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-rw-r--r--drivers/dma/dw/Makefile6
-rw-r--r--drivers/dma/dw/acpi.c2
-rw-r--r--drivers/dma/dw/core.c48
-rw-r--r--drivers/dma/dw/of.c5
-rw-r--r--drivers/dma/dw/pci.c4
-rw-r--r--drivers/dma/dw/regs.h3
6 files changed, 64 insertions, 4 deletions
diff --git a/drivers/dma/dw/Makefile b/drivers/dma/dw/Makefile
index b6f06699e91a..a6f358ad8591 100644
--- a/drivers/dma/dw/Makefile
+++ b/drivers/dma/dw/Makefile
@@ -1,11 +1,11 @@
# SPDX-License-Identifier: GPL-2.0
obj-$(CONFIG_DW_DMAC_CORE) += dw_dmac_core.o
-dw_dmac_core-objs := core.o dw.o idma32.o
+dw_dmac_core-y := core.o dw.o idma32.o
+dw_dmac_core-$(CONFIG_ACPI) += acpi.o
obj-$(CONFIG_DW_DMAC) += dw_dmac.o
dw_dmac-y := platform.o
-dw_dmac-$(CONFIG_ACPI) += acpi.o
dw_dmac-$(CONFIG_OF) += of.o
obj-$(CONFIG_DW_DMAC_PCI) += dw_dmac_pci.o
-dw_dmac_pci-objs := pci.o
+dw_dmac_pci-y := pci.o
diff --git a/drivers/dma/dw/acpi.c b/drivers/dma/dw/acpi.c
index f6e8d55b4f6e..c510c109d2c3 100644
--- a/drivers/dma/dw/acpi.c
+++ b/drivers/dma/dw/acpi.c
@@ -41,6 +41,7 @@ void dw_dma_acpi_controller_register(struct dw_dma *dw)
if (ret)
dev_err(dev, "could not register acpi_dma_controller\n");
}
+EXPORT_SYMBOL_GPL(dw_dma_acpi_controller_register);
void dw_dma_acpi_controller_free(struct dw_dma *dw)
{
@@ -51,3 +52,4 @@ void dw_dma_acpi_controller_free(struct dw_dma *dw)
acpi_dma_controller_free(dev);
}
+EXPORT_SYMBOL_GPL(dw_dma_acpi_controller_free);
diff --git a/drivers/dma/dw/core.c b/drivers/dma/dw/core.c
index a1b56f52db2f..4700f2e87a62 100644
--- a/drivers/dma/dw/core.c
+++ b/drivers/dma/dw/core.c
@@ -786,6 +786,11 @@ static int dwc_config(struct dma_chan *chan, struct dma_slave_config *sconfig)
memcpy(&dwc->dma_sconfig, sconfig, sizeof(*sconfig));
+ dwc->dma_sconfig.src_maxburst =
+ clamp(dwc->dma_sconfig.src_maxburst, 0U, dwc->max_burst);
+ dwc->dma_sconfig.dst_maxburst =
+ clamp(dwc->dma_sconfig.dst_maxburst, 0U, dwc->max_burst);
+
dw->encode_maxburst(dwc, &dwc->dma_sconfig.src_maxburst);
dw->encode_maxburst(dwc, &dwc->dma_sconfig.dst_maxburst);
@@ -1037,6 +1042,25 @@ static void dwc_free_chan_resources(struct dma_chan *chan)
dev_vdbg(chan2dev(chan), "%s: done\n", __func__);
}
+static void dwc_caps(struct dma_chan *chan, struct dma_slave_caps *caps)
+{
+ struct dw_dma_chan *dwc = to_dw_dma_chan(chan);
+
+ caps->max_burst = dwc->max_burst;
+
+ /*
+ * It might be crucial for some devices to have the hardware
+ * accelerated multi-block transfers supported, aka LLPs in DW DMAC
+ * notation. So if LLPs are supported then max_sg_burst is set to
+ * zero which means unlimited number of SG entries can be handled in a
+ * single DMA transaction, otherwise it's just one SG entry.
+ */
+ if (dwc->nollp)
+ caps->max_sg_burst = 1;
+ else
+ caps->max_sg_burst = 0;
+}
+
int do_dma_probe(struct dw_dma_chip *chip)
{
struct dw_dma *dw = chip->dw;
@@ -1166,11 +1190,23 @@ int do_dma_probe(struct dw_dma_chip *chip)
*/
dwc->block_size =
(4 << ((pdata->block_size >> 4 * i) & 0xf)) - 1;
+
+ /*
+ * According to the DW DMA databook the true scatter-
+ * gether LLPs aren't available if either multi-block
+ * config is disabled (CHx_MULTI_BLK_EN == 0) or the
+ * LLP register is hard-coded to zeros
+ * (CHx_HC_LLP == 1).
