From: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
To: Hans-Christian Noren Egtvedt <egtvedt@samfundet.no>,
linux-kernel@vger.kernel.org,
Haavard Skinnemoen <hskinnemoen@gmail.com>,
Nicolas Ferre <nicolas.ferre@atmel.com>,
Boris Brezillon <boris.brezillon@free-electrons.com>,
Mark Brown <broonie@kernel.org>,
Liam Girdwood <lgirdwood@gmail.com>,
alsa-devel@alsa-project.org, Vinod Koul <vinod.koul@intel.com>,
dmaengine@vger.kernel.org,
Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Subject: [PATCH v2 2/2] dmaengine: dw: Remove AVR32 bits from the driver
Date: Tue, 9 May 2017 19:18:37 +0300 [thread overview]
Message-ID: <20170509161837.48301-3-andriy.shevchenko@linux.intel.com> (raw)
In-Reply-To: <20170509161837.48301-1-andriy.shevchenko@linux.intel.com>
AVR32 is gone. Now it's time to clean up the driver by removing
leftovers that was used by AVR32 related code.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
drivers/dma/dw/Kconfig | 7 +-
drivers/dma/dw/core.c | 332 +------------------------------------------------
drivers/dma/dw/regs.h | 50 ++------
include/linux/dma/dw.h | 21 ----
4 files changed, 14 insertions(+), 396 deletions(-)
diff --git a/drivers/dma/dw/Kconfig b/drivers/dma/dw/Kconfig
index 5a37b9fcf40d..04b9728c1d26 100644
--- a/drivers/dma/dw/Kconfig
+++ b/drivers/dma/dw/Kconfig
@@ -6,17 +6,12 @@ config DW_DMAC_CORE
tristate
select DMA_ENGINE
-config DW_DMAC_BIG_ENDIAN_IO
- bool
-
config DW_DMAC
tristate "Synopsys DesignWare AHB DMA platform driver"
select DW_DMAC_CORE
- select DW_DMAC_BIG_ENDIAN_IO if AVR32
- default y if CPU_AT32AP7000
help
Support the Synopsys DesignWare AHB DMA controller. This
- can be integrated in chips such as the Atmel AT32ap7000.
+ can be integrated in chips such as the Intel Cherrytrail.
config DW_DMAC_PCI
tristate "Synopsys DesignWare AHB DMA PCI driver"
diff --git a/drivers/dma/dw/core.c b/drivers/dma/dw/core.c
index e500950dad82..f43e6dafe446 100644
--- a/drivers/dma/dw/core.c
+++ b/drivers/dma/dw/core.c
@@ -561,92 +561,14 @@ static void dwc_handle_error(struct dw_dma *dw, struct dw_dma_chan *dwc)
dwc_descriptor_complete(dwc, bad_desc, true);
}
-/* --------------------- Cyclic DMA API extensions -------------------- */
-
-dma_addr_t dw_dma_get_src_addr(struct dma_chan *chan)
-{
- struct dw_dma_chan *dwc = to_dw_dma_chan(chan);
- return channel_readl(dwc, SAR);
-}
-EXPORT_SYMBOL(dw_dma_get_src_addr);
-
-dma_addr_t dw_dma_get_dst_addr(struct dma_chan *chan)
-{
- struct dw_dma_chan *dwc = to_dw_dma_chan(chan);
- return channel_readl(dwc, DAR);
-}
-EXPORT_SYMBOL(dw_dma_get_dst_addr);
-
-/* Called with dwc->lock held and all DMAC interrupts disabled */
-static void dwc_handle_cyclic(struct dw_dma *dw, struct dw_dma_chan *dwc,
- u32 status_block, u32 status_err, u32 status_xfer)
-{
- unsigned long flags;
-
- if (status_block & dwc->mask) {
- void (*callback)(void *param);
- void *callback_param;
-
- dev_vdbg(chan2dev(&dwc->chan), "new cyclic period llp 0x%08x\n",
- channel_readl(dwc, LLP));
- dma_writel(dw, CLEAR.BLOCK, dwc->mask);
-
- callback = dwc->cdesc->period_callback;
- callback_param = dwc->cdesc->period_callback_param;
-
- if (callback)
- callback(callback_param);
- }
-
- /*
- * Error and transfer complete are highly unlikely, and will most
- * likely be due to a configuration error by the user.
