Synopsys eDMA IP is normally distributed along with Synopsys PCIe
EndPoint IP (depends of the use and licensing agreement).
This IP requires some basic configurations, such as:
- eDMA registers BAR
- eDMA registers offset
- eDMA linked list BAR
- eDMA linked list offset
- eDMA linked list size
- eDMA version
- eDMA mode
As a working example, PCIe glue-logic will attach to a Synopsys PCIe
EndPoint IP prototype kit (Vendor ID = 0x16c3, Device ID = 0xedda),
which has built-in an eDMA IP with this default configuration:
- eDMA registers BAR = 0
- eDMA registers offset = 0x1000 (4 Kbytes)
- eDMA linked list BAR = 2
- eDMA linked list offset = 0x0 (0 Kbytes)
- eDMA linked list size = 0x20000 (128 Kbytes)
- eDMA version = 0
- eDMA mode = EDMA_MODE_UNROLL
This driver can be compile as built-in or external module in kernel.
To enable this driver just select DW_EDMA_PCIE option in kernel
configuration, however it requires and selects automatically DW_EDMA
option too.
Changes:
RFC v1->RFC v2:
- Replace comments // (C99 style) by /**/
- Merge two pcim_iomap_regions() calls into just one call
- Remove pci_try_set_mwi() call
- Replace some dev_info() by dev_dbg() to reduce *noise*
- Remove pci_name(pdev) call after being call dw_edma_remove()
- Remove all power management support
- Fix the headers of the .c and .h files according to the most recent
convention
- Fix errors and checks pointed out by checkpatch with --strict option
- Replace patch small description tag from dma by dmaengine
Signed-off-by: Gustavo Pimentel <gustavo.pimentel@xxxxxxxxxxxx>
Cc: Vinod Koul <vkoul@xxxxxxxxxx>
Cc: Dan Williams <dan.j.williams@xxxxxxxxx>
Cc: Eugeniy Paltsev <paltsev@xxxxxxxxxxxx>
Cc: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
Cc: Russell King <rmk+kernel@xxxxxxxxxxxxxxx>
Cc: Niklas Cassel <niklas.cassel@xxxxxxxxxx>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@xxxxxxx>
Cc: Joao Pinto <jpinto@xxxxxxxxxxxx>
Cc: Jose Abreu <jose.abreu@xxxxxxxxxxxx>
Cc: Luis Oliveira <lolivei@xxxxxxxxxxxx>
Cc: Vitor Soares <vitor.soares@xxxxxxxxxxxx>
Cc: Nelson Costa <nelson.costa@xxxxxxxxxxxx>
Cc: Pedro Sousa <pedrom.sousa@xxxxxxxxxxxx>
---
drivers/dma/dw-edma/Kconfig | 9 ++
drivers/dma/dw-edma/Makefile | 1 +
drivers/dma/dw-edma/dw-edma-pcie.c | 258 +++++++++++++++++++++++++++++++++++++
3 files changed, 268 insertions(+)
create mode 100644 drivers/dma/dw-edma/dw-edma-pcie.c
diff --git a/drivers/dma/dw-edma/Kconfig b/drivers/dma/dw-edma/Kconfig
index 3016bed..c0838ce 100644
--- a/drivers/dma/dw-edma/Kconfig
+++ b/drivers/dma/dw-edma/Kconfig
@@ -7,3 +7,12 @@ config DW_EDMA
help
Support the Synopsys DesignWare eDMA controller, normally
implemented on endpoints SoCs.
+
+config DW_EDMA_PCIE
+ tristate "Synopsys DesignWare eDMA PCIe driver"
+ depends on PCI && PCI_MSI
+ select DW_EDMA
+ help
+ Provides a glue-logic between the Synopsys DesignWare
+ eDMA controller and an endpoint PCIe device. This also serves
+ as a reference design to whom desires to use this IP.
diff --git a/drivers/dma/dw-edma/Makefile b/drivers/dma/dw-edma/Makefile
index 0c53033..8d45c0d 100644
--- a/drivers/dma/dw-edma/Makefile
+++ b/drivers/dma/dw-edma/Makefile
@@ -4,3 +4,4 @@ obj-$(CONFIG_DW_EDMA) += dw-edma.o
dw-edma-$(CONFIG_DEBUG_FS) := dw-edma-v0-debugfs.o
dw-edma-objs := dw-edma-core.o \
dw-edma-v0-core.o $(dw-edma-y)
+obj-$(CONFIG_DW_EDMA_PCIE) += dw-edma-pcie.o
diff --git a/drivers/dma/dw-edma/dw-edma-pcie.c b/drivers/dma/dw-edma/dw-edma-pcie.c
new file mode 100644
index 0000000..6305768
--- /dev/null
+++ b/drivers/dma/dw-edma/dw-edma-pcie.c
@@ -0,0 +1,258 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2018 Synopsys, Inc. and/or its affiliates.
