On 21 December 2015 at 18:19, Andy Shevchenko <andy.shevchenko@xxxxxxxxx> wrote:
> On Mon, Dec 21, 2015 at 6:41 PM, Aleksey Makarov
> <aleksey.makarov@xxxxxxxxxx> wrote:
>> From: Graeme Gregory <graeme.gregory@xxxxxxxxxx>
>>
>> On ARM64 some devices use the AMBA device and not the platform bus for
>> probing so add support for this. Uses a dummy clock for apb_pclk as ACPI
>> does not have a suitable clock representation and to keep the core
>> AMBA bus code unchanged between probing methods.
>>
>> Signed-off-by: Graeme Gregory <graeme.gregory@xxxxxxxxxx>
>> Signed-off-by: Aleksey Makarov <aleksey.makarov@xxxxxxxxxx>
>> ---
>> drivers/acpi/Makefile | 1 +
>> drivers/acpi/acpi_amba.c | 149 +++++++++++++++++++++++++++++++++++++++++++++++
>> drivers/acpi/internal.h | 5 ++
>> 3 files changed, 155 insertions(+)
>> create mode 100644 drivers/acpi/acpi_amba.c
>>
>> diff --git a/drivers/acpi/Makefile b/drivers/acpi/Makefile
>> index 675eaf3..3cf732f 100644
>> --- a/drivers/acpi/Makefile
>> +++ b/drivers/acpi/Makefile
>> @@ -43,6 +43,7 @@ acpi-y += pci_root.o pci_link.o pci_irq.o
>> acpi-y += acpi_lpss.o acpi_apd.o
>> acpi-y += acpi_platform.o
>> acpi-y += acpi_pnp.o
>> +acpi-$(CONFIG_ARM_AMBA) += acpi_amba.o
>> acpi-y += int340x_thermal.o
>> acpi-y += power.o
>> acpi-y += event.o
>> diff --git a/drivers/acpi/acpi_amba.c b/drivers/acpi/acpi_amba.c
>> new file mode 100644
>> index 0000000..ebc8913
>> --- /dev/null
>> +++ b/drivers/acpi/acpi_amba.c
>> @@ -0,0 +1,149 @@
>> +
>> +/*
>> + * ACPI support for platform bus type.
>> + *
>> + * Copyright (C) 2015, Linaro Ltd
>> + * Authors: Graeme Gregory <graeme.gregory@xxxxxxxxxx>
>> + *
>> + * This program is free software; you can redistribute it and/or modify
>> + * it under the terms of the GNU General Public License version 2 as
>> + * published by the Free Software Foundation.
>> + */
>> +
>> +#include <linux/acpi.h>
>> +#include <linux/amba/bus.h>
>> +#include <linux/clkdev.h>
>> +#include <linux/clk-provider.h>
>> +#include <linux/device.h>
>> +#include <linux/err.h>
>> +#include <linux/ioport.h>
>> +#include <linux/kernel.h>
>> +#include <linux/module.h>
>> +
>> +#include "internal.h"
>> +
>> +static const struct acpi_device_id amba_id_list[] = {
>> + {"ARMH0011", 0}, /* PL011 SBSA Uart */
>> + {"ARMH0061", 0}, /* PL061 GPIO Device */
>> + {"", 0},
>> +};
>> +
>> +static struct clk *amba_dummy_clk;
>> +
>> +static void amba_register_dummy_clk(void)
>> +{
>> + struct clk *clk;
>> +
>> + /* If clock already registered */
>> + if (amba_dummy_clk)
>> + return;
>> +
>> + clk = clk_register_fixed_rate(NULL, "apb_pclk", NULL, CLK_IS_ROOT, 0);
>> + clk_register_clkdev(clk, "apb_pclk", NULL);
>> +
>> + amba_dummy_clk = clk;
>> +}
>> +
>> +static int amba_handler_attach(struct acpi_device *adev,
>> + const struct acpi_device_id *id)
>> +{
>> + struct amba_device *dev = NULL;
>> + struct acpi_device *acpi_parent;
>> + struct resource_entry *rentry;
>> + struct list_head resource_list;
>> + struct resource *resources = NULL;
>> + bool address_found = false;
>> + int ret, count, irq_no = 0;
>> +
>> + /* If the ACPI node already has a physical device attached, skip it. */
>> + if (adev->physical_node_count)
>> + return 0;
>> +
>> + amba_register_dummy_clk();
>> +
>> + dev = amba_device_alloc(NULL, 0, 0);
>> + if (!dev) {
>> + pr_err("%s(): amba_device_alloc() failed for %s\n",
>
> Can it be dev_err(&adev->dev, …); ?
