On 23.01.2018 19:26, Collin L. Walling wrote:
> Implements an sclp_read function to capture input from the
> console and a wrapper function that handles parsing certain
> characters and adding input to a buffer. The input is checked
> for any erroneous values and is handled appropriately.
>
> A prompt will persist until input is entered or the timeout
> expires (if one was set). Example:
>
> Please choose (default will boot in 10 seconds):
Wondering if it would be possible to print the list of boot options
(just like zipl, if that is possible).
>
> Correct input will boot the respective boot index. If the
> user's input is empty, 0, or if the timeout expires, then
> the default zipl entry will be chosen. If the input is
> within the range of available boot entries, then the
> selection will be booted. Any erroneous input will cancel
> the timeout and re-prompt the user.
>
> Signed-off-by: Collin L. Walling <wall...@linux.vnet.ibm.com>
> ---
> pc-bios/s390-ccw/menu.c | 152
> +++++++++++++++++++++++++++++++++++++++++++-
> pc-bios/s390-ccw/s390-ccw.h | 2 +
> pc-bios/s390-ccw/sclp.c | 20 ++++++
> pc-bios/s390-ccw/virtio.c | 2 +-
> 4 files changed, 172 insertions(+), 4 deletions(-)
>
> diff --git a/pc-bios/s390-ccw/menu.c b/pc-bios/s390-ccw/menu.c
> index 174285e..24d4bba 100644
> --- a/pc-bios/s390-ccw/menu.c
> +++ b/pc-bios/s390-ccw/menu.c
> @@ -12,16 +12,162 @@
> #include "menu.h"
> #include "s390-ccw.h"
>
> -static uint8_t flags;
> -static uint64_t timeout;
> +#define KEYCODE_NO_INP '\0'
> +#define KEYCODE_ESCAPE '\033'
> +#define KEYCODE_BACKSP '\177'
> +#define KEYCODE_ENTER '\r'
>
> /* Offsets from zipl fields to zipl banner start */
> #define ZIPL_TIMEOUT_OFFSET 138
> #define ZIPL_FLAG_OFFSET 140
>
> +#define TOD_CLOCK_SECOND 0xf4240000
> +
> +static uint8_t flags;
> +static uint64_t timeout;
> +
> +static inline void enable_clock_int(void)
> +{
> + uint64_t tmp = 0;
Initialization is not necessary. (output only register.)
> +
> + asm volatile(
> + "stctg 0,0,%0\n"
> + "oi 6+%0, 0x8\n"
Isn't the commonly used syntax 6(%0)? (e.g. see consume_sclp_int )
(but then I think you would have to move tmp into an "r" instead).
Definitely not an expert :)
> + "lctlg 0,0,%0"
> + : : "Q" (tmp) : "memory"
> + );
> +}
> +
> +static inline void disable_clock_int(void)
> +{
> + uint64_t tmp = 0;
dito.
Wonder if some stctg/lctlg helpers would be better, than the
anding/oring can be done in c code.
> +
> + asm volatile(
> + "stctg 0,0,%0\n"
> + "ni 6+%0, 0xf7\n"
> + "lctlg 0,0,%0"
> + : : "Q" (tmp) : "memory"
> + );
> +}
> +
> +static inline void set_clock_comparator(uint64_t time)
> +{
> + asm volatile("sckc %0" : : "Q" (time));
> +}
> +
> +static inline bool check_clock_int(void)
> +{
> + uint16_t *code = (uint16_t *)0x86; /* low-core external interrupt code */
> +
> + consume_sclp_int();
Can you add a comment like
/*
* We either receive an sclp interrupt or a timer interrupt.
*/
However, I think this would be much cleaner if refactored into:
consume_sclp_int() -> consume_ext_int().
And move
- the "enable service interrupts in cr0" into a C function
enable_sclp_int()
- the "disable service interrupts in cr0" into a C function
disable_sclp_int()
void consume_sclp_int(void)
{
enable_sclp_int();
consume_ext_int();
disable_sclp_int();
}
For existing code and for your function here e.g.
