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author | Andrey Makarov <ph.makarov@gmail.com> | 2022-07-16 14:32:10 +0300 |
---|---|---|
committer | Peter Maydell <peter.maydell@linaro.org> | 2022-07-18 13:25:13 +0100 |
commit | 004c8a8bc569c8b18fca6fc90ffe3223daaf17b7 (patch) | |
tree | fb0987e16733a9f93cf7561b9d30c27699096181 /tests | |
parent | 53ae2fdef1f5661cbaa2ea571c517f98e6041cb8 (diff) | |
download | qemu-004c8a8bc569c8b18fca6fc90ffe3223daaf17b7.zip qemu-004c8a8bc569c8b18fca6fc90ffe3223daaf17b7.tar.gz qemu-004c8a8bc569c8b18fca6fc90ffe3223daaf17b7.tar.bz2 |
Align Raspberry Pi DMA interrupts with Linux DTS
There is nothing in the specs on DMA engine interrupt lines: it should have
been in the "BCM2835 ARM Peripherals" datasheet but the appropriate
"ARM peripherals interrupt table" (p.113) is nearly empty.
All Raspberry Pi models 1-3 (based on bcm2835) have
Linux device tree (arch/arm/boot/dts/bcm2835-common.dtsi +25):
/* dma channel 11-14 share one irq */
This information is repeated in the driver code
(drivers/dma/bcm2835-dma.c +1344):
/*
* in case of channel >= 11
* use the 11th interrupt and that is shared
*/
In this patch channels 0--10 and 11--14 are handled separately.
Signed-off-by: Andrey Makarov <andrey.makarov@auriga.com>
Message-id: 20220716113210.349153-1-andrey.makarov@auriga.com
[PMM: fixed checkpatch nits]
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Diffstat (limited to 'tests')
-rw-r--r-- | tests/qtest/bcm2835-dma-test.c | 118 | ||||
-rw-r--r-- | tests/qtest/meson.build | 3 |
2 files changed, 120 insertions, 1 deletions
diff --git a/tests/qtest/bcm2835-dma-test.c b/tests/qtest/bcm2835-dma-test.c new file mode 100644 index 0000000..8293d82 --- /dev/null +++ b/tests/qtest/bcm2835-dma-test.c @@ -0,0 +1,118 @@ +/* + * QTest testcase for BCM283x DMA engine (on Raspberry Pi 3) + * and its interrupts coming to Interrupt Controller. + * + * Copyright (c) 2022 Auriga LLC + * + * SPDX-License-Identifier: GPL-2.0-or-later + */ + +#include "qemu/osdep.h" +#include "libqtest-single.h" + +/* Offsets in raspi3b platform: */ +#define RASPI3_DMA_BASE 0x3f007000 +#define RASPI3_IC_BASE 0x3f00b200 + +/* Used register/fields definitions */ + +/* DMA engine registers: */ +#define BCM2708_DMA_CS 0 +#define BCM2708_DMA_ACTIVE (1 << 0) +#define BCM2708_DMA_INT (1 << 2) + +#define BCM2708_DMA_ADDR 0x04 + +#define BCM2708_DMA_INT_STATUS 0xfe0 + +/* DMA Trasfer Info fields: */ +#define BCM2708_DMA_INT_EN (1 << 0) +#define BCM2708_DMA_D_INC (1 << 4) +#define BCM2708_DMA_S_INC (1 << 8) + +/* Interrupt controller registers: */ +#define IRQ_PENDING_BASIC 0x00 +#define IRQ_GPU_PENDING1_AGGR (1 << 8) +#define IRQ_PENDING_1 0x04 +#define IRQ_ENABLE_1 0x10 + +/* Data for the test: */ +#define SCB_ADDR 256 +#define S_ADDR 32 +#define D_ADDR 64 +#define TXFR_LEN 32 +const uint32_t check_data = 0x12345678; + +static void