- */
- if (unlikely(status_err & dwc->mask) ||
- unlikely(status_xfer & dwc->mask)) {
- unsigned int i;
-
- dev_err(chan2dev(&dwc->chan),
- "cyclic DMA unexpected %s interrupt, stopping DMA transfer\n",
- status_xfer ? "xfer" : "error");
-
- spin_lock_irqsave(&dwc->lock, flags);
-
- dwc_dump_chan_regs(dwc);
-
- dwc_chan_disable(dw, dwc);
-
- /* Make sure DMA does not restart by loading a new list */
- channel_writel(dwc, LLP, 0);
- channel_writel(dwc, CTL_LO, 0);
- channel_writel(dwc, CTL_HI, 0);
-
- dma_writel(dw, CLEAR.BLOCK, dwc->mask);
- dma_writel(dw, CLEAR.ERROR, dwc->mask);
- dma_writel(dw, CLEAR.XFER, dwc->mask);
-
- for (i = 0; i < dwc->cdesc->periods; i++)
- dwc_dump_lli(dwc, dwc->cdesc->desc[i]);
-
- spin_unlock_irqrestore(&dwc->lock, flags);
- }
-
- /* Re-enable interrupts */
- channel_set_bit(dw, MASK.BLOCK, dwc->mask);
-}
-
-/* ------------------------------------------------------------------------- */
-
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;
unsigned int i;
- status_block = dma_readl(dw, RAW.BLOCK);
status_xfer = dma_readl(dw, RAW.XFER);
status_err = dma_readl(dw, RAW.ERROR);
@@ -655,8 +577,7 @@ static void dw_dma_tasklet(unsigned long data)
for (i = 0; i < dw->dma.chancnt; i++) {
dwc = &dw->chan[i];
if (test_bit(DW_DMA_IS_CYCLIC, &dwc->flags))
- dwc_handle_cyclic(dw, dwc, status_block, status_err,
- status_xfer);
+ dev_vdbg(dw->dma.dev, "Cyclic xfer is not implemented\n");
else if (status_err & (1 << i))
dwc_handle_error(dw, dwc);
else if (status_xfer & (1 << i))
@@ -1264,255 +1185,6 @@ static void dwc_free_chan_resources(struct dma_chan *chan)
dev_vdbg(chan2dev(chan), "%s: done\n", __func__);
}
-/* --------------------- Cyclic DMA API extensions -------------------- */
-
-/**
- * dw_dma_cyclic_start - start the cyclic DMA transfer
- * @chan: the DMA channel to start
- *
- * Must be called with soft interrupts disabled. Returns zero on success or
- * -errno on failure.
- */
-int dw_dma_cyclic_start(struct dma_chan *chan)
-{
- struct dw_dma_chan *dwc = to_dw_dma_chan(chan);
- struct dw_dma *dw = to_dw_dma(chan->device);
- unsigned long flags;
-
- if (!test_bit(DW_DMA_IS_CYCLIC, &dwc->flags)) {
- dev_err(chan2dev(&dwc->chan), "missing prep for cyclic DMA\n");
- return -ENODEV;
- }
-
- spin_lock_irqsave(&dwc->lock, flags);
-
- /* Enable interrupts to perform cyclic transfer */
- channel_set_bit(dw, MASK.BLOCK, dwc->mask);
-
- dwc_dostart(dwc, dwc->cdesc->desc[0]);
-
- spin_unlock_irqrestore(&dwc->lock, flags);
-
- return 0;
-}
-EXPORT_SYMBOL(dw_dma_cyclic_start);
-
-/**
- * dw_dma_cyclic_stop - stop the cyclic DMA transfer
- * @chan: the DMA channel to stop
- *
- * Must be called with soft interrupts disabled.
