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authorVinod Koul <vinod.koul@intel.com>2015-06-25 09:21:58 +0530
committerVinod Koul <vinod.koul@intel.com>2015-06-25 09:21:58 +0530
commitf2704052cb42aabfa19b3f897cbceb70e2e63c45 (patch)
tree441522897d4b6dcc2d5197d7711280214326f190
parent4fb9c15b4f2371b8640c411ceff2c100857aee2c (diff)
parentc91134d9194478144ba579ca6efeddf628055650 (diff)
downloadop-kernel-dev-f2704052cb42aabfa19b3f897cbceb70e2e63c45.zip
op-kernel-dev-f2704052cb42aabfa19b3f897cbceb70e2e63c45.tar.gz
Merge branch 'topic/pxa' into for-linus
-rw-r--r--Documentation/dmaengine/pxa_dma.txt153
-rw-r--r--MAINTAINERS1
-rw-r--r--drivers/dma/Kconfig11
-rw-r--r--drivers/dma/Makefile1
-rw-r--r--drivers/dma/pxa_dma.c1467
-rw-r--r--include/linux/dma/pxa-dma.h27
6 files changed, 1660 insertions, 0 deletions
diff --git a/Documentation/dmaengine/pxa_dma.txt b/Documentation/dmaengine/pxa_dma.txt
new file mode 100644
index 0000000..413ef9c
--- /dev/null
+++ b/Documentation/dmaengine/pxa_dma.txt
@@ -0,0 +1,153 @@
+PXA/MMP - DMA Slave controller
+==============================
+
+Constraints
+-----------
+ a) Transfers hot queuing
+ A driver submitting a transfer and issuing it should be granted the transfer
+ is queued even on a running DMA channel.
+ This implies that the queuing doesn't wait for the previous transfer end,
+ and that the descriptor chaining is not only done in the irq/tasklet code
+ triggered by the end of the transfer.
+ A transfer which is submitted and issued on a phy doesn't wait for a phy to
+ stop and restart, but is submitted on a "running channel". The other
+ drivers, especially mmp_pdma waited for the phy to stop before relaunching
+ a new transfer.
+
+ b) All transfers having asked for confirmation should be signaled
+ Any issued transfer with DMA_PREP_INTERRUPT should trigger a callback call.
+ This implies that even if an irq/tasklet is triggered by end of tx1, but
+ at the time of irq/dma tx2 is already finished, tx1->complete() and
+ tx2->complete() should be called.
+
+ c) Channel running state
+ A driver should be able to query if a channel is running or not. For the
+ multimedia case, such as video capture, if a transfer is submitted and then
+ a check of the DMA channel reports a "stopped channel", the transfer should
+ not be issued until the next "start of frame interrupt", hence the need to
+ know if a channel is in running or stopped state.
+
+ d) Bandwidth guarantee
+ The PXA architecture has 4 levels of DMAs priorities : high, normal, low.
+ The high prorities get twice as much bandwidth as the normal, which get twice
+ as much as the low priorities.
+ A driver should be able to request a priority, especially the real-time
+ ones such as pxa_camera with (big) throughputs.
+
+Design
+------
+ a) Virtual channels
+ Same concept as in sa11x0 driver, ie. a driver was assigned a "virtual
+ channel" linked to the requestor line, and the physical DMA channel is
+ assigned on the fly when the transfer is issued.
+
+ b) Transfer anatomy for a scatter-gather transfer
+ +------------+-----+---------------+----------------+-----------------+
+ | desc-sg[0] | ... | desc-sg[last] | status updater | finisher/linker |
+ +------------+-----+---------------+----------------+-----------------+
+
+ This structure is pointed by dma->sg_cpu.
+ The descriptors are used as follows :
+ - desc-sg[i]: i-th descriptor, transferring the i-th sg
+ element to the video buffer scatter gather
+ - status updater
+ Transfers a single u32 to a well known dma coherent memory to leave
+ a trace that this transfer is done. The "well known" is unique per
+ physical channel, meaning that a read of this value will tell which
+ is the last finished transfer at that point in time.
+ - finisher: has ddadr=DADDR_STOP, dcmd=ENDIRQEN
+ - linker: has ddadr= desc-sg[0] of next transfer, dcmd=0
+
+ c) Transfers hot-chaining
+ Suppose the running chain is :
+ Buffer 1 Buffer 2
+ +---------+----+---+ +----+----+----+---+
+ | d0 | .. | dN | l | | d0 | .. | dN | f |
+ +---------+----+-|-+ ^----+----+----+---+
+ | |
+ +----+
+
+ After a call to dmaengine_submit(b3), the chain will look like :
+ Buffer 1 Buffer 2 Buffer 3
+ +---------+----+---+ +----+----+----+---+ +----+----+----+---+
+ | d0 | .. | dN | l | | d0 | .. | dN | l | | d0 | .. | dN | f |
+ +---------+----+-|-+ ^----+----+----+-|-+ ^----+----+----+---+
+ | | | |
+ +----+ +----+
+ new_link
+
+ If while new_link was created the DMA channel stopped, it is _not_
+ restarted. Hot-chaining doesn't break the assumption that
+ dma_async_issue_pending() is to be used to ensure the transfer is actually started.
+
+ One exception to this rule :
+ - if Buffer1 and Buffer2 had all their addresses 8 bytes aligned
+ - and if Buffer3 has at least one address not 4 bytes aligned
+ - then hot-chaining cannot happen, as the channel must be stopped, the
+ "align bit" must be set, and the channel restarted As a consequence,
+ such a transfer tx_submit() will be queued on the submitted queue, and
+ this specific case if the DMA is already running in aligned mode.
+
+ d) Transfers completion updater
+ Each time a transfer is completed on a channel, an interrupt might be
+ generated or not, up to the client's request. But in each case, the last
+ descriptor of a transfer, the "status updater", will write the latest
+ transfer being completed into the physical channel's completion mark.
+
+ This will speed up residue calculation, for large transfers such as video
+ buffers which hold around 6k descriptors or more. This also allows without
+ any lock to find out what is the latest completed transfer in a running
+ DMA chain.
+
+ e) Transfers completion, irq and tasklet
+ When a transfer flagged as "DMA_PREP_INTERRUPT" is finished, the dma irq
+ is raised. Upon this interrupt, a tasklet is scheduled for the physical
+ channel.
+ The tasklet is responsible for :
+ - reading the physical channel last updater mark
+ - calling all the transfer callbacks of finished transfers, based on
+ that mark, and each transfer flags.
+ If a transfer is completed while this handling is done, a dma irq will
+ be raised, and the tasklet will be scheduled once again, having a new
+ updater mark.
+
+ f) Residue
+ Residue granularity will be descriptor based. The issued but not completed
+ transfers will be scanned for all of their descriptors against the
+ currently running descriptor.
+
+ g) Most complicated case of driver's tx queues
+ The most tricky situation is when :
+ - there are not "acked" transfers (tx0)
+ - a driver submitted an aligned tx1, not chained
+ - a driver submitted an aligned tx2 => tx2 is cold chained to tx1
+ - a driver issued tx1+tx2 => channel is running in aligned mode
+ - a driver submitted an aligned tx3 => tx3 is hot-chained
+ - a driver submitted an unaligned tx4 => tx4 is put in submitted queue,
+ not chained
+ - a driver issued tx4 => tx4 is put in issued queue, not chained
+ - a driver submitted an aligned tx5 => tx5 is put in submitted queue, not
+ chained
+ - a driver submitted an aligned tx6 => tx6 is put in submitted queue,
+ cold chained to tx5
+
+ This translates into (after tx4 is issued) :
+ - issued queue
+ +-----+ +-----+ +-----+ +-----+
+ | tx1 | | tx2 | | tx3 | | tx4 |
+ +---|-+ ^---|-+ ^-----+ +-----+
+ | | | |
+ +---+ +---+
+ - submitted queue
+ +-----+ +-----+
+ | tx5 | | tx6 |
+ +---|-+ ^-----+
+ | |
+ +---+
+ - completed queue : empty
+ - allocated queue : tx0
+
+ It should be noted that after tx3 is completed, the channel is stopped, and
+ restarted in "unaligned mode" to handle tx4.
+
+Author: Robert Jarzmik <robert.jarzmik@free.fr>
diff --git a/MAINTAINERS b/MAINTAINERS
index 781e099..238ea99 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -7937,6 +7937,7 @@ T: git git://github.com/hzhuang1/linux.git
T: git git://github.com/rjarzmik/linux.git
S: Maintained
F: arch/arm/mach-pxa/
+F: drivers/dma/pxa*
F: drivers/pcmcia/pxa2xx*
F: drivers/spi/spi-pxa2xx*
F: drivers/usb/gadget/udc/pxa2*
diff --git a/drivers/dma/Kconfig b/drivers/dma/Kconfig
index 0205ade..88d474b 100644
--- a/drivers/dma/Kconfig
+++ b/drivers/dma/Kconfig
@@ -162,6 +162,17 @@ config MX3_IPU_IRQS
To avoid bloating the irq_desc[] array we allocate a sufficient
number of IRQ slots and map them dynamically to specific sources.
