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-rw-r--r--drivers/dma/dw/dw.c137
1 files changed, 137 insertions, 0 deletions
diff --git a/drivers/dma/dw/dw.c b/drivers/dma/dw/dw.c
new file mode 100644
index 000000000..a4862263f
--- /dev/null
+++ b/drivers/dma/dw/dw.c
@@ -0,0 +1,137 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2007-2008 Atmel Corporation
+// Copyright (C) 2010-2011 ST Microelectronics
+// Copyright (C) 2013,2018 Intel Corporation
+
+#include <linux/bitops.h>
+#include <linux/dmaengine.h>
+#include <linux/errno.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+
+#include "internal.h"
+
+static void dw_dma_initialize_chan(struct dw_dma_chan *dwc)
+{
+ struct dw_dma *dw = to_dw_dma(dwc->chan.device);
+ u32 cfghi = is_slave_direction(dwc->direction) ? 0 : DWC_CFGH_FIFO_MODE;
+ u32 cfglo = DWC_CFGL_CH_PRIOR(dwc->priority);
+ bool hs_polarity = dwc->dws.hs_polarity;
+
+ cfghi |= DWC_CFGH_DST_PER(dwc->dws.dst_id);
+ cfghi |= DWC_CFGH_SRC_PER(dwc->dws.src_id);
+ cfghi |= DWC_CFGH_PROTCTL(dw->pdata->protctl);
+
+ /* Set polarity of handshake interface */
+ cfglo |= hs_polarity ? DWC_CFGL_HS_DST_POL | DWC_CFGL_HS_SRC_POL : 0;
+
+ channel_writel(dwc, CFG_LO, cfglo);
+ channel_writel(dwc, CFG_HI, cfghi);
+}
+
+static void dw_dma_suspend_chan(struct dw_dma_chan *dwc, bool drain)
+{
+ u32 cfglo = channel_readl(dwc, CFG_LO);
+
+ channel_writel(dwc, CFG_LO, cfglo | DWC_CFGL_CH_SUSP);
+}
+
+static void dw_dma_resume_chan(struct dw_dma_chan *dwc, bool drain)
+{
+ u32 cfglo = channel_readl(dwc, CFG_LO);
+
+ channel_writel(dwc, CFG_LO, cfglo & ~DWC_CFGL_CH_SUSP);
+}
+
+static u32 dw_dma_bytes2block(struct dw_dma_chan *dwc,
+ size_t bytes, unsigned int width, size_t *len)
+{
+ u32 block;
+
+ if ((bytes >> width) > dwc->block_size) {
+ block = dwc->block_size;
+ *len = dwc->block_size << width;
+ } else {
+ block = bytes >> width;
+ *len = bytes;
+ }
+
+ return block;
+}
+
+static size_t dw_dma_block2bytes(struct dw_dma_chan *dwc, u32 block, u32 width)
+{
+ return DWC_CTLH_BLOCK_TS(block) << width;
+}
+
+static u32 dw_dma_prepare_ctllo(struct dw_dma_chan *dwc)
+{
+ struct dma_slave_config *sconfig = &dwc->dma_sconfig;
+ u8 smsize = (dwc->direction == DMA_DEV_TO_MEM) ? sconfig->src_maxburst : 0;
+ u8 dmsize = (dwc->direction == DMA_MEM_TO_DEV) ? sconfig->dst_maxburst : 0;
+ u8 p_master = dwc->dws.p_master;
+ u8 m_master = dwc->dws.m_master;
+ u8 dms = (dwc->direction == DMA_MEM_TO_DEV) ? p_master : m_master;
+ u8 sms = (dwc->direction == DMA_DEV_TO_MEM) ? p_master : m_master;
+
+ return DWC_CTLL_LLP_D_EN | DWC_CTLL_LLP_S_EN |
+ DWC_CTLL_DST_MSIZE(dmsize) | DWC_CTLL_SRC_MSIZE(smsize) |
+ DWC_CTLL_DMS(dms) | DWC_CTLL_SMS(sms);
+}
+
+static void dw_dma_encode_maxburst(struct dw_dma_chan *dwc, u32 *maxburst)
+{
+ /*
+ * Fix burst size according to dw_dmac. We need to convert them as:
+ * 1 -> 0, 4 -> 1, 8 -> 2, 16 -> 3.
+ */
+ *maxburst = *maxburst > 1 ? fls(*maxburst) - 2 : 0;
+}
+
+static void dw_dma_set_device_name(struct dw_dma *dw, int id)
+{
+ snprintf(dw->name, sizeof(dw->name), "dw:dmac%d", id);
+}
+
+static void dw_dma_disable(struct dw_dma *dw)
+{
+ do_dw_dma_off(dw);
+}
+
+static void dw_dma_enable(struct dw_dma *dw)
+{
+ do_dw_dma_on(dw);
+}
+
+int dw_dma_probe(struct dw_dma_chip *chip)
+{
+ struct dw_dma *dw;
+
+ dw = devm_kzalloc(chip->dev, sizeof(*dw), GFP_KERNEL);
+ if (!dw)
+ return -ENOMEM;
+
+ /* Channel operations */
+ dw->initialize_chan = dw_dma_initialize_chan;
+ dw->suspend_chan = dw_dma_suspend_chan;
+ dw->resume_chan = dw_dma_resume_chan;
+ dw->prepare_ctllo = dw_dma_prepare_ctllo;
+ dw->encode_maxburst = dw_dma_encode_maxburst;
+ dw->bytes2block = dw_dma_bytes2block;
+ dw->block2bytes = dw_dma_block2bytes;
+
+ /* Device operations */
+ dw->set_device_name = dw_dma_set_device_name;
+ dw->disable = dw_dma_disable;
+ dw->enable = dw_dma_enable;
+
+ chip->dw = dw;
+ return do_dma_probe(chip);
+}
+EXPORT_SYMBOL_GPL(dw_dma_probe);
+
+int dw_dma_remove(struct dw_dma_chip *chip)
+{
+ return do_dma_remove(chip);
+}
+EXPORT_SYMBOL_GPL(dw_dma_remove);