- */
-void dw_dma_cyclic_stop(struct dma_chan *chan)
-{
- struct dw_dma_chan *dwc = to_dw_dma_chan(chan);
- struct dw_dma *dw = to_dw_dma(dwc->chan.device);
- unsigned long flags;
-
- spin_lock_irqsave(&dwc->lock, flags);
-
- dwc_chan_disable(dw, dwc);
-
- spin_unlock_irqrestore(&dwc->lock, flags);
-}
-EXPORT_SYMBOL(dw_dma_cyclic_stop);
-
-/**
- * dw_dma_cyclic_prep - prepare the cyclic DMA transfer
- * @chan: the DMA channel to prepare
- * @buf_addr: physical DMA address where the buffer starts
- * @buf_len: total number of bytes for the entire buffer
- * @period_len: number of bytes for each period
- * @direction: transfer direction, to or from device
- *
- * Must be called before trying to start the transfer. Returns a valid struct
- * dw_cyclic_desc if successful or an ERR_PTR(-errno) if not successful.
- */
-struct dw_cyclic_desc *dw_dma_cyclic_prep(struct dma_chan *chan,
- dma_addr_t buf_addr, size_t buf_len, size_t period_len,
- enum dma_transfer_direction direction)
-{
- struct dw_dma_chan *dwc = to_dw_dma_chan(chan);
- struct dma_slave_config *sconfig = &dwc->dma_sconfig;
- struct dw_cyclic_desc *cdesc;
- struct dw_cyclic_desc *retval = NULL;
- struct dw_desc *desc;
- struct dw_desc *last = NULL;
- u8 lms = DWC_LLP_LMS(dwc->dws.m_master);
- unsigned long was_cyclic;
- unsigned int reg_width;
- unsigned int periods;
- unsigned int i;
- unsigned long flags;
-
- spin_lock_irqsave(&dwc->lock, flags);
- if (dwc->nollp) {
- spin_unlock_irqrestore(&dwc->lock, flags);
- dev_dbg(chan2dev(&dwc->chan),
- "channel doesn't support LLP transfers\n");
- return ERR_PTR(-EINVAL);
- }
-
- if (!list_empty(&dwc->queue) || !list_empty(&dwc->active_list)) {
- spin_unlock_irqrestore(&dwc->lock, flags);
- dev_dbg(chan2dev(&dwc->chan),
- "queue and/or active list are not empty\n");
- return ERR_PTR(-EBUSY);
- }
-
- was_cyclic = test_and_set_bit(DW_DMA_IS_CYCLIC, &dwc->flags);
- spin_unlock_irqrestore(&dwc->lock, flags);
- if (was_cyclic) {
- dev_dbg(chan2dev(&dwc->chan),
- "channel already prepared for cyclic DMA\n");
- return ERR_PTR(-EBUSY);
- }
-
- retval = ERR_PTR(-EINVAL);
-
- if (unlikely(!is_slave_direction(direction)))
- goto out_err;
-
- dwc->direction = direction;
-
- if (direction == DMA_MEM_TO_DEV)
- reg_width = __ffs(sconfig->dst_addr_width);
- else
- reg_width = __ffs(sconfig->src_addr_width);
-
- periods = buf_len / period_len;
-
- /* Check for too big/unaligned periods and unaligned DMA buffer. */
- if (period_len > (dwc->block_size << reg_width))
- goto out_err;
- if (unlikely(period_len & ((1 << reg_width) - 1)))
- goto out_err;
- if (unlikely(buf_addr & ((1 << reg_width) - 1)))
- goto out_err;
-
- retval = ERR_PTR(-ENOMEM);
-
- cdesc = kzalloc(sizeof(struct dw_cyclic_desc), GFP_KERNEL);
- if (!cdesc)
- goto out_err;
-
- cdesc->desc = kzalloc(sizeof(struct dw_desc *) * periods, GFP_KERNEL);
- if (!cdesc->desc)
- goto out_err_alloc;
-
- for (i = 0; i < periods; i++) {
- desc = dwc_desc_get(dwc);
- if (!desc)
- goto out_err_desc_get;
-
- switch (direction) {
- case DMA_MEM_TO_DEV:
- lli_write(desc, dar, sconfig->dst_addr);
- lli_write(desc, sar, buf_addr + period_len * i);
- lli_write(desc, ctllo, (DWC_DEFAULT_CTLLO(chan)
- | DWC_CTLL_DST_WIDTH(reg_width)
- | DWC_CTLL_SRC_WIDTH(reg_width)
- | DWC_CTLL_DST_FIX
- | DWC_CTLL_SRC_INC
- | DWC_CTLL_INT_EN));
-
- lli_set(desc, ctllo, sconfig->device_fc ?