+config PXA_DMA
+ bool "PXA DMA support"
+ depends on (ARCH_MMP || ARCH_PXA)
+ select DMA_ENGINE
+ select DMA_VIRTUAL_CHANNELS
+ help
+ Support the DMA engine for PXA. It is also compatible with MMP PDMA
+ platform. The internal DMA IP of all PXA variants is supported, with
+ 16 to 32 channels for peripheral to memory or memory to memory
+ transfers.
+
config TXX9_DMAC
tristate "Toshiba TXx9 SoC DMA support"
depends on MACH_TX49XX || MACH_TX39XX
diff --git a/drivers/dma/Makefile b/drivers/dma/Makefile
index 5359195..6a4d6f2 100644
--- a/drivers/dma/Makefile
+++ b/drivers/dma/Makefile
@@ -25,6 +25,7 @@ obj-$(CONFIG_AMCC_PPC440SPE_ADMA) += ppc4xx/
obj-$(CONFIG_IMX_SDMA) += imx-sdma.o
obj-$(CONFIG_IMX_DMA) += imx-dma.o
obj-$(CONFIG_MXS_DMA) += mxs-dma.o
+obj-$(CONFIG_PXA_DMA) += pxa_dma.o
obj-$(CONFIG_TIMB_DMA) += timb_dma.o
obj-$(CONFIG_SIRF_DMA) += sirf-dma.o
obj-$(CONFIG_TI_EDMA) += edma.o
diff --git a/drivers/dma/pxa_dma.c b/drivers/dma/pxa_dma.c
new file mode 100644
index 0000000..ddcbbf5
--- /dev/null
+++ b/drivers/dma/pxa_dma.c
@@ -0,0 +1,1467 @@
+/*
+ * Copyright 2015 Robert Jarzmik <robert.jarzmik@free.fr>
+ *
+ * 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/err.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/types.h>
+#include <linux/interrupt.h>
+#include <linux/dma-mapping.h>
+#include <linux/slab.h>
+#include <linux/dmaengine.h>
+#include <linux/platform_device.h>
+#include <linux/device.h>
+#include <linux/platform_data/mmp_dma.h>
+#include <linux/dmapool.h>
+#include <linux/of_device.h>
+#include <linux/of_dma.h>
+#include <linux/of.h>
+#include <linux/dma/pxa-dma.h>
+
+#include "dmaengine.h"
+#include "virt-dma.h"
+
+#define DCSR(n) (0x0000 + ((n) << 2))
+#define DALGN(n) 0x00a0
+#define DINT 0x00f0
+#define DDADR(n) (0x0200 + ((n) << 4))
+#define DSADR(n) (0x0204 + ((n) << 4))
+#define DTADR(n) (0x0208 + ((n) << 4))
+#define DCMD(n) (0x020c + ((n) << 4))
+
+#define PXA_DCSR_RUN BIT(31) /* Run Bit (read / write) */
+#define PXA_DCSR_NODESC BIT(30) /* No-Descriptor Fetch (read / write) */
+#define PXA_DCSR_STOPIRQEN BIT(29) /* Stop Interrupt Enable (R/W) */
+#define PXA_DCSR_REQPEND BIT(8) /* Request Pending (read-only) */
+#define PXA_DCSR_STOPSTATE BIT(3) /* Stop State (read-only) */
+#define PXA_DCSR_ENDINTR BIT(2) /* End Interrupt (read / write) */
+#define PXA_DCSR_STARTINTR BIT(1) /* Start Interrupt (read / write) */
+#define PXA_DCSR_BUSERR BIT(0) /* Bus Error Interrupt (read / write) */
+
+#define PXA_DCSR_EORIRQEN BIT(28) /* End of Receive IRQ Enable (R/W) */
+#define PXA_DCSR_EORJMPEN BIT(27) /* Jump to next descriptor on EOR */
+#define PXA_DCSR_EORSTOPEN BIT(26) /* STOP on an EOR */
+#define PXA_DCSR_SETCMPST BIT(25) /* Set Descriptor Compare Status */
+#define PXA_DCSR_CLRCMPST BIT(24) /* Clear Descriptor Compare Status */
+#define PXA_DCSR_CMPST BIT(10) /* The Descriptor Compare Status */
+#define PXA_DCSR_EORINTR BIT(9) /* The end of Receive */
+
+#define DRCMR_MAPVLD BIT(7) /* Map Valid (read / write) */
+#define DRCMR_CHLNUM 0x1f /* mask for Channel Number (read / write) */
+
+#define DDADR_DESCADDR 0xfffffff0 /* Address of next descriptor (mask) */
+#define DDADR_STOP BIT(0) /* Stop (read / write) */
+
+#define PXA_DCMD_INCSRCADDR BIT(31) /* Source Address Increment Setting. */
+#define PXA_DCMD_INCTRGADDR BIT(30) /* Target Address Increment Setting. */
+#define PXA_DCMD_FLOWSRC BIT(29) /* Flow Control by the source. */
+#define PXA_DCMD_FLOWTRG BIT(28) /* Flow Control by the target. */
+#define PXA_DCMD_STARTIRQEN BIT(22) /* Start Interrupt Enable */
+#define PXA_DCMD_ENDIRQEN BIT(21) /* End Interrupt Enable */
+#define PXA_DCMD_ENDIAN BIT(18) /* Device Endian-ness. */
+#define PXA_DCMD_BURST8 (1 << 16) /* 8 byte burst */
+#define PXA_DCMD_BURST16 (2 << 16) /* 16 byte burst */
+#define PXA_DCMD_BURST32 (3 << 16) /* 32 byte burst */
+#define PXA_DCMD_WIDTH1 (1 << 14) /* 1 byte width */
+#define PXA_DCMD_WIDTH2 (2 << 14) /* 2 byte width (HalfWord) */
+#define PXA_DCMD_WIDTH4 (3 << 14) /* 4 byte width (Word) */
+#define PXA_DCMD_LENGTH 0x01fff /* length mask (max = 8K - 1) */
+
+#define PDMA_ALIGNMENT 3
+#define PDMA_MAX_DESC_BYTES (PXA_DCMD_LENGTH & ~((1 << PDMA_ALIGNMENT) - 1))
+
+struct pxad_desc_hw {
+ u32 ddadr; /* Points to the next descriptor + flags */
+ u32 dsadr; /* DSADR value for the current transfer */
+ u32 dtadr; /* DTADR value for the current transfer */
+ u32 dcmd; /* DCMD value for the current transfer */
+} __aligned(16);
+
+struct pxad_desc_sw {
+ struct virt_dma_desc vd; /* Virtual descriptor */
+ int nb_desc; /* Number of hw. descriptors */
+ size_t len; /* Number of bytes xfered */
+ dma_addr_t first; /* First descriptor's addr */
+
+ /* At least one descriptor has an src/dst address not multiple of 8 */
+ bool misaligned;
+ bool cyclic;
+ struct dma_pool *desc_pool; /* Channel's used allocator */
+
+ struct pxad_desc_hw *hw_desc[]; /* DMA coherent descriptors */
+};
+
+struct pxad_phy {
+ int idx;
+ void __iomem *base;
+ struct pxad_chan *vchan;
+};
+
+struct pxad_chan {
+ struct virt_dma_chan vc; /* Virtual channel */
+ u32 drcmr; /* Requestor of the channel */
+ enum pxad_chan_prio prio; /* Required priority of phy */
+ /*
+ * At least one desc_sw in submitted or issued transfers on this channel
+ * has one address such as: addr % 8 != 0. This implies the DALGN
+ * setting on the phy.
