[PATCH v2 2/2] lib: utils/sys: Extend HTIF library to allow custom base address
Atish Patra
atishp at atishpatra.org
Mon Jan 10 14:31:17 PST 2022
On Sun, Jan 9, 2022 at 7:20 AM Anup Patel <apatel at ventanamicro.com> wrote:
>
> Some of RISC-V emulators provide HTIF at fixed base address so for
> such emulators users have to hard-code HTIF base address in the
> linker script.
>
> To address this problem, we let users optionally provide fixed HTIF
> base address via platform support (or device tree).
>
> Signed-off-by: Anup Patel <apatel at ventanamicro.com>
> Reviewed-by: Dong Du <Dd_nirvana at sjtu.edu.cn>
> ---
> include/sbi_utils/sys/htif.h | 8 ++-
> lib/utils/reset/fdt_reset_htif.c | 12 ++++-
> lib/utils/serial/fdt_serial_htif.c | 12 ++++-
> lib/utils/sys/htif.c | 85 ++++++++++++++++++++++++++----
> 4 files changed, 103 insertions(+), 14 deletions(-)
>
> diff --git a/include/sbi_utils/sys/htif.h b/include/sbi_utils/sys/htif.h
> index 9cc9634..78784cf 100644
> --- a/include/sbi_utils/sys/htif.h
> +++ b/include/sbi_utils/sys/htif.h
> @@ -10,8 +10,12 @@
>
> #include <sbi/sbi_types.h>
>
> -int htif_serial_init(void);
> +int htif_serial_init(bool custom_addr,
> + unsigned long custom_fromhost_addr,
> + unsigned long custom_tohost_addr);
>
> -int htif_system_reset_init(void);
> +int htif_system_reset_init(bool custom_addr,
> + unsigned long custom_fromhost_addr,
> + unsigned long custom_tohost_addr);
>
> #endif
> diff --git a/lib/utils/reset/fdt_reset_htif.c b/lib/utils/reset/fdt_reset_htif.c
> index dd08660..2cc52dd 100644
> --- a/lib/utils/reset/fdt_reset_htif.c
> +++ b/lib/utils/reset/fdt_reset_htif.c
> @@ -14,7 +14,17 @@
> static int htif_reset_init(void *fdt, int nodeoff,
> const struct fdt_match *match)
> {
> - return htif_system_reset_init();
> + bool custom = false;
> + uint64_t fromhost_addr = 0, tohost_addr = 0;
> +
> + if (!fdt_get_node_addr_size(fdt, nodeoff, 0, &fromhost_addr, NULL)) {
> + custom = true;
> + tohost_addr = fromhost_addr + sizeof(uint64_t);
> + }
> +
> + fdt_get_node_addr_size(fdt, nodeoff, 1, &tohost_addr, NULL);
> +
> + return htif_system_reset_init(custom, fromhost_addr, tohost_addr);
> }
>
> static const struct fdt_match htif_reset_match[] = {
> diff --git a/lib/utils/serial/fdt_serial_htif.c b/lib/utils/serial/fdt_serial_htif.c
> index fae55b8..61f66d6 100644
> --- a/lib/utils/serial/fdt_serial_htif.c
> +++ b/lib/utils/serial/fdt_serial_htif.c
> @@ -19,7 +19,17 @@ static const struct fdt_match serial_htif_match[] = {
> static int serial_htif_init(void *fdt, int nodeoff,
> const struct fdt_match *match)
> {
> - return htif_serial_init();
> + bool custom = false;
> + uint64_t fromhost_addr = 0, tohost_addr = 0;
> +
> + if (!fdt_get_node_addr_size(fdt, nodeoff, 0, &fromhost_addr, NULL)) {
> + custom = true;
> + tohost_addr = fromhost_addr + sizeof(uint64_t);
> + }
> +
> + fdt_get_node_addr_size(fdt, nodeoff, 1, &tohost_addr, NULL);
> +
> + return htif_serial_init(custom, fromhost_addr, tohost_addr);
> }
>
> struct fdt_serial fdt_serial_htif = {
> diff --git a/lib/utils/sys/htif.c b/lib/utils/sys/htif.c
> index 7c69c7f..d7cbeaf 100644
> --- a/lib/utils/sys/htif.c
> +++ b/lib/utils/sys/htif.c
> @@ -7,6 +7,7 @@
>
> #include <sbi/riscv_locks.h>
> #include <sbi/sbi_console.h>
> +#include <sbi/sbi_error.h>
> #include <sbi/sbi_system.h>
> #include <sbi_utils/sys/htif.h>