- DWC_CTLL_FC(DW_DMA_FC_P_M2P) :
- DWC_CTLL_FC(DW_DMA_FC_D_M2P));
-
- break;
- case DMA_DEV_TO_MEM:
- lli_write(desc, dar, buf_addr + period_len * i);
- lli_write(desc, sar, sconfig->src_addr);
- lli_write(desc, ctllo, (DWC_DEFAULT_CTLLO(chan)
- | DWC_CTLL_SRC_WIDTH(reg_width)
- | DWC_CTLL_DST_WIDTH(reg_width)
- | DWC_CTLL_DST_INC
- | DWC_CTLL_SRC_FIX
- | DWC_CTLL_INT_EN));
-
- lli_set(desc, ctllo, sconfig->device_fc ?
- DWC_CTLL_FC(DW_DMA_FC_P_P2M) :
- DWC_CTLL_FC(DW_DMA_FC_D_P2M));
-
- break;
- default:
- break;
- }
-
- lli_write(desc, ctlhi, period_len >> reg_width);
- cdesc->desc[i] = desc;
-
- if (last)
- lli_write(last, llp, desc->txd.phys | lms);
-
- last = desc;
- }
-
- /* Let's make a cyclic list */
- lli_write(last, llp, cdesc->desc[0]->txd.phys | lms);
-
- dev_dbg(chan2dev(&dwc->chan),
- "cyclic prepared buf %pad len %zu period %zu periods %d\n",
- &buf_addr, buf_len, period_len, periods);
-
- cdesc->periods = periods;
- dwc->cdesc = cdesc;
-
- return cdesc;
-
-out_err_desc_get:
- while (i--)
- dwc_desc_put(dwc, cdesc->desc[i]);
-out_err_alloc:
- kfree(cdesc);
-out_err:
- clear_bit(DW_DMA_IS_CYCLIC, &dwc->flags);
- return (struct dw_cyclic_desc *)retval;
-}
-EXPORT_SYMBOL(dw_dma_cyclic_prep);
-
-/**
- * dw_dma_cyclic_free - free a prepared cyclic DMA transfer
- * @chan: the DMA channel to free
- */
-void dw_dma_cyclic_free(struct dma_chan *chan)
-{
- struct dw_dma_chan *dwc = to_dw_dma_chan(chan);
- struct dw_dma *dw = to_dw_dma(dwc->chan.device);
- struct dw_cyclic_desc *cdesc = dwc->cdesc;
- unsigned int i;
- unsigned long flags;
-
- dev_dbg(chan2dev(&dwc->chan), "%s\n", __func__);
-
- if (!cdesc)
- return;
-
- spin_lock_irqsave(&dwc->lock, flags);
-
- dwc_chan_disable(dw, dwc);
-
- dma_writel(dw, CLEAR.BLOCK, dwc->mask);
- dma_writel(dw, CLEAR.ERROR, dwc->mask);
- dma_writel(dw, CLEAR.XFER, dwc->mask);
-
- spin_unlock_irqrestore(&dwc->lock, flags);
-
- for (i = 0; i < cdesc->periods; i++)
- dwc_desc_put(dwc, cdesc->desc[i]);
-
- kfree(cdesc->desc);
- kfree(cdesc);
-
- dwc->cdesc = NULL;
-
- clear_bit(DW_DMA_IS_CYCLIC, &dwc->flags);
-}
-EXPORT_SYMBOL(dw_dma_cyclic_free);
-
-/*----------------------------------------------------------------------*/
-
int dw_dma_probe(struct dw_dma_chip *chip)
{
struct dw_dma_platform_data *pdata;
@@ -1642,7 +1314,7 @@ int dw_dma_probe(struct dw_dma_chip *chip)
if (autocfg) {
unsigned int r = DW_DMA_MAX_NR_CHANNELS - i - 1;
void __iomem *addr = &__dw_regs(dw)->DWC_PARAMS[r];