+ */
+ bool misaligned;
+ struct dma_slave_config cfg; /* Runtime config */
+
+ /* protected by vc->lock */
+ struct pxad_phy *phy;
+ struct dma_pool *desc_pool; /* Descriptors pool */
+};
+
+struct pxad_device {
+ struct dma_device slave;
+ int nr_chans;
+ void __iomem *base;
+ struct pxad_phy *phys;
+ spinlock_t phy_lock; /* Phy association */
+#ifdef CONFIG_DEBUG_FS
+ struct dentry *dbgfs_root;
+ struct dentry *dbgfs_state;
+ struct dentry **dbgfs_chan;
+#endif
+};
+
+#define tx_to_pxad_desc(tx) \
+ container_of(tx, struct pxad_desc_sw, async_tx)
+#define to_pxad_chan(dchan) \
+ container_of(dchan, struct pxad_chan, vc.chan)
+#define to_pxad_dev(dmadev) \
+ container_of(dmadev, struct pxad_device, slave)
+#define to_pxad_sw_desc(_vd) \
+ container_of((_vd), struct pxad_desc_sw, vd)
+
+#define _phy_readl_relaxed(phy, _reg) \
+ readl_relaxed((phy)->base + _reg((phy)->idx))
+#define phy_readl_relaxed(phy, _reg) \
+ ({ \
+ u32 _v; \
+ _v = readl_relaxed((phy)->base + _reg((phy)->idx)); \
+ dev_vdbg(&phy->vchan->vc.chan.dev->device, \
+ "%s(): readl(%s): 0x%08x\n", __func__, #_reg, \
+ _v); \
+ _v; \
+ })
+#define phy_writel(phy, val, _reg) \
+ do { \
+ writel((val), (phy)->base + _reg((phy)->idx)); \
+ dev_vdbg(&phy->vchan->vc.chan.dev->device, \
+ "%s(): writel(0x%08x, %s)\n", \
+ __func__, (u32)(val), #_reg); \
+ } while (0)
+#define phy_writel_relaxed(phy, val, _reg) \
+ do { \
+ writel_relaxed((val), (phy)->base + _reg((phy)->idx)); \
+ dev_vdbg(&phy->vchan->vc.chan.dev->device, \
+ "%s(): writel_relaxed(0x%08x, %s)\n", \
+ __func__, (u32)(val), #_reg); \
+ } while (0)
+
+static unsigned int pxad_drcmr(unsigned int line)
+{
+ if (line < 64)
+ return 0x100 + line * 4;
+ return 0x1000 + line * 4;
+}
+
+/*
+ * Debug fs
+ */
+#ifdef CONFIG_DEBUG_FS
+#include <linux/debugfs.h>
+#include <linux/uaccess.h>
+#include <linux/seq_file.h>
+
+static int dbg_show_requester_chan(struct seq_file *s, void *p)
+{
+ int pos = 0;
+ struct pxad_phy *phy = s->private;
+ int i;
+ u32 drcmr;
+
+ pos += seq_printf(s, "DMA channel %d requester :\n", phy->idx);
+ for (i = 0; i < 70; i++) {
+ drcmr = readl_relaxed(phy->base + pxad_drcmr(i));
+ if ((drcmr & DRCMR_CHLNUM) == phy->idx)
+ pos += seq_printf(s, "\tRequester %d (MAPVLD=%d)\n", i,
+ !!(drcmr & DRCMR_MAPVLD));
+ }
+ return pos;
+}
+
+static inline int dbg_burst_from_dcmd(u32 dcmd)
+{
+ int burst = (dcmd >> 16) & 0x3;
+
+ return burst ? 4 << burst : 0;
+}
+
+static int is_phys_valid(unsigned long addr)
+{
+ return pfn_valid(__phys_to_pfn(addr));
+}
+
+#define PXA_DCSR_STR(flag) (dcsr & PXA_DCSR_##flag ? #flag" " : "")
+#define PXA_DCMD_STR(flag) (dcmd & PXA_DCMD_##flag ? #flag" " : "")
+
+static int dbg_show_descriptors(struct seq_file *s, void *p)
+{
+ struct pxad_phy *phy = s->private;
+ int i, max_show = 20, burst, width;
+ u32 dcmd;
+ unsigned long phys_desc, ddadr;
+ struct pxad_desc_hw *desc;
+
+ phys_desc = ddadr = _phy_readl_relaxed(phy, DDADR);
+
+ seq_printf(s, "DMA channel %d descriptors :\n", phy->idx);
+ seq_printf(s, "[%03d] First descriptor unknown\n", 0);
+ for (i = 1; i < max_show && is_phys_valid(phys_desc); i++) {
+ desc = phys_to_virt(phys_desc);
+ dcmd = desc->dcmd;
+ burst = dbg_burst_from_dcmd(dcmd);
+ width = (1 << ((dcmd >> 14) & 0x3)) >> 1;
+
+ seq_printf(s, "[%03d] Desc at %08lx(virt %p)\n",
+ i, phys_desc, desc);
+ seq_printf(s, "\tDDADR = %08x\n", desc->ddadr);
+ seq_printf(s, "\tDSADR = %08x\n", desc->dsadr);
+ seq_printf(s, "\tDTADR = %08x\n", desc->dtadr);
+ seq_printf(s, "\tDCMD = %08x (%s%s%s%s%s%s%sburst=%d width=%d len=%d)\n",
+ dcmd,
+ PXA_DCMD_STR(INCSRCADDR), PXA_DCMD_STR(INCTRGADDR),
+ PXA_DCMD_STR(FLOWSRC), PXA_DCMD_STR(FLOWTRG),
+ PXA_DCMD_STR(STARTIRQEN), PXA_DCMD_STR(ENDIRQEN),
+ PXA_DCMD_STR(ENDIAN), burst, width,
+ dcmd & PXA_DCMD_LENGTH);
+ phys_desc = desc->ddadr;
+ }
+ if (i == max_show)
+ seq_printf(s, "[%03d] Desc at %08lx ... max display reached\n",
+ i, phys_desc);
+ else
+ seq_printf(s, "[%03d] Desc at %08lx is %s\n",
+ i, phys_desc, phys_desc == DDADR_STOP ?
+ "DDADR_STOP" : "invalid");
+
+ return 0;
+}
+
+static int dbg_show_chan_state(struct seq_file *s, void *p)
+{
+ struct pxad_phy *phy = s->private;
+ u32 dcsr, dcmd;
+ int burst, width;
+ static const char * const str_prio[] = {
+ "high", "normal", "low", "invalid"
+ };
+
+ dcsr = _phy_readl_relaxed(phy, DCSR);
+ dcmd = _phy_readl_relaxed(phy, DCMD);
+ burst = dbg_burst_from_dcmd(dcmd);
+ width = (1 << ((dcmd >> 14) & 0x3)) >> 1;
+
+ seq_printf(s, "DMA channel %d\n", phy->idx);
+ seq_printf(s, "\tPriority : %s\n",
+ str_prio[(phy->idx & 0xf) / 4]);
+ seq_printf(s, "\tUnaligned transfer bit: %s\n",
+ _phy_readl_relaxed(phy, DALGN) & BIT(phy->idx) ?
+ "yes" : "no");
+ seq_printf(s, "\tDCSR = %08x (%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s)\n",
+ dcsr, PXA_DCSR_STR(RUN), PXA_DCSR_STR(NODESC),
+ PXA_DCSR_STR(STOPIRQEN), PXA_DCSR_STR(EORIRQEN),
+ PXA_DCSR_STR(EORJMPEN), PXA_DCSR_STR(EORSTOPEN),
+ PXA_DCSR_STR(SETCMPST), PXA_DCSR_STR(CLRCMPST),
+ PXA_DCSR_STR(CMPST), PXA_DCSR_STR(EORINTR),
+ PXA_DCSR_STR(REQPEND), PXA_DCSR_STR(STOPSTATE),
+ PXA_DCSR_STR(ENDINTR), PXA_DCSR_STR(STARTINTR),
+ PXA_DCSR_STR(BUSERR));
+
+ seq_printf(s, "\tDCMD = %08x (%s%s%s%s%s%s%sburst=%d width=%d len=%d)\n",
+ dcmd,
+ PXA_DCMD_STR(INCSRCADDR), PXA_DCMD_STR(INCTRGADDR),
+ PXA_DCMD_STR(FLOWSRC), PXA_DCMD_STR(FLOWTRG),
+ PXA_DCMD_STR(STARTIRQEN), PXA_DCMD_STR(ENDIRQEN),
+ PXA_DCMD_STR(ENDIAN), burst, width, dcmd & PXA_DCMD_LENGTH);
+ seq_printf(s, "\tDSADR = %08x\n", _phy_readl_relaxed(phy, DSADR));
+ seq_printf(s, "\tDTADR = %08x\n", _phy_readl_relaxed(phy, DTADR));
+ seq_printf(s, "\tDDADR = %08x\n", _phy_readl_relaxed(phy, DDADR));
+
+ return 0;
+}
+
+static int dbg_show_state(struct seq_file *s, void *p)
+{
+ struct pxad_device *pdev = s->private;
+
+ /* basic device status */
+ seq_puts(s, "DMA engine status\n");
+ seq_printf(s, "\tChannel number: %d\n", pdev->nr_chans);
+
+ return 0;
+}
+
+#define DBGFS_FUNC_DECL(name) \
+static int dbg_open_##name(struct inode *inode, struct file *file) \
+{ \
+ return single_open(file, dbg_show_##name, inode->i_private); \
+} \
+static const struct file_operations dbg_fops_##name = { \
+ .owner = THIS_MODULE, \
+ .open = dbg_open_##name, \
+ .llseek = seq_lseek, \
+ .read = seq_read, \
+ .release = single_release, \
+}
+
+DBGFS_FUNC_DECL(state);
+DBGFS_FUNC_DECL(chan_state);
+DBGFS_FUNC_DECL(descriptors);
+DBGFS_FUNC_DECL(requester_chan);
+
+static struct dentry *pxad_dbg_alloc_chan(struct pxad_device *pdev,
+ int ch, struct dentry *chandir)
+{
+ char chan_name[11];
+ struct dentry *chan, *chan_state = NULL, *chan_descr = NULL;
+ struct dentry *chan_reqs = NULL;
+ void *dt;
+
+ scnprintf(chan_name, sizeof(chan_name), "%d", ch);
+ chan = debugfs_create_dir(chan_name, chandir);
+ dt = (void *)&pdev->phys[ch];
+
+ if (chan)
+ chan_state = debugfs_create_file("state", 0400, chan, dt,