+ * Synopsys DesignWare eDMA PCIe driver
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/pci.h>
+#include <linux/device.h>
+#include <linux/dma/edma.h>
+
+#include "dw-edma-core.h"
+
+enum dw_edma_pcie_bar {
+ BAR_0,
+ BAR_1,
+ BAR_2,
+ BAR_3,
+ BAR_4,
+ BAR_5
+};
+
+struct dw_edma_pcie_data {
+ enum dw_edma_pcie_bar regs_bar;
+ u64 regs_off;
+ enum dw_edma_pcie_bar ll_bar;
+ u64 ll_off;
+ size_t ll_sz;
+ u32 version;
+ enum dw_edma_mode mode;
+};
+
+static const struct dw_edma_pcie_data snps_edda_data = {
+ /* eDMA registers location */
+ .regs_bar = BAR_0,
+ .regs_off = 0x1000, /* 4 KBytes */
+ /* eDMA memory linked list location */
+ .ll_bar = BAR_2,
+ .ll_off = 0, /* 0 KBytes */
+ .ll_sz = 0x20000, /* 128 KBytes */
+ /* Other */
+ .version = 0,
+ .mode = EDMA_MODE_UNROLL,
+};
+
+static int dw_edma_pcie_probe(struct pci_dev *pdev,
+ const struct pci_device_id *pid)
+{
+ const struct dw_edma_pcie_data *pdata = (void *)pid->driver_data;
+ struct device *dev = &pdev->dev;
+ struct dw_edma_chip *chip;
+ struct dw_edma *dw;
+ void __iomem *reg;
+ int err, irq = -1;
+ u32 addr_hi, addr_lo;
+ u16 flags;
+ u8 cap_off;
+
+ if (!pdata) {
+ dev_err(dev, "%s missing data struture\n",
+ pci_name(pdev));
+ return -EFAULT;
+ }
+
+ err = pcim_enable_device(pdev);
+ if (err) {
+ dev_err(dev, "%s enabling device failed\n",
+ pci_name(pdev));
+ return err;
+ }
+
+ err = pcim_iomap_regions(pdev,
+ BIT(pdata->regs_bar) | BIT(pdata->ll_bar),
+ pci_name(pdev));
+ if (err) {
+ dev_err(dev, "%s eDMA BAR I/O remapping failed\n",
+ pci_name(pdev));
+ return err;
+ }
+
+ pci_set_master(pdev);
+
+ err = pci_set_dma_mask(pdev, DMA_BIT_MASK(32));
+ if (err) {
+ dev_err(dev, "%s DMA mask set failed\n",
+ pci_name(pdev));
+ return err;
+ }
+
+ err = pci_set_consistent_dma_mask(pdev, DMA_BIT_MASK(32));
+ if (err) {
+ dev_err(dev, "%s consistent DMA mask set failed\n",
+ pci_name(pdev));
+ return err;
+ }
+
+ chip = devm_kzalloc(&pdev->dev, sizeof(*chip), GFP_KERNEL);
+ if (!chip)
+ return -ENOMEM;
+
+ dw = devm_kzalloc(&pdev->dev, sizeof(*dw), GFP_KERNEL);
+ if (!dw)
+ return -ENOMEM;
+
+ irq = pci_alloc_irq_vectors(pdev, 1, 1, PCI_IRQ_MSI | PCI_IRQ_MSIX);
+ if (irq < 0) {
+ dev_err(dev, "%s failed to alloc IRQ vector\n",
+ pci_name(pdev));
+ return -EPERM;
+ }
+
+ chip->dw = dw;
+ chip->dev = dev;
+ chip->id = pdev->devfn;
+ chip->irq = pdev->irq;
+
+ dw->regs = pcim_iomap_table(pdev)[pdata->regs_bar];
+ dw->regs += pdata->regs_off;
+
+ dw->va_ll = pcim_iomap_table(pdev)[pdata->ll_bar];
+ dw->va_ll += pdata->ll_off;
+ dw->pa_ll = pdev->resource[pdata->ll_bar].start;
+ dw->pa_ll += pdata->ll_off;
+ dw->ll_sz = pdata->ll_sz;
+
+ dw->msi_addr = 0;
+ dw->msi_data = 0;
+
+ dw->version = pdata->version;
+ dw->mode = pdata->mode;
+
+ dev_dbg(dev, "Version:\t%u\n", dw->version);
+
+ dev_dbg(dev, "Mode:\t%s\n",
+ dw->mode == EDMA_MODE_LEGACY ? "Legacy" : "Unroll");
+
+ dev_dbg(dev, "Registers:\tBAR=%u, off=0x%.16llx B, addr=0x%.8lx\n",
+ pdata->regs_bar, pdata->regs_off,
+ (unsigned long)dw->regs);
+