- unsigned int dwc_params = dma_readl_native(addr);
+ unsigned int dwc_params = readl(addr);
dev_dbg(chip->dev, "DWC_PARAMS[%d]: 0x%08x\n", i,
dwc_params);
diff --git a/drivers/dma/dw/regs.h b/drivers/dma/dw/regs.h
index 32a328721c88..09e7dfdbb790 100644
--- a/drivers/dma/dw/regs.h
+++ b/drivers/dma/dw/regs.h
@@ -116,20 +116,6 @@ struct dw_dma_regs {
DW_REG(GLOBAL_CFG);
};
-/*
- * Big endian I/O access when reading and writing to the DMA controller
- * registers. This is needed on some platforms, like the Atmel AVR32
- * architecture.
- */
-
-#ifdef CONFIG_DW_DMAC_BIG_ENDIAN_IO
-#define dma_readl_native ioread32be
-#define dma_writel_native iowrite32be
-#else
-#define dma_readl_native readl
-#define dma_writel_native writel
-#endif
-
/* Bitfields in DW_PARAMS */
#define DW_PARAMS_NR_CHAN 8 /* number of channels */
#define DW_PARAMS_NR_MASTER 11 /* number of AHB masters */
@@ -280,7 +266,6 @@ struct dw_dma_chan {
unsigned long flags;
struct list_head active_list;
struct list_head queue;
- struct dw_cyclic_desc *cdesc;
unsigned int descs_allocated;
@@ -302,9 +287,9 @@ __dwc_regs(struct dw_dma_chan *dwc)
}
#define channel_readl(dwc, name) \
- dma_readl_native(&(__dwc_regs(dwc)->name))
+ readl(&(__dwc_regs(dwc)->name))
#define channel_writel(dwc, name, val) \
- dma_writel_native((val), &(__dwc_regs(dwc)->name))
+ writel((val), &(__dwc_regs(dwc)->name))
static inline struct dw_dma_chan *to_dw_dma_chan(struct dma_chan *chan)
{
@@ -333,9 +318,9 @@ static inline struct dw_dma_regs __iomem *__dw_regs(struct dw_dma *dw)
}
#define dma_readl(dw, name) \
- dma_readl_native(&(__dw_regs(dw)->name))
+ readl(&(__dw_regs(dw)->name))
#define dma_writel(dw, name, val) \
- dma_writel_native((val), &(__dw_regs(dw)->name))
+ writel((val), &(__dw_regs(dw)->name))
#define idma32_readq(dw, name) \
hi_lo_readq(&(__dw_regs(dw)->name))
@@ -352,43 +337,30 @@ static inline struct dw_dma *to_dw_dma(struct dma_device *ddev)
return container_of(ddev, struct dw_dma, dma);
}
-#ifdef CONFIG_DW_DMAC_BIG_ENDIAN_IO
-typedef __be32 __dw32;
-#else
-typedef __le32 __dw32;
-#endif
-
/* LLI == Linked List Item; a.k.a. DMA block descriptor */
struct dw_lli {
/* values that are not changed by hardware */
- __dw32 sar;
- __dw32 dar;
- __dw32 llp; /* chain to next lli */
- __dw32 ctllo;
+ __le32 sar;
+ __le32 dar;
+ __le32 llp; /* chain to next lli */
+ __le32 ctllo;
/* values that may get written back: */
- __dw32 ctlhi;
+ __le32 ctlhi;
/* sstat and dstat can snapshot peripheral register state.