+ &dbg_fops_chan_state);
+ if (chan_state)
+ chan_descr = debugfs_create_file("descriptors", 0400, chan, dt,
+ &dbg_fops_descriptors);
+ if (chan_descr)
+ chan_reqs = debugfs_create_file("requesters", 0400, chan, dt,
+ &dbg_fops_requester_chan);
+ if (!chan_reqs)
+ goto err_state;
+
+ return chan;
+
+err_state:
+ debugfs_remove_recursive(chan);
+ return NULL;
+}
+
+static void pxad_init_debugfs(struct pxad_device *pdev)
+{
+ int i;
+ struct dentry *chandir;
+
+ pdev->dbgfs_root = debugfs_create_dir(dev_name(pdev->slave.dev), NULL);
+ if (IS_ERR(pdev->dbgfs_root) || !pdev->dbgfs_root)
+ goto err_root;
+
+ pdev->dbgfs_state = debugfs_create_file("state", 0400, pdev->dbgfs_root,
+ pdev, &dbg_fops_state);
+ if (!pdev->dbgfs_state)
+ goto err_state;
+
+ pdev->dbgfs_chan =
+ kmalloc_array(pdev->nr_chans, sizeof(*pdev->dbgfs_state),
+ GFP_KERNEL);
+ if (!pdev->dbgfs_chan)
+ goto err_alloc;
+
+ chandir = debugfs_create_dir("channels", pdev->dbgfs_root);
+ if (!chandir)
+ goto err_chandir;
+
+ for (i = 0; i < pdev->nr_chans; i++) {
+ pdev->dbgfs_chan[i] = pxad_dbg_alloc_chan(pdev, i, chandir);
+ if (!pdev->dbgfs_chan[i])
+ goto err_chans;
+ }
+
+ return;
+err_chans:
+err_chandir:
+ kfree(pdev->dbgfs_chan);
+err_alloc:
+err_state:
+ debugfs_remove_recursive(pdev->dbgfs_root);
+err_root:
+ pr_err("pxad: debugfs is not available\n");
+}
+
+static void pxad_cleanup_debugfs(struct pxad_device *pdev)
+{
+ debugfs_remove_recursive(pdev->dbgfs_root);
+}
+#else
+static inline void pxad_init_debugfs(struct pxad_device *pdev) {}
+static inline void pxad_cleanup_debugfs(struct pxad_device *pdev) {}
+#endif
+
+/*
+ * In the transition phase where legacy pxa handling is done at the same time as
+ * mmp_dma, the DMA physical channel split between the 2 DMA providers is done
+ * through legacy_reserved. Legacy code reserves DMA channels by settings
+ * corresponding bits in legacy_reserved.
+ */
+static u32 legacy_reserved;
+static u32 legacy_unavailable;
+
+static struct pxad_phy *lookup_phy(struct pxad_chan *pchan)
+{
+ int prio, i;
+ struct pxad_device *pdev = to_pxad_dev(pchan->vc.chan.device);
+ struct pxad_phy *phy, *found = NULL;
+ unsigned long flags;
+
+ /*
+ * dma channel priorities
+ * ch 0 - 3, 16 - 19 <--> (0)
+ * ch 4 - 7, 20 - 23 <--> (1)
+ * ch 8 - 11, 24 - 27 <--> (2)
+ * ch 12 - 15, 28 - 31 <--> (3)
+ */
+
+ spin_lock_irqsave(&pdev->phy_lock, flags);
+ for (prio = pchan->prio; prio >= PXAD_PRIO_HIGHEST; prio--) {
+ for (i = 0; i < pdev->nr_chans; i++) {
+ if (prio != (i & 0xf) >> 2)
+ continue;
+ if ((i < 32) && (legacy_reserved & BIT(i)))
+ continue;
+ phy = &pdev->phys[i];
+ if (!phy->vchan) {
+ phy->vchan = pchan;
+ found = phy;
+ if (i < 32)
+ legacy_unavailable |= BIT(i);
+ goto out_unlock;
+ }
+ }
+ }
+
+out_unlock:
+ spin_unlock_irqrestore(&pdev->phy_lock, flags);
+ dev_dbg(&pchan->vc.chan.dev->device,
+ "%s(): phy=%p(%d)\n", __func__, found,
+ found ? found->idx : -1);
+
+ return found;
+}
+
+static void pxad_free_phy(struct pxad_chan *chan)
+{
+ struct pxad_device *pdev = to_pxad_dev(chan->vc.chan.device);
+ unsigned long flags;
+ u32 reg;
+ int i;
+
+ dev_dbg(&chan->vc.chan.dev->device,
+ "%s(): freeing\n", __func__);
+ if (!chan->phy)
+ return;
+
+ /* clear the channel mapping in DRCMR */
+ reg = pxad_drcmr(chan->drcmr);
+ writel_relaxed(0, chan->phy->base + reg);
+
+ spin_lock_irqsave(&pdev->phy_lock, flags);
+ for (i = 0; i < 32; i++)
+ if (chan->phy == &pdev->phys[i])
+ legacy_unavailable &= ~BIT(i);
+ chan->phy->vchan = NULL;
+ chan->phy = NULL;
+ spin_unlock_irqrestore(&pdev->phy_lock, flags);
+}
+
+static bool is_chan_running(struct pxad_chan *chan)
+{
+ u32 dcsr;
+ struct pxad_phy *phy = chan->phy;
+
+ if (!phy)
+ return false;
+ dcsr = phy_readl_relaxed(phy, DCSR);
+ return dcsr & PXA_DCSR_RUN;
+}
+
+static bool is_running_chan_misaligned(struct pxad_chan *chan)
+{
+ u32 dalgn;
+
+ BUG_ON(!chan->phy);
+ dalgn = phy_readl_relaxed(chan->phy, DALGN);
+ return dalgn & (BIT(chan->phy->idx));
+}
+
+static void phy_enable(struct pxad_phy *phy, bool misaligned)
+{
+ u32 reg, dalgn;
+
+ if (!phy->vchan)
+ return;
+
+ dev_dbg(&phy->vchan->vc.chan.dev->device,
+ "%s(); phy=%p(%d) misaligned=%d\n", __func__,
+ phy, phy->idx, misaligned);
+
+ reg = pxad_drcmr(phy->vchan->drcmr);
+ writel_relaxed(DRCMR_MAPVLD | phy->idx, phy->base + reg);
+
+ dalgn = phy_readl_relaxed(phy, DALGN);
+ if (misaligned)
+ dalgn |= BIT(phy->idx);
+ else
+ dalgn &= ~BIT(phy->idx);
+ phy_writel_relaxed(phy, dalgn, DALGN);
+
+ phy_writel(phy, PXA_DCSR_STOPIRQEN | PXA_DCSR_ENDINTR |
+ PXA_DCSR_BUSERR | PXA_DCSR_RUN, DCSR);
+}
+
+static void phy_disable(struct pxad_phy *phy)
+{
+ u32 dcsr;
+
+ if (!phy)
+ return;
+
+ dcsr = phy_readl_relaxed(phy, DCSR);
+ dev_dbg(&phy->vchan->vc.chan.dev->device,
+ "%s(): phy=%p(%d)\n", __func__, phy, phy->idx);
+ phy_writel(phy, dcsr & ~PXA_DCSR_RUN & ~PXA_DCSR_STOPIRQEN, DCSR);
+}
+
+static void pxad_launch_chan(struct pxad_chan *chan,
+ struct pxad_desc_sw *desc)
+{
+ dev_dbg(&chan->vc.chan.dev->device,
+ "%s(): desc=%p\n", __func__, desc);
+ if (!chan->phy) {
+ chan->phy = lookup_phy(chan);
+ if (!chan->phy) {
+ dev_dbg(&chan->vc.chan.dev->device,
+ "%s(): no free dma channel\n", __func__);
+ return;
+ }
+ }
+
+ /*
+ * Program the descriptor's address into the DMA controller,
+ * then start the DMA transaction
+ */
+ phy_writel(chan->phy, desc->first, DDADR);
+ phy_enable(chan->phy, chan->misaligned);
+}
+
+static void set_updater_desc(struct pxad_desc_sw *sw_desc,
+ unsigned long flags)
+{
+ struct pxad_desc_hw *updater =
+ sw_desc->hw_desc[sw_desc->nb_desc - 1];
+ dma_addr_t dma = sw_desc->hw_desc[sw_desc->nb_desc - 2]->ddadr;
+
+ updater->ddadr = DDADR_STOP;
+ updater->dsadr = dma;
+ updater->dtadr = dma + 8;
+ updater->dcmd = PXA_DCMD_WIDTH4 | PXA_DCMD_BURST32 |
+ (PXA_DCMD_LENGTH & sizeof(u32));
+ if (flags & DMA_PREP_INTERRUPT)
+ updater->dcmd |= PXA_DCMD_ENDIRQEN;
+}
+
+static bool is_desc_completed(struct virt_dma_desc *vd)
+{
+ struct pxad_desc_sw *sw_desc = to_pxad_sw_desc(vd);
+ struct pxad_desc_hw *updater =
+ sw_desc->hw_desc[sw_desc->nb_desc - 1];
+
+ return updater->dtadr != (updater->dsadr + 8);
+}
+
+static void pxad_desc_chain(struct virt_dma_desc *vd1,
+ struct virt_dma_desc *vd2)
+{
+ struct pxad_desc_sw *desc1 = to_pxad_sw_desc(vd1);
+ struct pxad_desc_sw *desc2 = to_pxad_sw_desc(vd2);
+ dma_addr_t dma_to_chain;
+
+ dma_to_chain = desc2->first;
+ desc1->hw_desc[desc1->nb_desc - 1]->ddadr = dma_to_chain;
+}
+
+static bool pxad_try_hotchain(struct virt_dma_chan *vc,
+ struct virt_dma_desc *vd)
+{
+ struct virt_dma_desc *vd_last_issued = NULL;
+ struct pxad_chan *chan = to_pxad_chan(&vc->chan);
+
+ /*
+ * Attempt to hot chain the tx if the phy is still running. This is
+ * considered successful only if either the channel is still running
+ * after the chaining, or if the chained transfer is completed after
+ * having been hot chained.
