qemu/tests/qtest/bcm2835-dma-test.c

119 lines
3.7 KiB
C

/*
* 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;
}