* silicon config may discard either or both...
*/
- __dw32 sstat;
- __dw32 dstat;
+ __le32 sstat;
+ __le32 dstat;
};
struct dw_desc {
/* FIRST values the hardware uses */
struct dw_lli lli;
-#ifdef CONFIG_DW_DMAC_BIG_ENDIAN_IO
-#define lli_set(d, reg, v) ((d)->lli.reg |= cpu_to_be32(v))
-#define lli_clear(d, reg, v) ((d)->lli.reg &= ~cpu_to_be32(v))
-#define lli_read(d, reg) be32_to_cpu((d)->lli.reg)
-#define lli_write(d, reg, v) ((d)->lli.reg = cpu_to_be32(v))
-#else
#define lli_set(d, reg, v) ((d)->lli.reg |= cpu_to_le32(v))
#define lli_clear(d, reg, v) ((d)->lli.reg &= ~cpu_to_le32(v))
#define lli_read(d, reg) le32_to_cpu((d)->lli.reg)
#define lli_write(d, reg, v) ((d)->lli.reg = cpu_to_le32(v))
-#endif
/* THEN values for driver housekeeping */
struct list_head desc_node;
diff --git a/include/linux/dma/dw.h b/include/linux/dma/dw.h
index b63b25814d77..e166cac8e870 100644
--- a/include/linux/dma/dw.h
+++ b/include/linux/dma/dw.h
@@ -50,25 +50,4 @@ static inline int dw_dma_probe(struct dw_dma_chip *chip) { return -ENODEV; }
static inline int dw_dma_remove(struct dw_dma_chip *chip) { return 0; }
#endif /* CONFIG_DW_DMAC_CORE */
-/* DMA API extensions */
-struct dw_desc;
-
-struct dw_cyclic_desc {
- struct dw_desc **desc;
- unsigned long periods;
- void (*period_callback)(void *param);
- void *period_callback_param;
-};
-
-struct dw_cyclic_desc *dw_dma_cyclic_prep(struct dma_chan *chan,
- dma_addr_t buf_addr, size_t buf_len, size_t period_len,
- enum dma_transfer_direction direction);
-void dw_dma_cyclic_free(struct dma_chan *chan);
-int dw_dma_cyclic_start(struct dma_chan *chan);
-void dw_dma_cyclic_stop(struct dma_chan *chan);
-
-dma_addr_t dw_dma_get_src_addr(struct dma_chan *chan);
-
-dma_addr_t dw_dma_get_dst_addr(struct dma_chan *chan);
-
#endif /* _DMA_DW_H */
--
2.11.0
next prev parent reply other threads:[~2017-05-09 16:19 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-05-09 16:18 [PATCH v2 0/2] ALSA, dmaengine: dw: Remove AVR32 bits in drivers Andy Shevchenko
2017-05-09 16:18 ` [PATCH v2 1/2] ALSA: atmel: Remove AVR32 bits from the driver Andy Shevchenko
2017-05-09 16:18 ` Andy Shevchenko [this message]
2017-05-14 13:04 ` [PATCH v2 2/2] dmaengine: dw: " Vinod Koul
2017-05-14 13:04 ` Vinod Koul
2017-05-15 8:43 ` Andy Shevchenko
2017-05-15 8:43 ` Andy Shevchenko
2017-05-15 9:25 ` Lars-Peter Clausen
2017-05-15 9:42 ` Andy Shevchenko
2017-05-15 9:42 ` Andy Shevchenko
2017-05-15 14:49 ` [alsa-devel] " Vinod Koul
2017-05-15 14:49 ` Vinod Koul
2017-05-15 15:09 ` [alsa-devel] " Takashi Iwai
2017-05-16 4:28 ` Vinod Koul
2017-05-17 8:20 ` Andy Shevchenko
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