+ * A change of alignment is not allowed, and forbids hotchaining.
+ */
+ if (is_chan_running(chan)) {
+ BUG_ON(list_empty(&vc->desc_issued));
+
+ if (!is_running_chan_misaligned(chan) &&
+ to_pxad_sw_desc(vd)->misaligned)
+ return false;
+
+ vd_last_issued = list_entry(vc->desc_issued.prev,
+ struct virt_dma_desc, node);
+ pxad_desc_chain(vd_last_issued, vd);
+ if (is_chan_running(chan) || is_desc_completed(vd_last_issued))
+ return true;
+ }
+
+ return false;
+}
+
+static unsigned int clear_chan_irq(struct pxad_phy *phy)
+{
+ u32 dcsr;
+ u32 dint = readl(phy->base + DINT);
+
+ if (!(dint & BIT(phy->idx)))
+ return PXA_DCSR_RUN;
+
+ /* clear irq */
+ dcsr = phy_readl_relaxed(phy, DCSR);
+ phy_writel(phy, dcsr, DCSR);
+ if ((dcsr & PXA_DCSR_BUSERR) && (phy->vchan))
+ dev_warn(&phy->vchan->vc.chan.dev->device,
+ "%s(chan=%p): PXA_DCSR_BUSERR\n",
+ __func__, &phy->vchan);
+
+ return dcsr & ~PXA_DCSR_RUN;
+}
+
+static irqreturn_t pxad_chan_handler(int irq, void *dev_id)
+{
+ struct pxad_phy *phy = dev_id;
+ struct pxad_chan *chan = phy->vchan;
+ struct virt_dma_desc *vd, *tmp;
+ unsigned int dcsr;
+ unsigned long flags;
+
+ BUG_ON(!chan);
+
+ dcsr = clear_chan_irq(phy);
+ if (dcsr & PXA_DCSR_RUN)
+ return IRQ_NONE;
+
+ spin_lock_irqsave(&chan->vc.lock, flags);
+ list_for_each_entry_safe(vd, tmp, &chan->vc.desc_issued, node) {
+ dev_dbg(&chan->vc.chan.dev->device,
+ "%s(): checking txd %p[%x]: completed=%d\n",
+ __func__, vd, vd->tx.cookie, is_desc_completed(vd));
+ if (is_desc_completed(vd)) {
+ list_del(&vd->node);
+ vchan_cookie_complete(vd);
+ } else {
+ break;
+ }
+ }
+
+ if (dcsr & PXA_DCSR_STOPSTATE) {
+ dev_dbg(&chan->vc.chan.dev->device,
+ "%s(): channel stopped, submitted_empty=%d issued_empty=%d",
+ __func__,
+ list_empty(&chan->vc.desc_submitted),
+ list_empty(&chan->vc.desc_issued));
+ phy_writel_relaxed(phy, dcsr & ~PXA_DCSR_STOPIRQEN, DCSR);
+
+ if (list_empty(&chan->vc.desc_issued)) {
+ chan->misaligned =
+ !list_empty(&chan->vc.desc_submitted);
+ } else {
+ vd = list_first_entry(&chan->vc.desc_issued,
+ struct virt_dma_desc, node);
+ pxad_launch_chan(chan, to_pxad_sw_desc(vd));
+ }
+ }
+ spin_unlock_irqrestore(&chan->vc.lock, flags);
+
+ return IRQ_HANDLED;
+}
+
+static irqreturn_t pxad_int_handler(int irq, void *dev_id)
+{
+ struct pxad_device *pdev = dev_id;
+ struct pxad_phy *phy;
+ u32 dint = readl(pdev->base + DINT);
+ int i, ret = IRQ_NONE;
+
+ while (dint) {
+ i = __ffs(dint);
+ dint &= (dint - 1);
+ phy = &pdev->phys[i];
+ if ((i < 32) && (legacy_reserved & BIT(i)))
+ continue;
+ if (pxad_chan_handler(irq, phy) == IRQ_HANDLED)
+ ret = IRQ_HANDLED;
+ }
+
+ return ret;
+}
+
+static int pxad_alloc_chan_resources(struct dma_chan *dchan)
+{
+ struct pxad_chan *chan = to_pxad_chan(dchan);
+ struct pxad_device *pdev = to_pxad_dev(chan->vc.chan.device);
+
+ if (chan->desc_pool)
+ return 1;
+
+ chan->desc_pool = dma_pool_create(dma_chan_name(dchan),
+ pdev->slave.dev,
+ sizeof(struct pxad_desc_hw),
+ __alignof__(struct pxad_desc_hw),
+ 0);
+ if (!chan->desc_pool) {
+ dev_err(&chan->vc.chan.dev->device,
+ "%s(): unable to allocate descriptor pool\n",
+ __func__);
+ return -ENOMEM;
+ }
+
+ return 1;
+}
+
+static void pxad_free_chan_resources(struct dma_chan *dchan)
+{
+ struct pxad_chan *chan = to_pxad_chan(dchan);
+
+ vchan_free_chan_resources(&chan->vc);
+ dma_pool_destroy(chan->desc_pool);
+ chan->desc_pool = NULL;
+
+}
+
+static void pxad_free_desc(struct virt_dma_desc *vd)
+{
+ int i;
+ dma_addr_t dma;
+ struct pxad_desc_sw *sw_desc = to_pxad_sw_desc(vd);
+
+ BUG_ON(sw_desc->nb_desc == 0);
+ for (i = sw_desc->nb_desc - 1; i >= 0; i--) {
+ if (i > 0)
+ dma = sw_desc->hw_desc[i - 1]->ddadr;
+ else
+ dma = sw_desc->first;
+ dma_pool_free(sw_desc->desc_pool,
+ sw_desc->hw_desc[i], dma);
+ }
+ sw_desc->nb_desc = 0;
+ kfree(sw_desc);
+}
+
+static struct pxad_desc_sw *
+pxad_alloc_desc(struct pxad_chan *chan, unsigned int nb_hw_desc)
+{
+ struct pxad_desc_sw *sw_desc;
+ dma_addr_t dma;
+ int i;
+
+ sw_desc = kzalloc(sizeof(*sw_desc) +
+ nb_hw_desc * sizeof(struct pxad_desc_hw *),
+ GFP_NOWAIT);
+ if (!sw_desc)
+ return NULL;
+ sw_desc->desc_pool = chan->desc_pool;
+
+ for (i = 0; i < nb_hw_desc; i++) {
+ sw_desc->hw_desc[i] = dma_pool_alloc(sw_desc->desc_pool,
+ GFP_NOWAIT, &dma);
+ if (!sw_desc->hw_desc[i]) {
+ dev_err(&chan->vc.chan.dev->device,
+ "%s(): Couldn't allocate the %dth hw_desc from dma_pool %p\n",
+ __func__, i, sw_desc->desc_pool);
+ goto err;
+ }
+
+ if (i == 0)
+ sw_desc->first = dma;
+ else
+ sw_desc->hw_desc[i - 1]->ddadr = dma;
+ sw_desc->nb_desc++;
+ }
+
+ return sw_desc;
+err:
+ pxad_free_desc(&sw_desc->vd);
+ return NULL;
+}
+
+static dma_cookie_t pxad_tx_submit(struct dma_async_tx_descriptor *tx)
+{
+ struct virt_dma_chan *vc = to_virt_chan(tx->chan);
+ struct pxad_chan *chan = to_pxad_chan(&vc->chan);
+ struct virt_dma_desc *vd_chained = NULL,
+ *vd = container_of(tx, struct virt_dma_desc, tx);
+ dma_cookie_t cookie;
+ unsigned long flags;
+
+ set_updater_desc(to_pxad_sw_desc(vd), tx->flags);
+
+ spin_lock_irqsave(&vc->lock, flags);
+ cookie = dma_cookie_assign(tx);
+
+ if (list_empty(&vc->desc_submitted) && pxad_try_hotchain(vc, vd)) {
+ list_move_tail(&vd->node, &vc->desc_issued);
+ dev_dbg(&chan->vc.chan.dev->device,
+ "%s(): txd %p[%x]: submitted (hot linked)\n",
+ __func__, vd, cookie);
+ goto out;
+ }
+
+ /*
+ * Fallback to placing the tx in the submitted queue
+ */
+ if (!list_empty(&vc->desc_submitted)) {
+ vd_chained = list_entry(vc->desc_submitted.prev,
+ struct virt_dma_desc, node);
+ /*
+ * Only chain the descriptors if no new misalignment is
+ * introduced. If a new misalignment is chained, let the channel
+ * stop, and be relaunched in misalign mode from the irq
+ * handler.