bcm2835_dma_test_interrupt(int dma_c, int irq_line) +{ + uint64_t dma_base = RASPI3_DMA_BASE + dma_c * 0x100; + int gpu_irq_line = 16 + irq_line; + + /* Check that interrupts are silent by default: */ + writel(RASPI3_IC_BASE + IRQ_ENABLE_1, 1 << gpu_irq_line); + int isr = readl(dma_base + BCM2708_DMA_INT_STATUS); + g_assert_cmpint(isr, ==, 0); + uint32_t reg0 = readl(dma_base + BCM2708_DMA_CS); + g_assert_cmpint(reg0, ==, 0); + uint32_t ic_pending = readl(RASPI3_IC_BASE + IRQ_PENDING_BASIC); + g_assert_cmpint(ic_pending, ==, 0); + uint32_t gpu_pending1 = readl(RASPI3_IC_BASE + IRQ_PENDING_1); + g_assert_cmpint(gpu_pending1, ==, 0); + + /* Prepare Control Block: */ + writel(SCB_ADDR + 0, BCM2708_DMA_S_INC | BCM2708_DMA_D_INC | + BCM2708_DMA_INT_EN); /* transfer info */ + writel(SCB_ADDR + 4, S_ADDR); /* source address */ + writel(SCB_ADDR + 8, D_ADDR); /* destination address */ + writel(SCB_ADDR + 12, TXFR_LEN); /* transfer length */ + writel(dma_base + BCM2708_DMA_ADDR, SCB_ADDR); + + writel(S_ADDR, check_data); + for (int word = S_ADDR + 4; word < S_ADDR + TXFR_LEN; word += 4) { + writel(word, ~check_data); + } + /* Perform the transfer: */ + writel(dma_base + BCM2708_DMA_CS, BCM2708_DMA_ACTIVE); + + /* Check that destination == source: */ + uint32_t data = readl(D_ADDR); + g_assert_cmpint(data, ==, check_data); + for (int word = D_ADDR + 4; word < D_ADDR + TXFR_LEN; word += 4) { + data = readl(word); + g_assert_cmpint(data, ==, ~check_data); + } + + /* Check that interrupt status is set both in DMA and IC controllers: */ + isr = readl(RASPI3_DMA_BASE + BCM2708_DMA_INT_STATUS); + g_assert_cmpint(isr, ==, 1 << dma_c); + + ic_pending = readl(RASPI3_IC_BASE + IRQ_PENDING_BASIC); + g_assert_cmpint(ic_pending, ==, IRQ_GPU_PENDING1_AGGR); + + gpu_pending1 = readl(RASPI3_IC_BASE + IRQ_PENDING_1); + g_assert_cmpint(gpu_pending1, ==, 1 << gpu_irq_line); + + /* Clean up, clear interrupt: */ + writel(dma_base + BCM2708_DMA_CS, BCM2708_DMA_INT); +} + +static void bcm2835_dma_test_interrupts(void) +{ + /* DMA engines 0--10 have separate IRQ lines, 11--14 - only one: */ + bcm2835_dma_test_interrupt(0, 0); + bcm2835_dma_test_interrupt(10, 10); + bcm2835_dma_test_interrupt(11, 11); + bcm2835_dma_test_interrupt(14, 11); +} + +int main(int argc, char **argv) +{ + int ret; + g_test_init(&argc, &argv, NULL); + qtest_add_func("/bcm2835/dma/test_interrupts", + bcm2835_dma_test_interrupts); + qtest_start("-machine raspi3b"); + ret = g_test_run(); + qtest_end(); + return ret; +} diff --git a/tests/qtest/meson.build b/tests/qtest/meson.build index 31287a9..3a47401 100644 --- a/tests/qtest/meson.build +++ b/tests/qtest/meson.build @@ -218,7 +218,8 @@ qtests_aarch64 = \ ['arm-cpu-features', 'numa-test', 'boot-serial-test', - 'migration-test'] + 'migration-test', + 'bcm2835-dma-test'] qtests_s390x = \ (slirp.found() ? ['pxe-test', 'test-netfilter'] : []) + \ |