enable_sclp_int();
enable_clock_comparator_int();
consume_ext_int();
disable_clck_comparator_int();
disable_sclp_int();
return *code == 0x1004;
> +
> + return *code == 0x1004;
> +}
> +
> +static int read_prompt(char *buf, size_t len)
> +{
> + char inp[2] = {};
> + uint8_t idx = 0;
> + uint64_t time;
> +
> + if (timeout) {
> + time = get_clock() + (timeout * TOD_CLOCK_SECOND);
> + set_clock_comparator(time);
> + enable_clock_int();
> + timeout = 0;
> + }
> +
> + while (!check_clock_int()) {
> +
> + /* Process only one character at a time */
> + sclp_read(inp, 1);
> +
> + switch (inp[0]) {
> + case KEYCODE_NO_INP:
> + case KEYCODE_ESCAPE:
> + continue;
> + case KEYCODE_BACKSP:
> + if (idx > 0) {
> + buf[--idx] = 0;
> + sclp_print("\b \b");
> + }
> + continue;
> + case KEYCODE_ENTER:
> + disable_clock_int();
> + return idx;
> + }
> +
> + /* Echo input and add to buffer */
> + if (idx < len) {
> + buf[idx] = inp[0];
> + sclp_print(inp);
> + idx++;
> + }
> + }
> +
> + disable_clock_int();
> + *buf = 0;
> +
> + return 0;
> +}
> +
> +static int get_index(void)
> +{
> + char buf[10];
> + int len;
> + int i;
> +
> + memset(buf, 0, sizeof(buf));
> +
> + len = read_prompt(buf, sizeof(buf));
> +
> + /* If no input, boot default */
> + if (len == 0) {
> + return 0;
> + }
> +
> + /* Check for erroneous input */
> + for (i = 0; i < len; i++) {
> + if (!isdigit(buf[i])) {
> + return -1;
> + }
> + }
> +
> + return atoi(buf);
> +}
> +
> +static void boot_menu_prompt(bool retry)
> +{
> + char tmp[6];
> +
> + if (retry) {
> + sclp_print("\nError: undefined configuration"
> + "\nPlease choose:\n");
> + } else if (timeout > 0) {
> + sclp_print("Please choose (default will boot in ");
> + sclp_print(itostr(timeout, tmp, sizeof(tmp)));
> + sclp_print(" seconds):\n");
> + } else {
> + sclp_print("Please choose:\n");
> + }
> +}
> +
> static int get_boot_index(int entries)
> {
> - return 0; /* Implemented next patch */
> + int boot_index;
> + bool retry = false;
> + char tmp[5];
> +
> + do {
> + boot_menu_prompt(retry);
> + boot_index = get_index();
> + retry = true;
> + } while (boot_index < 0 || boot_index >= entries);
> +
> + sclp_print("\nBooting entry #");
> + sclp_print(itostr(boot_index, tmp, sizeof(tmp)));
> +
> + return boot_index;
> }
>
> static void zipl_println(const char *data, size_t len)
> diff --git a/pc-bios/s390-ccw/s390-ccw.h b/pc-bios/s390-ccw/s390-ccw.h
> index 25d4d21..df4bc88 100644
> --- a/pc-bios/s390-ccw/s390-ccw.h
> +++ b/pc-bios/s390-ccw/s390-ccw.h
> @@ -71,6 +71,7 @@ unsigned int get_loadparm_index(void);
> void sclp_print(const char *string);
> void sclp_setup(void);
> void sclp_get_loadparm_ascii(char *loadparm);
> +void sclp_read(char *str, size_t len);
>
> /* virtio.c */
> unsigned long virtio_load_direct(ulong rec_list1, ulong rec_list2,
> @@ -79,6 +80,7 @@ bool virtio_is_supported(SubChannelId schid);
> void virtio_blk_setup_device(SubChannelId schid);
> int virtio_read(ulong sector, void *load_addr);
> int enable_mss_facility(void);
> +u64 get_clock(void);
> ulong get_second(void);
>
> /* bootmap.c */
> diff --git a/pc-bios/s390-ccw/sclp.c b/pc-bios/s390-ccw/sclp.c
> index 486fce1..5e4a78b 100644
> --- a/pc-bios/s390-ccw/sclp.c
> +++ b/pc-bios/s390-ccw/sclp.c
> @@ -101,3 +101,23 @@ void sclp_get_loadparm_ascii(char *loadparm)
> ebcdic_to_ascii((char *) sccb->loadparm, loadparm, 8);
> }
> }
> +
> +void sclp_read(char *str, size_t len)
> +{
> + ReadEventData *sccb = (void *)_sccb;
> + char *buf = (char *)(&sccb->ebh) + 7;
> +
> + /* Len should not exceed the maximum size of the event buffer */
> + if (len > SCCB_SIZE - 8) {
> + len = SCCB_SIZE - 8;
> + }
> +
> + sccb->h.length = SCCB_SIZE;
> + sccb->h.function_code = SCLP_UNCONDITIONAL_READ;
> + sccb->ebh.length = sizeof(EventBufferHeader);
> + sccb->ebh.type = SCLP_EVENT_ASCII_CONSOLE_DATA;
> + sccb->ebh.flags = 0;
> +
> + sclp_service_call(SCLP_CMD_READ_EVENT_DATA, sccb);
> + memcpy(str, buf, len);
> +}
> diff --git a/pc-bios/s390-ccw/virtio.c b/pc-bios/s390-ccw/virtio.c
> index c890a03..817e7f5 100644
> --- a/pc-bios/s390-ccw/virtio.c
> +++ b/pc-bios/s390-ccw/virtio.c
> @@ -176,7 +176,7 @@ void vring_send_buf(VRing *vr, void *p, int len, int
> flags)
> }
> }
>
> -static u64 get_clock(void)
> +u64 get_clock(void)
> {
> u64 r;
>
>
--
Thanks,
David / dhildenb