+ */
+ if (chan->misaligned || !to_pxad_sw_desc(vd)->misaligned)
+ pxad_desc_chain(vd_chained, vd);
+ else
+ vd_chained = NULL;
+ }
+ dev_dbg(&chan->vc.chan.dev->device,
+ "%s(): txd %p[%x]: submitted (%s linked)\n",
+ __func__, vd, cookie, vd_chained ? "cold" : "not");
+ list_move_tail(&vd->node, &vc->desc_submitted);
+ chan->misaligned |= to_pxad_sw_desc(vd)->misaligned;
+
+out:
+ spin_unlock_irqrestore(&vc->lock, flags);
+ return cookie;
+}
+
+static void pxad_issue_pending(struct dma_chan *dchan)
+{
+ struct pxad_chan *chan = to_pxad_chan(dchan);
+ struct virt_dma_desc *vd_first;
+ unsigned long flags;
+
+ spin_lock_irqsave(&chan->vc.lock, flags);
+ if (list_empty(&chan->vc.desc_submitted))
+ goto out;
+
+ vd_first = list_first_entry(&chan->vc.desc_submitted,
+ struct virt_dma_desc, node);
+ dev_dbg(&chan->vc.chan.dev->device,
+ "%s(): txd %p[%x]", __func__, vd_first, vd_first->tx.cookie);
+
+ vchan_issue_pending(&chan->vc);
+ if (!pxad_try_hotchain(&chan->vc, vd_first))
+ pxad_launch_chan(chan, to_pxad_sw_desc(vd_first));
+out:
+ spin_unlock_irqrestore(&chan->vc.lock, flags);
+}
+
+static inline struct dma_async_tx_descriptor *
+pxad_tx_prep(struct virt_dma_chan *vc, struct virt_dma_desc *vd,
+ unsigned long tx_flags)
+{
+ struct dma_async_tx_descriptor *tx;
+ struct pxad_chan *chan = container_of(vc, struct pxad_chan, vc);
+
+ tx = vchan_tx_prep(vc, vd, tx_flags);
+ tx->tx_submit = pxad_tx_submit;
+ dev_dbg(&chan->vc.chan.dev->device,
+ "%s(): vc=%p txd=%p[%x] flags=0x%lx\n", __func__,
+ vc, vd, vd->tx.cookie,
+ tx_flags);
+
+ return tx;
+}
+
+static void pxad_get_config(struct pxad_chan *chan,
+ enum dma_transfer_direction dir,
+ u32 *dcmd, u32 *dev_src, u32 *dev_dst)
+{
+ u32 maxburst = 0, dev_addr = 0;
+ enum dma_slave_buswidth width = DMA_SLAVE_BUSWIDTH_UNDEFINED;
+
+ *dcmd = 0;
+ if (chan->cfg.direction == DMA_DEV_TO_MEM) {
+ maxburst = chan->cfg.src_maxburst;
+ width = chan->cfg.src_addr_width;
+ dev_addr = chan->cfg.src_addr;
+ *dev_src = dev_addr;
+ *dcmd |= PXA_DCMD_INCTRGADDR | PXA_DCMD_FLOWSRC;
+ }
+ if (chan->cfg.direction == DMA_MEM_TO_DEV) {
+ maxburst = chan->cfg.dst_maxburst;
+ width = chan->cfg.dst_addr_width;
+ dev_addr = chan->cfg.dst_addr;
+ *dev_dst = dev_addr;
+ *dcmd |= PXA_DCMD_INCSRCADDR | PXA_DCMD_FLOWTRG;
+ }
+ if (chan->cfg.direction == DMA_MEM_TO_MEM)
+ *dcmd |= PXA_DCMD_BURST32 | PXA_DCMD_INCTRGADDR |
+ PXA_DCMD_INCSRCADDR;
+
+ dev_dbg(&chan->vc.chan.dev->device,
+ "%s(): dev_addr=0x%x maxburst=%d width=%d dir=%d\n",
+ __func__, dev_addr, maxburst, width, dir);
+
+ if (width == DMA_SLAVE_BUSWIDTH_1_BYTE)
+ *dcmd |= PXA_DCMD_WIDTH1;
+ else if (width == DMA_SLAVE_BUSWIDTH_2_BYTES)
+ *dcmd |= PXA_DCMD_WIDTH2;
+ else if (width == DMA_SLAVE_BUSWIDTH_4_BYTES)
+ *dcmd |= PXA_DCMD_WIDTH4;
+
+ if (maxburst == 8)
+ *dcmd |= PXA_DCMD_BURST8;
+ else if (maxburst == 16)
+ *dcmd |= PXA_DCMD_BURST16;
+ else if (maxburst == 32)
+ *dcmd |= PXA_DCMD_BURST32;
+
+ /* FIXME: drivers should be ported over to use the filter
+ * function. Once that's done, the following two lines can
+ * be removed.
+ */
+ if (chan->cfg.slave_id)
+ chan->drcmr = chan->cfg.slave_id;
+}
+
+static struct dma_async_tx_descriptor *
+pxad_prep_memcpy(struct dma_chan *dchan,
+ dma_addr_t dma_dst, dma_addr_t dma_src,
+ size_t len, unsigned long flags)
+{
+ struct pxad_chan *chan = to_pxad_chan(dchan);
+ struct pxad_desc_sw *sw_desc;
+ struct pxad_desc_hw *hw_desc;
+ u32 dcmd;
+ unsigned int i, nb_desc = 0;
+ size_t copy;
+
+ if (!dchan || !len)
+ return NULL;
+
+ dev_dbg(&chan->vc.chan.dev->device,
+ "%s(): dma_dst=0x%lx dma_src=0x%lx len=%zu flags=%lx\n",
+ __func__, (unsigned long)dma_dst, (unsigned long)dma_src,
+ len, flags);
+ pxad_get_config(chan, DMA_MEM_TO_MEM, &dcmd, NULL, NULL);
+
+ nb_desc = DIV_ROUND_UP(len, PDMA_MAX_DESC_BYTES);
+ sw_desc = pxad_alloc_desc(chan, nb_desc + 1);
+ if (!sw_desc)
+ return NULL;
+ sw_desc->len = len;
+
+ if (!IS_ALIGNED(dma_src, 1 << PDMA_ALIGNMENT) ||
+ !IS_ALIGNED(dma_dst, 1 << PDMA_ALIGNMENT))
+ sw_desc->misaligned = true;
+
+ i = 0;
+ do {
+ hw_desc = sw_desc->hw_desc[i++];
+ copy = min_t(size_t, len, PDMA_MAX_DESC_BYTES);
+ hw_desc->dcmd = dcmd | (PXA_DCMD_LENGTH & copy);
+ hw_desc->dsadr = dma_src;
+ hw_desc->dtadr = dma_dst;
+ len -= copy;
+ dma_src += copy;
+ dma_dst += copy;
+ } while (len);
+ set_updater_desc(sw_desc, flags);
+
+ return pxad_tx_prep(&chan->vc, &sw_desc->vd, flags);
+}
+
+static struct dma_async_tx_descriptor *
+pxad_prep_slave_sg(struct dma_chan *dchan, struct scatterlist *sgl,
+ unsigned int sg_len, enum dma_transfer_direction dir,
+ unsigned long flags, void *context)
+{
+ struct pxad_chan *chan = to_pxad_chan(dchan);
+ struct pxad_desc_sw *sw_desc;
+ size_t len, avail;
+ struct scatterlist *sg;
+ dma_addr_t dma;
+ u32 dcmd, dsadr = 0, dtadr = 0;
+ unsigned int nb_desc = 0, i, j = 0;
+
+ if ((sgl == NULL) || (sg_len == 0))
+ return NULL;
+
+ pxad_get_config(chan, dir, &dcmd, &dsadr, &dtadr);
