Hrvoje Čavrak has uploaded this change for review.
udelay.c: Enable providing delay calibration value through CLI
This commit implements --get-loop-delay/--set-loop-delay options to
retrieve and provide the calibration loop delay through the command line.
The delay calibration procedure can take up to few seconds, which adds up
when executed a number of times consecutively. Therefore, this provides a
means to execute it only once, and then re-use the calibrated value on
subsequent runs. Also, it implements a sanity check, expecting the value
to land within 10% of the theoretical delay expectance, otherwise it
ignores the provided value and runs the calibration procedure instead.
Signed-off-by: Hrvoje Cavrak <hrvoje@hrvoje.org>
Change-Id: I7c9a491c5cb5fb3af56a691a0c6af9b53dcff550
---
M cli_classic.c
M flashrom.8.tmpl
M libflashrom.c
M programmer.h
M udelay.c
5 files changed, 60 insertions(+), 7 deletions(-)
git pull ssh://review.coreboot.org:29418/flashrom refs/changes/17/44517/1
diff --git a/cli_classic.c b/cli_classic.c
index 967ff50..b023c45 100644
--- a/cli_classic.c
+++ b/cli_classic.c
@@ -63,6 +63,8 @@
" -o | --output <logfile> log output to <logfile>\n"
" --flash-contents <ref-file> assume flash contents to be <ref-file>\n"
" -L | --list-supported print supported devices\n"
+ " --set-loop-delay <value> set loop delay calibration manually\n"
+ " --get-loop-delay retrieve loop delay calibration\n"
#if CONFIG_PRINT_WIKI == 1
" -z | --list-supported-wiki print supported devices in wiki syntax\n"
#endif
@@ -118,6 +120,7 @@
int flash_name = 0, flash_size = 0;
int read_it = 0, write_it = 0, erase_it = 0, verify_it = 0;
int dont_verify_it = 0, dont_verify_all = 0, list_supported = 0, operation_specified = 0;
+ unsigned long provided_delay = 0;
struct flashrom_layout *layout = NULL;
enum programmer prog = PROGRAMMER_INVALID;
enum {
@@ -127,6 +130,8 @@
OPTION_FLASH_CONTENTS,
OPTION_FLASH_NAME,
OPTION_FLASH_SIZE,
+ OPTION_GET_LOOP_DELAY,
+ OPTION_SET_LOOP_DELAY,
};
int ret = 0;
@@ -156,6 +161,8 @@
{"help", 0, NULL, 'h'},
{"version", 0, NULL, 'R'},
{"output", 1, NULL, 'o'},
+ {"get-loop-delay", 0, NULL, OPTION_GET_LOOP_DELAY},
+ {"set-loop-delay", 1, NULL, OPTION_SET_LOOP_DELAY},
{NULL, 0, NULL, 0},
};
@@ -365,6 +372,14 @@
}
#endif /* STANDALONE */
break;
+ case OPTION_GET_LOOP_DELAY:
+ /* Make it easy for scripts to parse this by omitting anything else */
+ msg_pinfo("%lu\n", get_calibration_value());
+ exit(0);
+ break;
+ case OPTION_SET_LOOP_DELAY:
+ provided_delay = strtoul(strdup(optarg), NULL, 0);
+ break;
default:
cli_classic_abort_usage(NULL);
break;
@@ -457,7 +472,10 @@
}
/* FIXME: Delay calibration should happen in programmer code. */
- myusec_calibrate_delay();
+ if (provided_delay)
+ set_external_calibration(provided_delay);
+ else
+ myusec_calibrate_delay(0);
if (programmer_init(prog, pparam)) {
msg_perr("Error: Programmer initialization failed.\n");
diff --git a/flashrom.8.tmpl b/flashrom.8.tmpl
index db50d59..4aada91 100644
--- a/flashrom.8.tmpl
+++ b/flashrom.8.tmpl
@@ -50,7 +50,7 @@
[\fB\-E\fR|\fB\-r\fR <file>|\fB\-w\fR <file>|\fB\-v\fR <file>]
[(\fB\-l\fR <file>|\fB\-\-ifd|\fB \-\-fmap\fR|\fB\-\-fmap-file\fR <file>) [\fB\-i\fR <image>]]
[\fB\-n\fR] [\fB\-N\fR] [\fB\-f\fR])]
- [\fB\-V\fR[\fBV\fR[\fBV\fR]]] [\fB-o\fR <logfile>]
+ [\fB\-V\fR[\fBV\fR[\fBV\fR]]] [\fB-o\fR <logfile>] [\fB-d\fR get | <value>]
.SH DESCRIPTION
.B flashrom
is a utility for detecting, reading, writing, verifying and erasing flash
@@ -364,6 +364,17 @@
.TP
.B "\-R, \-\-version"
Show version information and exit.
