ` Haavard Skinnemoen
2007-12-03 19:20 ` [RFC 1/4] dmaengine: Add slave DMA interface Dan Williams
2007-12-05 15:53 ` Haavard Skinnemoen
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