+ dev_dbg(&chan->vc.chan.dev->device,
+ "%s(): dir=%d flags=%lx\n", __func__, dir, flags);
+
+ for_each_sg(sgl, sg, sg_len, i)
+ nb_desc += DIV_ROUND_UP(sg_dma_len(sg), PDMA_MAX_DESC_BYTES);
+ sw_desc = pxad_alloc_desc(chan, nb_desc + 1);
+ if (!sw_desc)
+ return NULL;
+
+ for_each_sg(sgl, sg, sg_len, i) {
+ dma = sg_dma_address(sg);
+ avail = sg_dma_len(sg);
+ sw_desc->len += avail;
+
+ do {
+ len = min_t(size_t, avail, PDMA_MAX_DESC_BYTES);
+ if (dma & 0x7)
+ sw_desc->misaligned = true;
+
+ sw_desc->hw_desc[j]->dcmd =
+ dcmd | (PXA_DCMD_LENGTH & len);
+ sw_desc->hw_desc[j]->dsadr = dsadr ? dsadr : dma;
+ sw_desc->hw_desc[j++]->dtadr = dtadr ? dtadr : dma;
+
+ dma += len;
+ avail -= len;
+ } while (avail);
+ }
+ set_updater_desc(sw_desc, flags);
+
+ return pxad_tx_prep(&chan->vc, &sw_desc->vd, flags);
+}
+
+static struct dma_async_tx_descriptor *
+pxad_prep_dma_cyclic(struct dma_chan *dchan,
+ dma_addr_t buf_addr, size_t len, size_t period_len,
+ enum dma_transfer_direction dir, unsigned long flags)
+{
+ struct pxad_chan *chan = to_pxad_chan(dchan);
+ struct pxad_desc_sw *sw_desc;
+ struct pxad_desc_hw **phw_desc;
+ dma_addr_t dma;
+ u32 dcmd, dsadr = 0, dtadr = 0;
+ unsigned int nb_desc = 0;
+
+ if (!dchan || !len || !period_len)
+ return NULL;
+ if ((dir != DMA_DEV_TO_MEM) && (dir != DMA_MEM_TO_DEV)) {
+ dev_err(&chan->vc.chan.dev->device,
+ "Unsupported direction for cyclic DMA\n");
+ return NULL;
+ }
+ /* the buffer length must be a multiple of period_len */
+ if (len % period_len != 0 || period_len > PDMA_MAX_DESC_BYTES ||
+ !IS_ALIGNED(period_len, 1 << PDMA_ALIGNMENT))
+ return NULL;
+
+ pxad_get_config(chan, dir, &dcmd, &dsadr, &dtadr);
+ dcmd |= PXA_DCMD_ENDIRQEN | (PXA_DCMD_LENGTH | period_len);
+ dev_dbg(&chan->vc.chan.dev->device,
+ "%s(): buf_addr=0x%lx len=%zu period=%zu dir=%d flags=%lx\n",
+ __func__, (unsigned long)buf_addr, len, period_len, dir, flags);
+
+ nb_desc = DIV_ROUND_UP(period_len, PDMA_MAX_DESC_BYTES);
+ nb_desc *= DIV_ROUND_UP(len, period_len);
+ sw_desc = pxad_alloc_desc(chan, nb_desc + 1);
+ if (!sw_desc)
+ return NULL;
+ sw_desc->cyclic = true;
+ sw_desc->len = len;
+
+ phw_desc = sw_desc->hw_desc;
+ dma = buf_addr;
+ do {
+ phw_desc[0]->dsadr = dsadr ? dsadr : dma;
+ phw_desc[0]->dtadr = dtadr ? dtadr : dma;
+ phw_desc[0]->dcmd = dcmd;
+ phw_desc++;
+ dma += period_len;
+ len -= period_len;
+ } while (len);
+ set_updater_desc(sw_desc, flags);
+
+ return pxad_tx_prep(&chan->vc, &sw_desc->vd, flags);
+}
+
+static int pxad_config(struct dma_chan *dchan,
+ struct dma_slave_config *cfg)
+{
+ struct pxad_chan *chan = to_pxad_chan(dchan);
+
+ if (!dchan)
+ return -EINVAL;
+
+ chan->cfg = *cfg;
+ return 0;
+}
+
+static int pxad_terminate_all(struct dma_chan *dchan)
+{
+ struct pxad_chan *chan = to_pxad_chan(dchan);
+ struct pxad_device *pdev = to_pxad_dev(chan->vc.chan.device);
+ struct virt_dma_desc *vd = NULL;
+ unsigned long flags;
+ struct pxad_phy *phy;
+ LIST_HEAD(head);
+
+ dev_dbg(&chan->vc.chan.dev->device,
+ "%s(): vchan %p: terminate all\n", __func__, &chan->vc);
+
+ spin_lock_irqsave(&chan->vc.lock, flags);
+ vchan_get_all_descriptors(&chan->vc, &head);
+
+ list_for_each_entry(vd, &head, node) {
+ dev_dbg(&chan->vc.chan.dev->device,
+ "%s(): cancelling txd %p[%x] (completed=%d)", __func__,
+ vd, vd->tx.cookie, is_desc_completed(vd));
+ }
+
+ phy = chan->phy;
+ if (phy) {
+ phy_disable(chan->phy);
+ pxad_free_phy(chan);
+ chan->phy = NULL;
+ spin_lock(&pdev->phy_lock);
+ phy->vchan = NULL;
+ spin_unlock(&pdev->phy_lock);
+ }
+ spin_unlock_irqrestore(&chan->vc.lock, flags);
+ vchan_dma_desc_free_list(&chan->vc, &head);
+
+ return 0;
+}
+
+static unsigned int pxad_residue(struct pxad_chan *chan,
+ dma_cookie_t cookie)
+{
+ struct virt_dma_desc *vd = NULL;
+ struct pxad_desc_sw *sw_desc = NULL;
+ struct pxad_desc_hw *hw_desc = NULL;
+ u32 curr, start, len, end, residue = 0;
+ unsigned long flags;
+ bool passed = false;
+ int i;
+
+ /*
+ * If the channel does not have a phy pointer anymore, it has already
+ * been completed. Therefore, its residue is 0.
+ */
+ if (!chan->phy)
+ return 0;
+
+ spin_lock_irqsave(&chan->vc.lock, flags);
+
+ vd = vchan_find_desc(&chan->vc, cookie);
+ if (!vd)
+ goto out;
+
+ sw_desc = to_pxad_sw_desc(vd);
+ if (sw_desc->hw_desc[0]->dcmd & PXA_DCMD_INCSRCADDR)
+ curr = phy_readl_relaxed(chan->phy, DSADR);
+ else
+ curr = phy_readl_relaxed(chan->phy, DTADR);
+
+ for (i = 0; i < sw_desc->nb_desc - 1; i++) {
+ hw_desc = sw_desc->hw_desc[i];
+ if (sw_desc->hw_desc[0]->dcmd & PXA_DCMD_INCSRCADDR)
+ start = hw_desc->dsadr;
+ else
+ start = hw_desc->dtadr;
+ len = hw_desc->dcmd & PXA_DCMD_LENGTH;
+ end = start + len;
+
+ /*
+ * 'passed' will be latched once we found the descriptor
+ * which lies inside the boundaries of the curr
+ * pointer. All descriptors that occur in the list
+ * _after_ we found that partially handled descriptor
+ * are still to be processed and are hence added to the
+ * residual bytes counter.
