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-rw-r--r--drivers/dma/hsu/pci.c144
1 files changed, 144 insertions, 0 deletions
diff --git a/drivers/dma/hsu/pci.c b/drivers/dma/hsu/pci.c
new file mode 100644
index 000000000..9045a6f7f
--- /dev/null
+++ b/drivers/dma/hsu/pci.c
@@ -0,0 +1,144 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * PCI driver for the High Speed UART DMA
+ *
+ * Copyright (C) 2015 Intel Corporation
+ * Author: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
+ *
+ * Partially based on the bits found in drivers/tty/serial/mfd.c.
+ */
+
+#include <linux/bitops.h>
+#include <linux/device.h>
+#include <linux/module.h>
+#include <linux/pci.h>
+
+#include "hsu.h"
+
+#define HSU_PCI_DMASR 0x00
+#define HSU_PCI_DMAISR 0x04
+
+#define HSU_PCI_CHAN_OFFSET 0x100
+
+#define PCI_DEVICE_ID_INTEL_MFLD_HSU_DMA 0x081e
+#define PCI_DEVICE_ID_INTEL_MRFLD_HSU_DMA 0x1192
+
+static irqreturn_t hsu_pci_irq(int irq, void *dev)
+{
+ struct hsu_dma_chip *chip = dev;
+ u32 dmaisr;
+ u32 status;
+ unsigned short i;
+ int ret = 0;
+ int err;
+
+ dmaisr = readl(chip->regs + HSU_PCI_DMAISR);
+ for (i = 0; i < chip->hsu->nr_channels; i++) {
+ if (dmaisr & 0x1) {
+ err = hsu_dma_get_status(chip, i, &status);
+ if (err > 0)
+ ret |= 1;
+ else if (err == 0)
+ ret |= hsu_dma_do_irq(chip, i, status);
+ }
+ dmaisr >>= 1;
+ }
+
+ return IRQ_RETVAL(ret);
+}
+
+static int hsu_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
+{
+ struct hsu_dma_chip *chip;
+ int ret;
+
+ ret = pcim_enable_device(pdev);
+ if (ret)
+ return ret;
+
+ ret = pcim_iomap_regions(pdev, BIT(0), pci_name(pdev));
+ if (ret) {
+ dev_err(&pdev->dev, "I/O memory remapping failed\n");
+ return ret;
+ }
+
+ pci_set_master(pdev);
+ pci_try_set_mwi(pdev);
+
+ ret = pci_set_dma_mask(pdev, DMA_BIT_MASK(32));
+ if (ret)
+ return ret;
+
+ ret = pci_set_consistent_dma_mask(pdev, DMA_BIT_MASK(32));
+ if (ret)
+ return ret;
+
+ chip = devm_kzalloc(&pdev->dev, sizeof(*chip), GFP_KERNEL);
+ if (!chip)
+ return -ENOMEM;
+
+ ret = pci_alloc_irq_vectors(pdev, 1, 1, PCI_IRQ_ALL_TYPES);
+ if (ret < 0)
+ return ret;
+
+ chip->dev = &pdev->dev;
+ chip->regs = pcim_iomap_table(pdev)[0];
+ chip->length = pci_resource_len(pdev, 0);
+ chip->offset = HSU_PCI_CHAN_OFFSET;
+ chip->irq = pci_irq_vector(pdev, 0);
+
+ ret = hsu_dma_probe(chip);
+ if (ret)
+ return ret;
+
+ ret = request_irq(chip->irq, hsu_pci_irq, 0, "hsu_dma_pci", chip);
+ if (ret)
+ goto err_register_irq;
+
+ /*
+ * On Intel Tangier B0 and Anniedale the interrupt line, disregarding
+ * to have different numbers, is shared between HSU DMA and UART IPs.
+ * Thus on such SoCs we are expecting that IRQ handler is called in
+ * UART driver only. Instead of handling the spurious interrupt
+ * from HSU DMA here and waste CPU time and delay HSU UART interrupt
+ * handling, disable the interrupt entirely.
+ */
+ if (pdev->device == PCI_DEVICE_ID_INTEL_MRFLD_HSU_DMA)
+ disable_irq_nosync(chip->irq);
+
+ pci_set_drvdata(pdev, chip);
+
+ return 0;
+
+err_register_irq:
+ hsu_dma_remove(chip);
+ return ret;
+}
+
+static void hsu_pci_remove(struct pci_dev *pdev)
+{
+ struct hsu_dma_chip *chip = pci_get_drvdata(pdev);
+
+ free_irq(chip->irq, chip);
+ hsu_dma_remove(chip);
+}
+
+static const struct pci_device_id hsu_pci_id_table[] = {
+ { PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_MFLD_HSU_DMA), 0 },
+ { PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_MRFLD_HSU_DMA), 0 },
+ { }
+};
+MODULE_DEVICE_TABLE(pci, hsu_pci_id_table);
+
+static struct pci_driver hsu_pci_driver = {
+ .name = "hsu_dma_pci",
+ .id_table = hsu_pci_id_table,
+ .probe = hsu_pci_probe,
+ .remove = hsu_pci_remove,
+};
+
+module_pci_driver(hsu_pci_driver);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("High Speed UART DMA PCI driver");
+MODULE_AUTHOR("Andy Shevchenko <andriy.shevchenko@linux.intel.com>");