+ dev_dbg(dev, "L. List:\tBAR=%u, off=0x%.16llx B, sz=0x%.8x B, vaddr=0x%.8lx, paddr=0x%.8lx",
+ pdata->ll_bar, pdata->ll_off, pdata->ll_sz,
+ (unsigned long)dw->va_ll,
+ (unsigned long)dw->pa_ll);
+
+ if (pdev->msi_cap && pdev->msi_enabled) {
+ cap_off = pdev->msi_cap + PCI_MSI_FLAGS;
+ pci_read_config_word(pdev, cap_off, &flags);
+ if (flags & PCI_MSI_FLAGS_ENABLE) {
+ cap_off = pdev->msi_cap + PCI_MSI_ADDRESS_LO;
+ pci_read_config_dword(pdev, cap_off, &addr_lo);
+
+ if (flags & PCI_MSI_FLAGS_64BIT) {
+ cap_off = pdev->msi_cap + PCI_MSI_ADDRESS_HI;
+ pci_read_config_dword(pdev, cap_off, &addr_hi);
+ cap_off = pdev->msi_cap + PCI_MSI_DATA_64;
+ } else {
+ addr_hi = 0;
+ cap_off = pdev->msi_cap + PCI_MSI_DATA_32;
+ }
+
+ dw->msi_addr = addr_hi;
+ dw->msi_addr <<= 32;
+ dw->msi_addr |= addr_lo;
+
+ pci_read_config_dword(pdev, cap_off, &dw->msi_data);
+ dw->msi_data &= 0xffff;
+
+ dev_dbg(dev, "MSI:\t\taddr=0x%.16llx, data=0x%.8x, nr=%d\n",
+ dw->msi_addr, dw->msi_data, pdev->irq);
+ }
+ }
+
+ if (pdev->msix_cap && pdev->msix_enabled) {
+ u32 offset;
+ u8 bir;
+
+ cap_off = pdev->msix_cap + PCI_MSIX_FLAGS;
+ pci_read_config_word(pdev, cap_off, &flags);
+
+ if (flags & PCI_MSIX_FLAGS_ENABLE) {
+ cap_off = pdev->msix_cap + PCI_MSIX_TABLE;
+ pci_read_config_dword(pdev, cap_off, &offset);
+
+ bir = offset & PCI_MSIX_TABLE_BIR;
+ offset &= PCI_MSIX_TABLE_OFFSET;
+
+ reg = pcim_iomap_table(pdev)[bir];
+ reg += offset;
+
+ addr_lo = readl(reg + PCI_MSIX_ENTRY_LOWER_ADDR);
+ addr_hi = readl(reg + PCI_MSIX_ENTRY_UPPER_ADDR);
+ dw->msi_addr = addr_hi;
+ dw->msi_addr <<= 32;
+ dw->msi_addr |= addr_lo;
+
+ dw->msi_data = readl(reg + PCI_MSIX_ENTRY_DATA);
+
+ dev_dbg(dev,
+ "MSI-X:\taddr=0x%.16llx, data=0x%.8x, nr=%d\n",
+ dw->msi_addr, dw->msi_data, pdev->irq);
+ }
+ }
+
+ if (!pdev->msi_enabled && !pdev->msix_enabled) {
+ dev_err(dev, "%s enable interrupt failed\n",
+ pci_name(pdev));
+ return -EPERM;
+ }
+
+ err = dw_edma_probe(chip);
+ if (err) {
+ dev_err(dev, "%s eDMA probe failed\n",
+ pci_name(pdev));
+ return err;
+ }
+
+ pci_set_drvdata(pdev, chip);
+
+ dev_info(dev, "DesignWare eDMA PCIe driver loaded completely\n");
+
+ return 0;
+}
+
+static void dw_edma_pcie_remove(struct pci_dev *pdev)
+{
+ struct dw_edma_chip *chip = pci_get_drvdata(pdev);
+ struct device *dev = &pdev->dev;
+ int err;
+
+ err = dw_edma_remove(chip);
+ if (err)
+ dev_warn(dev, "can't remove device properly: %d\n", err);
+
+ pci_free_irq_vectors(pdev);
+
+ dev_info(dev, "DesignWare eDMA PCIe driver unloaded completely\n");
+}
+
+static const struct pci_device_id dw_edma_pcie_id_table[] = {
+ { PCI_DEVICE_DATA(SYNOPSYS, EDDA, &snps_edda_data) },
+ { }
+};
+MODULE_DEVICE_TABLE(pci, dw_edma_pcie_id_table);
+
+static struct pci_driver dw_edma_pcie_driver = {
+ .name = "dw-edma-pcie",
+ .id_table = dw_edma_pcie_id_table,
+ .probe = dw_edma_pcie_probe,
+ .remove = dw_edma_pcie_remove,
+};
+
+module_pci_driver(dw_edma_pcie_driver);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("Synopsys DesignWare eDMA PCIe driver");
+MODULE_AUTHOR("Gustavo Pimentel <gustavo.pimentel@xxxxxxxxxxxx>");
--
2.7.4