+ */
+
+ if (passed) {
+ residue += len;
+ } else if (curr >= start && curr <= end) {
+ residue += end - curr;
+ passed = true;
+ }
+ }
+ if (!passed)
+ residue = sw_desc->len;
+
+out:
+ spin_unlock_irqrestore(&chan->vc.lock, flags);
+ dev_dbg(&chan->vc.chan.dev->device,
+ "%s(): txd %p[%x] sw_desc=%p: %d\n",
+ __func__, vd, cookie, sw_desc, residue);
+ return residue;
+}
+
+static enum dma_status pxad_tx_status(struct dma_chan *dchan,
+ dma_cookie_t cookie,
+ struct dma_tx_state *txstate)
+{
+ struct pxad_chan *chan = to_pxad_chan(dchan);
+ enum dma_status ret;
+
+ ret = dma_cookie_status(dchan, cookie, txstate);
+ if (likely(txstate && (ret != DMA_ERROR)))
+ dma_set_residue(txstate, pxad_residue(chan, cookie));
+
+ return ret;
+}
+
+static void pxad_free_channels(struct dma_device *dmadev)
+{
+ struct pxad_chan *c, *cn;
+
+ list_for_each_entry_safe(c, cn, &dmadev->channels,
+ vc.chan.device_node) {
+ list_del(&c->vc.chan.device_node);
+ tasklet_kill(&c->vc.task);
+ }
+}
+
+static int pxad_remove(struct platform_device *op)
+{
+ struct pxad_device *pdev = platform_get_drvdata(op);
+
+ pxad_cleanup_debugfs(pdev);
+ pxad_free_channels(&pdev->slave);
+ dma_async_device_unregister(&pdev->slave);
+ return 0;
+}
+
+static int pxad_init_phys(struct platform_device *op,
+ struct pxad_device *pdev,
+ unsigned int nb_phy_chans)
+{
+ int irq0, irq, nr_irq = 0, i, ret;
+ struct pxad_phy *phy;
+
+ irq0 = platform_get_irq(op, 0);
+ if (irq0 < 0)
+ return irq0;
+
+ pdev->phys = devm_kcalloc(&op->dev, nb_phy_chans,
+ sizeof(pdev->phys[0]), GFP_KERNEL);
+ if (!pdev->phys)
+ return -ENOMEM;
+
+ for (i = 0; i < nb_phy_chans; i++)
+ if (platform_get_irq(op, i) > 0)
+ nr_irq++;
+
+ for (i = 0; i < nb_phy_chans; i++) {
+ phy = &pdev->phys[i];
+ phy->base = pdev->base;
+ phy->idx = i;
+ irq = platform_get_irq(op, i);
+ if ((nr_irq > 1) && (irq > 0))
+ ret = devm_request_irq(&op->dev, irq,
+ pxad_chan_handler,
+ IRQF_SHARED, "pxa-dma", phy);
+ if ((nr_irq == 1) && (i == 0))
+ ret = devm_request_irq(&op->dev, irq0,
+ pxad_int_handler,
+ IRQF_SHARED, "pxa-dma", pdev);
+ if (ret) {
+ dev_err(pdev->slave.dev,
+ "%s(): can't request irq %d:%d\n", __func__,
+ irq, ret);
+ return ret;
+ }
+ }
+
+ return 0;
+}
+
+static const struct of_device_id const pxad_dt_ids[] = {
+ { .compatible = "marvell,pdma-1.0", },
+ {}
+};
+MODULE_DEVICE_TABLE(of, pxad_dt_ids);
+
+static struct dma_chan *pxad_dma_xlate(struct of_phandle_args *dma_spec,
+ struct of_dma *ofdma)
+{
+ struct pxad_device *d = ofdma->of_dma_data;
+ struct dma_chan *chan;
+
+ chan = dma_get_any_slave_channel(&d->slave);
+ if (!chan)
+ return NULL;
+
+ to_pxad_chan(chan)->drcmr = dma_spec->args[0];
+ to_pxad_chan(chan)->prio = dma_spec->args[1];
+
+ return chan;
+}
+
+static int pxad_init_dmadev(struct platform_device *op,
+ struct pxad_device *pdev,
+ unsigned int nr_phy_chans)
+{
+ int ret;
+ unsigned int i;
+ struct pxad_chan *c;
+
+ pdev->nr_chans = nr_phy_chans;
+ INIT_LIST_HEAD(&pdev->slave.channels);
+ pdev->slave.device_alloc_chan_resources = pxad_alloc_chan_resources;
+ pdev->slave.device_free_chan_resources = pxad_free_chan_resources;
+ pdev->slave.device_tx_status = pxad_tx_status;
+ pdev->slave.device_issue_pending = pxad_issue_pending;
+ pdev->slave.device_config = pxad_config;
+ pdev->slave.device_terminate_all = pxad_terminate_all;
+
+ if (op->dev.coherent_dma_mask)
+ dma_set_mask(&op->dev, op->dev.coherent_dma_mask);
+ else
+ dma_set_mask(&op->dev, DMA_BIT_MASK(32));
+
+ ret = pxad_init_phys(op, pdev, nr_phy_chans);
+ if (ret)
+ return ret;
+
+ for (i = 0; i < nr_phy_chans; i++) {
+ c = devm_kzalloc(&op->dev, sizeof(*c), GFP_KERNEL);
+ if (!c)
+ return -ENOMEM;
+ c->vc.desc_free = pxad_free_desc;
+ vchan_init(&c->vc, &pdev->slave);
+ }
+
+ return dma_async_device_register(&pdev->slave);
+}
+
+static int pxad_probe(struct platform_device *op)
+{
+ struct pxad_device *pdev;
+ const struct of_device_id *of_id;
+ struct mmp_dma_platdata *pdata = dev_get_platdata(&op->dev);
+ struct resource *iores;
+ int ret, dma_channels = 0;
+ const enum dma_slave_buswidth widths =
+ DMA_SLAVE_BUSWIDTH_1_BYTE | DMA_SLAVE_BUSWIDTH_2_BYTES |
+ DMA_SLAVE_BUSWIDTH_4_BYTES;
+
+ pdev = devm_kzalloc(&op->dev, sizeof(*pdev), GFP_KERNEL);
+ if (!pdev)
+ return -ENOMEM;
+
+ spin_lock_init(&pdev->phy_lock);
+
+ iores = platform_get_resource(op, IORESOURCE_MEM, 0);
+ pdev->base = devm_ioremap_resource(&op->dev, iores);
+ if (IS_ERR(pdev->base))
+ return PTR_ERR(pdev->base);
+
+ of_id = of_match_device(pxad_dt_ids, &op->dev);
+ if (of_id)
+ of_property_read_u32(op->dev.of_node, "#dma-channels",
+ &dma_channels);
+ else if (pdata && pdata->dma_channels)
+ dma_channels = pdata->dma_channels;
+ else
+ dma_channels = 32; /* default 32 channel */
+
+ dma_cap_set(DMA_SLAVE, pdev->slave.cap_mask);
+ dma_cap_set(DMA_MEMCPY, pdev->slave.cap_mask);
+ dma_cap_set(DMA_CYCLIC, pdev->slave.cap_mask);
+ dma_cap_set(DMA_PRIVATE, pdev->slave.cap_mask);
+ pdev->slave.device_prep_dma_memcpy = pxad_prep_memcpy;
+ pdev->slave.device_prep_slave_sg = pxad_prep_slave_sg;
+ pdev->slave.device_prep_dma_cyclic = pxad_prep_dma_cyclic;
+
+ pdev->slave.copy_align = PDMA_ALIGNMENT;
+ pdev->slave.src_addr_widths = widths;
+ pdev->slave.dst_addr_widths = widths;
+ pdev->slave.directions = BIT(DMA_MEM_TO_DEV) | BIT(DMA_DEV_TO_MEM);
+ pdev->slave.residue_granularity = DMA_RESIDUE_GRANULARITY_DESCRIPTOR;
+
+ pdev->slave.dev = &op->dev;
+ ret = pxad_init_dmadev(op, pdev, dma_channels);
+ if (ret) {
+ dev_err(pdev->slave.dev, "unable to register\n");
+ return ret;
+ }
+
+ if (op->dev.of_node) {
+ /* Device-tree DMA controller registration */
+ ret = of_dma_controller_register(op->dev.of_node,
+ pxad_dma_xlate, pdev);
+ if (ret < 0) {
+ dev_err(pdev->slave.dev,
+ "of_dma_controller_register failed\n");
+ return ret;
+ }
+ }
+
+ platform_set_drvdata(op, pdev);
+ pxad_init_debugfs(pdev);
+ dev_info(pdev->slave.dev, "initialized %d channels\n", dma_channels);
+ return 0;
+}
+
+static const struct platform_device_id pxad_id_table[] = {
+ { "pxa-dma", },
+ { },
+};
+
+static struct platform_driver pxad_driver = {
+ .driver = {
+ .name = "pxa-dma",
+ .of_match_table = pxad_dt_ids,
+ },
+ .id_table = pxad_id_table,
+ .probe = pxad_probe,
+ .remove = pxad_remove,
+};
+
+bool pxad_filter_fn(struct dma_chan *chan, void *param)
+{
+ struct pxad_chan *c = to_pxad_chan(chan);
+ struct pxad_param *p = param;
+
+ if (chan->device->dev->driver != &pxad_driver.driver)
+ return false;
+
+ c->drcmr = p->drcmr;
+ c->prio = p->prio;
+
+ return true;
+}
+EXPORT_SYMBOL_GPL(pxad_filter_fn);
+
+int pxad_toggle_reserved_channel(int legacy_channel)
+{
+ if (legacy_unavailable & (BIT(legacy_channel)))
+ return -EBUSY;
+ legacy_reserved ^= BIT(legacy_channel);
+ return 0;
+}
+EXPORT_SYMBOL_GPL(pxad_toggle_reserved_channel);
+
+module_platform_driver(pxad_driver);
+
+MODULE_DESCRIPTION("Marvell PXA Peripheral DMA Driver");
+MODULE_AUTHOR("Robert Jarzmik <robert.jarzmik@free.fr>");
+MODULE_LICENSE("GPL v2");
diff --git a/include/linux/dma/pxa-dma.h b/include/linux/dma/pxa-dma.h
new file mode 100644
index 0000000..3edc992
--- /dev/null
+++ b/include/linux/dma/pxa-dma.h
@@ -0,0 +1,27 @@
+#ifndef _PXA_DMA_H_
+#define _PXA_DMA_H_
+
+enum pxad_chan_prio {
+ PXAD_PRIO_HIGHEST = 0,
+ PXAD_PRIO_NORMAL,
+ PXAD_PRIO_LOW,
+ PXAD_PRIO_LOWEST,
+};
+
+struct pxad_param {
+ unsigned int drcmr;
+ enum pxad_chan_prio prio;
+};
+
+struct dma_chan;
+
+#ifdef CONFIG_PXA_DMA
+bool pxad_filter_fn(struct dma_chan *chan, void *param);
+#else
+static inline bool pxad_filter_fn(struct dma_chan *chan, void *param)
+{
+ return false;
+}
+#endif
+
+#endif /* _PXA_DMA_H_ */
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