Loading...
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * PCI driver for the High Speed UART DMA
4 *
5 * Copyright (C) 2015 Intel Corporation
6 * Author: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
7 *
8 * Partially based on the bits found in drivers/tty/serial/mfd.c.
9 */
10
11#include <linux/bitops.h>
12#include <linux/device.h>
13#include <linux/module.h>
14#include <linux/pci.h>
15
16#include "hsu.h"
17
18#define HSU_PCI_DMASR 0x00
19#define HSU_PCI_DMAISR 0x04
20
21#define HSU_PCI_CHAN_OFFSET 0x100
22
23#define PCI_DEVICE_ID_INTEL_MFLD_HSU_DMA 0x081e
24#define PCI_DEVICE_ID_INTEL_MRFLD_HSU_DMA 0x1192
25
26static irqreturn_t hsu_pci_irq(int irq, void *dev)
27{
28 struct hsu_dma_chip *chip = dev;
29 struct pci_dev *pdev = to_pci_dev(chip->dev);
30 u32 dmaisr;
31 u32 status;
32 unsigned short i;
33 int ret = 0;
34 int err;
35
36 /*
37 * On Intel Tangier B0 and Anniedale the interrupt line, disregarding
38 * to have different numbers, is shared between HSU DMA and UART IPs.
39 * Thus on such SoCs we are expecting that IRQ handler is called in
40 * UART driver only.
41 */
42 if (pdev->device == PCI_DEVICE_ID_INTEL_MRFLD_HSU_DMA)
43 return IRQ_HANDLED;
44
45 dmaisr = readl(chip->regs + HSU_PCI_DMAISR);
46 for (i = 0; i < chip->hsu->nr_channels; i++) {
47 if (dmaisr & 0x1) {
48 err = hsu_dma_get_status(chip, i, &status);
49 if (err > 0)
50 ret |= 1;
51 else if (err == 0)
52 ret |= hsu_dma_do_irq(chip, i, status);
53 }
54 dmaisr >>= 1;
55 }
56
57 return IRQ_RETVAL(ret);
58}
59
60static int hsu_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
61{
62 struct hsu_dma_chip *chip;
63 int ret;
64
65 ret = pcim_enable_device(pdev);
66 if (ret)
67 return ret;
68
69 ret = pcim_iomap_regions(pdev, BIT(0), pci_name(pdev));
70 if (ret) {
71 dev_err(&pdev->dev, "I/O memory remapping failed\n");
72 return ret;
73 }
74
75 pci_set_master(pdev);
76 pci_try_set_mwi(pdev);
77
78 ret = pci_set_dma_mask(pdev, DMA_BIT_MASK(32));
79 if (ret)
80 return ret;
81
82 ret = pci_set_consistent_dma_mask(pdev, DMA_BIT_MASK(32));
83 if (ret)
84 return ret;
85
86 chip = devm_kzalloc(&pdev->dev, sizeof(*chip), GFP_KERNEL);
87 if (!chip)
88 return -ENOMEM;
89
90 ret = pci_alloc_irq_vectors(pdev, 1, 1, PCI_IRQ_ALL_TYPES);
91 if (ret < 0)
92 return ret;
93
94 chip->dev = &pdev->dev;
95 chip->regs = pcim_iomap_table(pdev)[0];
96 chip->length = pci_resource_len(pdev, 0);
97 chip->offset = HSU_PCI_CHAN_OFFSET;
98 chip->irq = pci_irq_vector(pdev, 0);
99
100 ret = hsu_dma_probe(chip);
101 if (ret)
102 return ret;
103
104 ret = request_irq(chip->irq, hsu_pci_irq, 0, "hsu_dma_pci", chip);
105 if (ret)
106 goto err_register_irq;
107
108 pci_set_drvdata(pdev, chip);
109
110 return 0;
111
112err_register_irq:
113 hsu_dma_remove(chip);
114 return ret;
115}
116
117static void hsu_pci_remove(struct pci_dev *pdev)
118{
119 struct hsu_dma_chip *chip = pci_get_drvdata(pdev);
120
121 free_irq(chip->irq, chip);
122 hsu_dma_remove(chip);
123}
124
125static const struct pci_device_id hsu_pci_id_table[] = {
126 { PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_MFLD_HSU_DMA), 0 },
127 { PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_MRFLD_HSU_DMA), 0 },
128 { }
129};
130MODULE_DEVICE_TABLE(pci, hsu_pci_id_table);
131
132static struct pci_driver hsu_pci_driver = {
133 .name = "hsu_dma_pci",
134 .id_table = hsu_pci_id_table,
135 .probe = hsu_pci_probe,
136 .remove = hsu_pci_remove,
137};
138
139module_pci_driver(hsu_pci_driver);
140
141MODULE_LICENSE("GPL v2");
142MODULE_DESCRIPTION("High Speed UART DMA PCI driver");
143MODULE_AUTHOR("Andy Shevchenko <andriy.shevchenko@linux.intel.com>");
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * PCI driver for the High Speed UART DMA
4 *
5 * Copyright (C) 2015 Intel Corporation
6 * Author: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
7 *
8 * Partially based on the bits found in drivers/tty/serial/mfd.c.