+ */
dwc->nollp =
- (dwc_params >> DWC_PARAMS_MBLK_EN & 0x1) == 0;
+ (dwc_params >> DWC_PARAMS_MBLK_EN & 0x1) == 0 ||
+ (dwc_params >> DWC_PARAMS_HC_LLP & 0x1) == 1;
+ dwc->max_burst =
+ (0x4 << (dwc_params >> DWC_PARAMS_MSIZE & 0x7));
} else {
dwc->block_size = pdata->block_size;
dwc->nollp = !pdata->multi_block[i];
+ dwc->max_burst = pdata->max_burst[i] ?: DW_DMA_MAX_BURST;
}
}
@@ -1193,6 +1229,7 @@ int do_dma_probe(struct dw_dma_chip *chip)
dw->dma.device_prep_dma_memcpy = dwc_prep_dma_memcpy;
dw->dma.device_prep_slave_sg = dwc_prep_slave_sg;
+ dw->dma.device_caps = dwc_caps;
dw->dma.device_config = dwc_config;
dw->dma.device_pause = dwc_pause;
dw->dma.device_resume = dwc_resume;
@@ -1202,12 +1239,21 @@ int do_dma_probe(struct dw_dma_chip *chip)
dw->dma.device_issue_pending = dwc_issue_pending;
/* DMA capabilities */
+ dw->dma.min_burst = DW_DMA_MIN_BURST;
+ dw->dma.max_burst = DW_DMA_MAX_BURST;
dw->dma.src_addr_widths = DW_DMA_BUSWIDTHS;
dw->dma.dst_addr_widths = DW_DMA_BUSWIDTHS;
dw->dma.directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV) |
BIT(DMA_MEM_TO_MEM);
dw->dma.residue_granularity = DMA_RESIDUE_GRANULARITY_BURST;
+ /*
+ * For now there is no hardware with non uniform maximum block size
+ * across all of the device channels, so we set the maximum segment
+ * size as the block size found for the very first channel.
+ */
+ dma_set_max_seg_size(dw->dma.dev, dw->chan[0].block_size);
+
err = dma_async_device_register(&dw->dma);
if (err)
goto err_dma_register;
diff --git a/drivers/dma/dw/of.c b/drivers/dma/dw/of.c
index 9e27831dee32..1474b3817ef4 100644
--- a/drivers/dma/dw/of.c
+++ b/drivers/dma/dw/of.c
@@ -98,6 +98,11 @@ struct dw_dma_platform_data *dw_dma_parse_dt(struct platform_device *pdev)
pdata->multi_block[tmp] = 1;
}
+ if (of_property_read_u32_array(np, "snps,max-burst-len", pdata->max_burst,
+ nr_channels)) {
+ memset32(pdata->max_burst, DW_DMA_MAX_BURST, nr_channels);
+ }
+
if (!of_property_read_u32(np, "snps,dma-protection-control", &tmp)) {
if (tmp > CHAN_PROTCTL_MASK)
return NULL;
diff --git a/drivers/dma/dw/pci.c b/drivers/dma/dw/pci.c
index cf6e8ec4c0ff..1142aa6f8c4a 100644
--- a/drivers/dma/dw/pci.c
+++ b/drivers/dma/dw/pci.c
@@ -60,6 +60,8 @@ static int dw_pci_probe(struct pci_dev *pdev, const struct pci_device_id *pid)
if (ret)
return ret;
+ dw_dma_acpi_controller_register(chip->dw);
+
pci_set_drvdata(pdev, data);
return 0;
@@ -71,6 +73,8 @@ static void dw_pci_remove(struct pci_dev *pdev)
struct dw_dma_chip *chip = data->chip;
int ret;
+ dw_dma_acpi_controller_free(chip->dw);
+
ret = data->remove(chip);
if (ret)
dev_warn(&pdev->dev, "can't remove device properly: %d\n", ret);
diff --git a/drivers/dma/dw/regs.h b/drivers/dma/dw/regs.h
index 3fce66ecee7a..76654bd13c1a 100644
--- a/drivers/dma/dw/regs.h
+++ b/drivers/dma/dw/regs.h
@@ -125,6 +125,8 @@ struct dw_dma_regs {
/* Bitfields in DWC_PARAMS */
#define DWC_PARAMS_MBLK_EN 11 /* multi block transfer */
+#define DWC_PARAMS_HC_LLP 13 /* set LLP register to zero */
+#define DWC_PARAMS_MSIZE 16 /* max group transaction size */
/* bursts size */
enum dw_dma_msize {
@@ -283,6 +285,7 @@ struct dw_dma_chan {
/* hardware configuration */
unsigned int block_size;
bool nollp;
+ u32 max_burst;
/* custom slave configuration */
struct dw_dma_slave dws;
generated by cgit v1.2.3 (git 2.39.1) at 2024-05-27 05:46:19 +0000