Re: [RFC PATCH v4 2/2] tests/qtest: QTest example for RISC-V CSR register

[Thomas Huth]

On 03/07/2024 10.19, Ivan Klokov wrote:
> Added demo for reading CSR register from qtest environment.
>
> Signed-off-by: Ivan Klokov <ivan.klokov@syntacore.com>
> ---
>   tests/qtest/meson.build      |  2 +
>   tests/qtest/riscv-csr-test.c | 86 ++++++++++++++++++++++++++++++++++++
>   2 files changed, 88 insertions(+)
>   create mode 100644 tests/qtest/riscv-csr-test.c
>
> diff --git a/tests/qtest/meson.build b/tests/qtest/meson.build
> index 12792948ff..45d651da99 100644
> --- a/tests/qtest/meson.build
> +++ b/tests/qtest/meson.build
> @@ -259,6 +259,8 @@ qtests_s390x = \
>   qtests_riscv32 = \
>     (config_all_devices.has_key('CONFIG_SIFIVE_E_AON') ? 
> ['sifive-e-aon-watchdog-test'] : [])
>   
> +qtests_riscv32 += ['riscv-csr-test']

Could you please add it directly to the qtests_riscv32 list above intead of 
using a separate += line here?

>   qos_test_ss = ss.source_set()
>   qos_test_ss.add(
>     'ac97-test.c',
> diff --git a/tests/qtest/riscv-csr-test.c b/tests/qtest/riscv-csr-test.c
> new file mode 100644
> index 0000000000..e9af9ca724
> --- /dev/null
> +++ b/tests/qtest/riscv-csr-test.c
> @@ -0,0 +1,86 @@
> +/*
> + * QTest testcase for RISC-V CSRs
> + *
> + * Copyright (c) 2024 Syntacore.
> + *
> + * This program is free software; you can redistribute it and/or modify it
> + * under the terms of the GNU General Public License as published by the
> + * Free Software Foundation; either version 2 of the License, or
> + * (at your option) any later version.
> + *
> + * This program is distributed in the hope that it will be useful, but WITHOUT
> + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
> + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
> + * for more details.
> + */
> +
> +#include "qemu/osdep.h"
> +#include "libqtest-single.h"
> +#include "libqtest.h"
> +
> +static uint64_t qcsr_call(QTestState *qts, const char *name, uint64_t cpu,
> +                           int csrno, uint64_t *val)
> +{
> +    uint64_t res = 0;
> +
> +    res = qtest_csr_call(qts, name, cpu, csrno, val);
> +
> +    return res;
> +}

Could you please get rid of this useless qcsr_call() wrapper and call 
qtest_csr_call() everywhere instead?

> +static int qcsr_get_csr(QTestState *qts, uint64_t cpu,
> +        int csrno, uint64_t *val)

Bad indentation, please align "int csrno" with QTestState.

> +{
> +    int res;
> +
> +    res = qcsr_call(qts, "get_csr", cpu, csrno, val);
> +
> +    return res;
> +}
> +
> +static int qcsr_set_csr(QTestState *qts, uint64_t cpu,
> +        int csrno, uint64_t *val)

dito.

> +{
> +    int res;
> +
> +    res = qcsr_call(qts, "set_csr", cpu, csrno, val);
> +
> +    return res;
> +}
> +
> +static void run_test_csr(void)
> +{
> +

Please remove the empty line above.

> +    uint64_t res;
> +    uint64_t val = 0;
> +
> +    res = qcsr_call(global_qtest, "get_csr", 0, 0xf11, &val);
> +
> +    g_assert_cmpint(res, ==, 0);
> +    g_assert_cmpint(val, ==, 0x100);
> +
> +    val = 0xff;
> +    res = qcsr_call(global_qtest, "set_csr", 0, 0x342, &val);
> +
> +    g_assert_cmpint(res, ==, 0);
> +
> +    val = 0;
> +    res = qcsr_call(global_qtest, "get_csr", 0, 0x342, &val);
> +
> +    g_assert_cmpint(res, ==, 0);
> +    g_assert_cmpint(val, ==, 0xff);
> +
> +    qtest_quit(global_qtest);

Having qtest_quit here, while qtest_start is in the main function, looks 
really ugly and will likely cause trouble when extending the test later.

Please clean it up: Use qts = qtest_init() at the beginning of this function 
instead of calling qtest_start() in main(). Then you can get rid of 
global_qtest completely and also drop the #include "libtest-single.h" 
statement at the beginning of the function.

 Thanks,
  Thomas


> +}
> +
> +int main(int argc, char **argv)
> +{
> +    g_test_init(&argc, &argv, NULL);
> +
> +    qtest_add_func("/cpu/csr", run_test_csr);
> +
> +    qtest_start("-machine virt -cpu any,mvendorid=0x100");
> +
> +    return g_test_run();
> +
> +}