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Diffstat (limited to 'gitlab/issues/target_riscv/host_missing/accel_missing/2462.toml')
| -rw-r--r-- | gitlab/issues/target_riscv/host_missing/accel_missing/2462.toml | 47 |
1 files changed, 47 insertions, 0 deletions
diff --git a/gitlab/issues/target_riscv/host_missing/accel_missing/2462.toml b/gitlab/issues/target_riscv/host_missing/accel_missing/2462.toml new file mode 100644 index 00000000..8c6bbb4b --- /dev/null +++ b/gitlab/issues/target_riscv/host_missing/accel_missing/2462.toml @@ -0,0 +1,47 @@ +id = 2462 +title = "QEMU SIFIVE reading from stdin hangs" +state = "closed" +created_at = "2024-07-27T13:19:31.620Z" +closed_at = "2024-08-13T02:30:02.602Z" +labels = ["target: riscv"] +url = "https://gitlab.com/qemu-project/qemu/-/issues/2462" +host-os = "Ubuntu23" +host-arch = "x86" +qemu-version = "git from july26, 2024" +guest-os = "n/a" +guest-arch = "n/a" +description = """I have a simple test program (C and ASM) that reads from stdin. When i was using the qemu provided by Ubuntu, QEMU emulator version 8.0.4 (Debian 1:8.0.4+dfsg-1ubuntu3.23.10.5), my test was working, and was able to read bytes from stdin. + +Using the latest Qemu from git, breaks my test. I can still print, but now reading hangs, like its always waiting for input but never getting it. + +My guess is that this commit breaks my code: +https://github.com/qemu/qemu/commit/6ee7ba1b8a10bd8eb1d3b918eaaf9f832a51adb4 + +Before the above commit, `qemu_chr_fe_set_handlers` was being called, and that is what allowed the default behavior of reading from stdin is on by default? + +from sifive_uart.c +``` + qemu_chr_fe_set_handlers(&s->chr, sifive_uart_can_rx, sifive_uart_rx, + sifive_uart_event, sifive_uart_be_change, s, + NULL, true); +```""" +reproduce = """1. compile simple C program that calls `read` reading a single byte from stdin +2. do not initialize UART options +3. run in QEMU, send input, hangs.""" +additional = """Other examples online, like riscv-probe, use a uart init function like below: +``` +static void sifive_uart_init() +{ + uart = (int *)(void *)getauxval(SIFIVE_UART0_CTRL_ADDR); + uint32_t uart_freq = getauxval(UART0_CLOCK_FREQ); + uint32_t baud_rate = getauxval(UART0_BAUD_RATE); + uint32_t divisor = uart_freq / baud_rate - 1; + uart[UART_REG_DIV] = divisor; + uart[UART_REG_TXCTRL] = UART_TXEN; + uart[UART_REG_RXCTRL] = UART_RXEN; + uart[UART_REG_IE] = 0; +} +``` + +However, when I was using QEMU 8.0.4, i did not have to write a function like above to init UART, because stdin and stdout were working out of the box. +Below is my C and ASM:""" |