>
> @@ -47,15 +48,46 @@
>
> volatile uint64_t tohost __attribute__((section(".htif")));
> volatile uint64_t fromhost __attribute__((section(".htif")));
> +
> +static uint64_t *htif_fromhost = NULL;
> +static uint64_t *htif_tohost = NULL;
> +static bool htif_custom = false;
> +
> static int htif_console_buf;
> static spinlock_t htif_lock = SPIN_LOCK_INITIALIZER;
>
> +static inline uint64_t __read_tohost(void)
> +{
> + return (htif_custom) ? *htif_tohost : tohost;
> +}
> +
> +static inline void __write_tohost(uint64_t val)
> +{
> + if (htif_custom)
> + *htif_tohost = val;
> + else
> + tohost = val;
> +}
> +
> +static inline uint64_t __read_fromhost(void)
> +{
> + return (htif_custom) ? *htif_fromhost : fromhost;
> +}
> +
> +static inline void __write_fromhost(uint64_t val)
> +{
> + if (htif_custom)
> + *htif_fromhost = val;
> + else
> + fromhost = val;
> +}
> +
> static void __check_fromhost()
> {
> - uint64_t fh = fromhost;
> + uint64_t fh = __read_fromhost();
> if (!fh)
> return;
> - fromhost = 0;
> + __write_fromhost(0);
>
> /* this should be from the console */
> if (FROMHOST_DEV(fh) != HTIF_DEV_CONSOLE)
> @@ -73,9 +105,26 @@ static void __check_fromhost()
>
> static void __set_tohost(uint64_t dev, uint64_t cmd, uint64_t data)
> {
> - while (tohost)
> + while (__read_tohost())
> __check_fromhost();
> - tohost = TOHOST_CMD(dev, cmd, data);
> + __write_tohost(TOHOST_CMD(dev, cmd, data));
> +}
> +
> +static int set_custom_addr(bool custom_addr,
> + unsigned long custom_fromhost_addr,
> + unsigned long custom_tohost_addr)
> +{
> + if (custom_addr) {
> + if (htif_custom &&
> + ((custom_fromhost_addr != (unsigned long)htif_fromhost) ||
> + (custom_tohost_addr != (unsigned long)htif_tohost)))
> + return SBI_EINVAL;
> + htif_fromhost = (uint64_t *)custom_fromhost_addr;
> + htif_tohost = (uint64_t *)custom_tohost_addr;
> + htif_custom = true;
> + }
> +
> + return 0;
> }
>
> #if __riscv_xlen == 32
> @@ -148,10 +197,18 @@ static struct sbi_console_device htif_console = {
> .console_getc = htif_getc
> };
>
> -int htif_serial_init(void)
> +int htif_serial_init(bool custom_addr,
> + unsigned long custom_fromhost_addr,
> + unsigned long custom_tohost_addr)
> {
> - sbi_console_set_device(&htif_console);
> + int rc;
> +
> + rc = set_custom_addr(custom_addr, custom_fromhost_addr,
> + custom_tohost_addr);
> + if (rc)
> + return rc;
>
> + sbi_console_set_device(&htif_console);
> return 0;
> }
>
> @@ -163,8 +220,8 @@ static int htif_system_reset_check(u32 type, u32 reason)
> static void htif_system_reset(u32 type, u32 reason)
> {
> while (1) {
> - fromhost = 0;
> - tohost = 1;
> + __write_fromhost(0);
> + __write_tohost(1);
> }
> }
>
> @@ -174,9 +231,17 @@ static struct sbi_system_reset_device htif_reset = {
> .system_reset = htif_system_reset
> };
>
> -int htif_system_reset_init(void)
> +int htif_system_reset_init(bool custom_addr,
> + unsigned long custom_fromhost_addr,
> + unsigned long custom_tohost_addr)
> {
> - sbi_system_reset_add_device(&htif_reset);
> + int rc;
> +
> + rc = set_custom_addr(custom_addr, custom_fromhost_addr,
> + custom_tohost_addr);
> + if (rc)
> + return rc;
>
> + sbi_system_reset_add_device(&htif_reset);
> return 0;
> }
> --
> 2.25.1
>
Reviewed-by: Atish Patra <atishp at rivosinc.com>
--
Regards,
Atish
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