> Same for below cases.
>
Yes it probably can, I took the code directly from DT version and
didn't think of using adev->dev directly.
Graeme
>> + __func__, dev_name(&adev->dev));
>> + return 0;
>> + }
>> +
>> + INIT_LIST_HEAD(&resource_list);
>
>> + count = acpi_dev_get_resources(adev, &resource_list, NULL, NULL);
>> + if (count < 0) {
>> + return 0;
>> + } else if (count > 0) {
>> + resources = kmalloc_array(count, sizeof(struct resource),
>> + GFP_KERNEL);
>> + if (!resources) {
>> + acpi_dev_free_resource_list(&resource_list);
>> + return 0;
>> + }
>> + count = 0;
>> + list_for_each_entry(rentry, &resource_list, node) {
>> + switch (resource_type(rentry->res)) {
>> + case IORESOURCE_MEM:
>> + if (!address_found) {
>> + dev->res = *rentry->res;
>> + address_found = true;
>> + }
>> + break;
>> + case IORESOURCE_IRQ:
>> + if (irq_no < AMBA_NR_IRQS)
>> + dev->irq[irq_no++] = rentry->res->start;
>> + break;
>> + default:
>> + dev_warn(&adev->dev, "Invalid resource\n");
>> + }
>> + }
>> + acpi_dev_free_resource_list(&resource_list);
>> + }
>> +
>> + /*
>> + * If the ACPI node has a parent and that parent has a physical device
>> + * attached to it, that physical device should be the parent of the
>> + * platform device we are about to create.
>> + */
>> + dev->dev.parent = NULL;
>> + acpi_parent = adev->parent;
>> + if (acpi_parent) {
>> + struct acpi_device_physical_node *entry;
>> + struct list_head *list;
>> +
>> + mutex_lock(&acpi_parent->physical_node_lock);
>> + list = &acpi_parent->physical_node_list;
>> + if (!list_empty(list)) {
>> + entry = list_first_entry(list,
>> + struct acpi_device_physical_node,
>> + node);
>> + dev->dev.parent = entry->dev;
>> + }
>> + mutex_unlock(&acpi_parent->physical_node_lock);
>> + }
>> +
>> + dev_set_name(&dev->dev, "%s", dev_name(&adev->dev));
>> + ACPI_COMPANION_SET(&dev->dev, adev);
>> +
>> + ret = amba_device_add(dev, &iomem_resource);
>> + if (ret) {
>> + pr_err("%s(): amba_device_add() failed (%d) for %s\n",
>> + __func__, ret, dev_name(&adev->dev));
>> + goto err_free;
>> + }
>> +
>> + return 1;
>> +
>> +err_free:
>> + amba_device_put(dev);
>> + return 0;
>> +}
>> +
>> +static struct acpi_scan_handler amba_handler = {
>> + .ids = amba_id_list,
>> + .attach = amba_handler_attach,
>> +};
>> +
>> +void __init acpi_amba_init(void)
>> +{
>> + acpi_scan_add_handler(&amba_handler);
>> +}
>> diff --git a/drivers/acpi/internal.h b/drivers/acpi/internal.h
>> index 11d87bf..9d58f0c 100644
>> --- a/drivers/acpi/internal.h
>> +++ b/drivers/acpi/internal.h
>> @@ -29,6 +29,11 @@ void acpi_processor_init(void);
>> void acpi_platform_init(void);
>> void acpi_pnp_init(void);
>> void acpi_int340x_thermal_init(void);
>> +#ifdef CONFIG_ARM_AMBA
>> +void acpi_amba_init(void);
>> +#else
>> +static inline void acpi_amba_init(void) {}
>> +#endif
>> int acpi_sysfs_init(void);
>> void acpi_container_init(void);
>> void acpi_memory_hotplug_init(void);
>> --
>> 2.6.4
>>
>> --
>> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
>> the body of a message to majordomo@xxxxxxxxxxxxxxx
>> More majordomo info at http://vger.kernel.org/majordomo-info.html
>> Please read the FAQ at http://www.tux.org/lkml/
>
>
>
> --
> With Best Regards,
> Andy Shevchenko
--
To unsubscribe from this list: send the line "unsubscribe linux-serial" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