+.TP
+.B "\-\-get\-loop\-delay"
+Retrieve the loop calibration delay value or provide one externally. Calibrate
+delay procedure can take a few seconds and for repeated execution on a large
+number of hosts it can provide a significant overhead. By getting the value,
+it can later be provided by \-\-set\-loop\-delay
+.TP
+.B "\-\-set\-loop\-delay <value>"
+This argument makes it possible to provide the calibration delay through the
+command line option.
+
.SH PROGRAMMER-SPECIFIC INFORMATION
Some programmer drivers accept further parameters to set programmer-specific
parameters. These parameters are separated from the programmer name by a
diff --git a/libflashrom.c b/libflashrom.c
index ae2d33d..92e2527 100644
--- a/libflashrom.c
+++ b/libflashrom.c
@@ -51,7 +51,7 @@
{
if (perform_selfcheck && selfcheck())
return 1;
- myusec_calibrate_delay();
+ myusec_calibrate_delay(0);
return 0;
}
diff --git a/programmer.h b/programmer.h
index c5cab18..e0925e2 100644
--- a/programmer.h
+++ b/programmer.h
@@ -280,9 +280,11 @@
/* udelay.c */
void myusec_delay(unsigned int usecs);
-void myusec_calibrate_delay(void);
+void myusec_calibrate_delay(int force);
void internal_sleep(unsigned int usecs);
void internal_delay(unsigned int usecs);
+unsigned long get_calibration_value(void);
+void set_external_calibration(unsigned long external_micro);
#if CONFIG_INTERNAL == 1
/* board_enable.c */
diff --git a/udelay.c b/udelay.c
index 6c0efc4..698f1ca 100644
--- a/udelay.c
+++ b/udelay.c
@@ -133,9 +133,9 @@
return timeusec;
}
-void myusec_calibrate_delay(void)
+void myusec_calibrate_delay(int force)
{
- if (clock_check_res())
+ if (clock_check_res() && !force)
return;
unsigned long count = 1000;
@@ -221,6 +221,28 @@
msg_pinfo("OK.\n");
}
+void set_external_calibration(unsigned long external_micro)
+{
+ micro = external_micro;
+ unsigned long elapsed = measure_delay(100000);
+ /* Do a sanity check if the provided parameter makes loops fall
+ * within 10% of the desired value. Otherwise, ignore provided value
+ * and recalibrate.
+ */
+ if (elapsed > 90000 && elapsed < 110000)
+ msg_pinfo("Provided delay is acceptable!\n");
+ else {
+ msg_pinfo("Elapsed: %lu, provided delay is NOT acceptable!\n", elapsed);
+ myusec_calibrate_delay(1); /* Ignore using the system clock for loop timing */
+ }
+}
+
+unsigned long get_calibration_value(void)
+{
+ myusec_calibrate_delay(1); /* Ignore using the system clock for loop timing */
+ return micro;
+}
+
/* Not very precise sleep. */
void internal_sleep(unsigned int usecs)
{
@@ -250,7 +272,7 @@
#else
#include <libpayload.h>
-void myusec_calibrate_delay(void)
+void myusec_calibrate_delay(int force)
{
get_cpu_speed();
}
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