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Move arm to virt armv7, unify arm QEMU and gem5 builds

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gem5 requires armv7, and we learnt that the versatiledb we were using
was pre-v7.

We could have moved to -M vexpress-*, but in the end decided to go for
-M virt due to its simpliciy, and uniformity with aarch64.

platform_device: does not work anymore and was removed, since it was tied
to versatilepb.

We left a mention on the README and removed all in tree source. The QEMU
patch is still left as it was.

As a consequence, the linux tree had no other patches, and we now use
vanilla linux by default, which is a great thing for reproducibility.

Another consequence is the /poweroff.out works for arm -M virt,
and we removed all mentions of the problem.
This commit is contained in:
Ciro Santilli
2018-04-19 21:58:40 +01:00
parent 2852fe1989
commit af210a7671
13 changed files with 206 additions and 3689 deletions
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10
kernel_module/README.adoc
View File

@@ -43,11 +43,11 @@
.. link:virt_to_phys.c[]
. Utilities
.. link:kstrto.c[]
. Misc
.. link:ring0.c[]
. ARM
.. link:pmccntr.c[]
. Arch
.. x86
... link:ring0.c[]
.. ARM
... link:pmccntr.c[]
. Hardware device drivers
.. link:pci_min.c[]
.. link:pci.c[]
.. link:platform_device.c[]

144
kernel_module/platform_device.c
View File

@@ -1,144 +0,0 @@
/*
Only works for ARM.
Uses:
- hw/misc/lkmc_platform_device.c minimal device added in our QEMU fork to `-M versatilepb`
- the device tree entry we added to our Linux kernel fork:
https://github.com/cirosantilli/linux/blob/361bb623671a52a36a077a6dd45843389a687a33/arch/arm/boot/dts/versatile-pb.dts#L42
See: https://stackoverflow.com/questions/28315265/how-to-add-a-new-device-in-qemu-source-code/44612957#44612957
Expected outcome after insmod:
- QEMU reports MMIO with printfs
- IRQs are generated and handled by this module, which logs to dmesg
Also without insmodding this module, try:
devmem 0x101e9000 w 0x12345678
which touches the register from userland through /dev/mem.
*/
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of_address.h>
#include <linux/of_device.h>
#include <linux/of_irq.h>
#include <linux/platform_device.h>
static struct resource res;
static unsigned int irq;
static void __iomem *map;
static irqreturn_t lkmc_irq_handler(int irq, void *dev)
{
/* TODO this 34 and not 18 as in the DTS, likely the interrupt controller moves it around.
* Understand precisely. 34 = 18 + 16, I think 16 is by how much the controller will shift it. */
pr_info("lkmc_irq_handler irq = %d dev = %llx\n", irq, *(unsigned long long *)dev);
/* ACK the IRQ. */
iowrite32(0x9ABCDEF0, map + 4);
return IRQ_HANDLED;
}
static int lkmc_platform_device_probe(struct platform_device *pdev)
{
int asdf;
struct device *dev = &pdev->dev;
struct device_node *np = dev->of_node;
dev_info(dev, "probe\n");
/* Play with our custom device tree poperty. */
if (of_property_read_u32(np, "lkmc-asdf", &asdf) ) {
dev_err(dev, "of_property_read_u32\n");
return -EINVAL;
}
if (asdf != 0x12345678) {
dev_err(dev, "asdf = %llx\n", (unsigned long long)asdf);
return -EINVAL;
}
/* IRQ. Shared so that other test modules may snoop it. */
irq = irq_of_parse_and_map(dev->of_node, 0);
if (request_irq(irq, lkmc_irq_handler, IRQF_SHARED, "lkmc_platform_device", dev) < 0) {
dev_err(dev, "request_irq");
return -EINVAL;
}
dev_info(dev, "irq = %u\n", irq);
/* MMIO. */
if (of_address_to_resource(pdev->dev.of_node, 0, &res)) {
dev_err(dev, "of_address_to_resource");
return -EINVAL;
}
if (!request_mem_region(res.start, resource_size(&res), "lkmc_platform_device")) {
dev_err(dev, "request_mem_region");
return -EINVAL;
}
map = of_iomap(pdev->dev.of_node, 0);
if (!map) {
dev_err(dev, "of_iomap");
return -EINVAL;
}
dev_info(dev, "res.start = %llx resource_size = %llx\n",
(unsigned long long)res.start, (unsigned long long)resource_size(&res));
/* Test MMIO and IRQ: writing to the register generates an IRQ. */
iowrite32(0x12345678, map);
/* Test register read. */
if (ioread32(map + 0) != 0x12340000) panic("assert");
if (ioread32(map + 8) != 0x12340008) panic("assert");
return 0;
}
static int lkmc_platform_device_remove(struct platform_device *pdev)
{
dev_info(&pdev->dev, "remove\n");
free_irq(irq, &pdev->dev);
iounmap(map);
release_mem_region(res.start, resource_size(&res));
return 0;
}
static const struct of_device_id of_lkmc_platform_device_match[] = {
/* This tells our driver which device tree node it will use.
* It matches the kmc_platform_device@XXXX entry that we added to the device tree. */
{ .compatible = "lkmc_platform_device", },
{},
};
MODULE_DEVICE_TABLE(of, of_lkmc_platform_device_match);
static struct platform_driver lkmc_plaform_driver = {
.probe = lkmc_platform_device_probe,
.remove = lkmc_platform_device_remove,
.driver = {
.name = "lkmc_platform_device",
.of_match_table = of_lkmc_platform_device_match,
.owner = THIS_MODULE,
},
};
static int lkmc_platform_device_init(void)
{
pr_info("lkmc_platform_device_init\n");
return platform_driver_register(&lkmc_plaform_driver);
}
static void lkmc_platform_device_exit(void)
{
pr_info("lkmc_platform_device_exit\n");
platform_driver_unregister(&lkmc_plaform_driver);
}
module_init(lkmc_platform_device_init)
module_exit(lkmc_platform_device_exit)
MODULE_LICENSE("GPL");

4
kernel_module/user/README.adoc
View File

@@ -20,7 +20,9 @@ These programs can also be compiled and used on host.
.... link:init_dev_kmsg.c[]
.. link:uio_read.c[]
.. link:rand_check.c[]
.. link:rdtsc.c[]
.. x86_64
... link:rdtsc.c[]
... link:ring0.c[]
. Module tests
.. link:anonymous_inode.c[]
.. link:poll.c[]