9 */
10
11#include <linux/bitops.h>
12#include <linux/device.h>
13#include <linux/interrupt.h>
14#include <linux/module.h>
15#include <linux/pci.h>
16
17#include "hsu.h"
18
19#define HSU_PCI_DMASR 0x00
20#define HSU_PCI_DMAISR 0x04
21
22#define HSU_PCI_CHAN_OFFSET 0x100
23
24#define PCI_DEVICE_ID_INTEL_MFLD_HSU_DMA 0x081e
25#define PCI_DEVICE_ID_INTEL_MRFLD_HSU_DMA 0x1192
26
27static irqreturn_t hsu_pci_irq(int irq, void *dev)
28{
29 struct hsu_dma_chip *chip = dev;
30 unsigned long dmaisr;
31 unsigned short i;
32 u32 status;
33 int ret = 0;
34 int err;
35
36 dmaisr = readl(chip->regs + HSU_PCI_DMAISR);
37 for_each_set_bit(i, &dmaisr, chip->hsu->nr_channels) {
38 err = hsu_dma_get_status(chip, i, &status);
39 if (err > 0)
40 ret |= 1;
41 else if (err == 0)
42 ret |= hsu_dma_do_irq(chip, i, status);
43 }
44
45 return IRQ_RETVAL(ret);
46}
47
48static void hsu_pci_dma_remove(void *chip)
49{
50 hsu_dma_remove(chip);
51}
52
53static int hsu_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
54{
55 struct device *dev = &pdev->dev;
56 struct hsu_dma_chip *chip;
57 int ret;
58
59 ret = pcim_enable_device(pdev);
60 if (ret)
61 return ret;
62
63 ret = pcim_iomap_regions(pdev, BIT(0), pci_name(pdev));
64 if (ret) {
65 dev_err(&pdev->dev, "I/O memory remapping failed\n");
66 return ret;
67 }
68
69 pci_set_master(pdev);
70 pci_try_set_mwi(pdev);
71
72 ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
73 if (ret)
74 return ret;
75
76 chip = devm_kzalloc(&pdev->dev, sizeof(*chip), GFP_KERNEL);
77 if (!chip)
78 return -ENOMEM;
79
80 ret = pci_alloc_irq_vectors(pdev, 1, 1, PCI_IRQ_ALL_TYPES);
81 if (ret < 0)
82 return ret;
83
84 chip->dev = &pdev->dev;
85 chip->regs = pcim_iomap_table(pdev)[0];
86 chip->length = pci_resource_len(pdev, 0);
87 chip->offset = HSU_PCI_CHAN_OFFSET;
88 chip->irq = pci_irq_vector(pdev, 0);
89
90 ret = hsu_dma_probe(chip);
91 if (ret)
92 return ret;
93
94 ret = devm_add_action_or_reset(dev, hsu_pci_dma_remove, chip);
95 if (ret)
96 return ret;
97
98 ret = devm_request_irq(dev, chip->irq, hsu_pci_irq, 0, "hsu_dma_pci", chip);
99 if (ret)
100 return ret;
101
102 /*
103 * On Intel Tangier B0 and Anniedale the interrupt line, disregarding
104 * to have different numbers, is shared between HSU DMA and UART IPs.
105 * Thus on such SoCs we are expecting that IRQ handler is called in
106 * UART driver only. Instead of handling the spurious interrupt
107 * from HSU DMA here and waste CPU time and delay HSU UART interrupt
108 * handling, disable the interrupt entirely.
109 */
110 if (pdev->device == PCI_DEVICE_ID_INTEL_MRFLD_HSU_DMA)
111 disable_irq_nosync(chip->irq);
112
113 pci_set_drvdata(pdev, chip);
114
115 return 0;
116}
117
118static const struct pci_device_id hsu_pci_id_table[] = {
119 { PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_MFLD_HSU_DMA), 0 },
120 { PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_MRFLD_HSU_DMA), 0 },
121 { }
122};
123MODULE_DEVICE_TABLE(pci, hsu_pci_id_table);
124
125static struct pci_driver hsu_pci_driver = {
126 .name = "hsu_dma_pci",
127 .id_table = hsu_pci_id_table,
128 .probe = hsu_pci_probe,
129};
130
131module_pci_driver(hsu_pci_driver);
132
133MODULE_LICENSE("GPL v2");
134MODULE_DESCRIPTION("High Speed UART DMA PCI driver");
135MODULE_AUTHOR("Andy Shevchenko <andriy.shevchenko@linux.intel.com>");