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| author | Lee Leahy <leroy.p.leahy@intel.com> | 2016-04-23 07:58:27 -0700 |
|---|---|---|
| committer | Leroy P Leahy <leroy.p.leahy@intel.com> | 2016-04-30 15:40:20 +0200 |
| commit | 6bcbe5749b9f1a82004299bb63fba7e99b8ed358 (patch) | |
| tree | bed3efa66c5d56b50a78515b29184c7e39404bda /src/lib | |
| parent | 733b39aed4b12aa1e6ec5b4b7db9bb48ba88e015 (diff) | |
| download | coreboot-6bcbe5749b9f1a82004299bb63fba7e99b8ed358.tar.xz | |
lib/regscript: Add exclusive-or (xor) support
Add xor support which enables toggling of a bit:
* REG_SCRIPT_COMMAND_RXW enum value
* REG_*_RXW* macros to support using REG_SCRIPT_COMMAND_RXW
* REG_*_XOR* macros to support using REG_SCRIPT_COMMAND_RXW
* reg_script_rxw routine to perform and/xor operation
* case in reg_script_run_step to call reg_script_rxw
TEST=Build and run on Galileo Gen2
Change-Id: I50a492c7c2643df5dc2d2fa7113e3722c1e480c7
Signed-off-by: Lee Leahy <leroy.p.leahy@intel.com>
Reviewed-on: https://review.coreboot.org/14495
Tested-by: build bot (Jenkins)
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Diffstat (limited to 'src/lib')
| -rw-r--r-- | src/lib/reg_script.c | 38 |
1 files changed, 38 insertions, 0 deletions
diff --git a/src/lib/reg_script.c b/src/lib/reg_script.c index 7f8200006e..7530dc32b8 100644 --- a/src/lib/reg_script.c +++ b/src/lib/reg_script.c @@ -521,6 +521,41 @@ static void reg_script_rmw(struct reg_script_context *ctx) reg_script_set_step(ctx, step); } +static void reg_script_rxw(struct reg_script_context *ctx) +{ + uint64_t value; + const struct reg_script *step = reg_script_get_step(ctx); + struct reg_script write_step = *step; + +/* + * XOR logic table + * Input XOR Value + * 0 0 0 + * 0 1 1 + * 1 0 1 + * 1 1 0 + * + * Supported operations + * + * Input Mask Temp XOR Value Operation + * 0 0 0 0 0 Clear bit + * 1 0 0 0 0 + * 0 0 0 1 1 Set bit + * 1 0 0 1 1 + * 0 1 0 0 0 Preserve bit + * 1 1 1 0 1 + * 0 1 0 1 1 Toggle bit + * 1 1 1 1 0 + */ + value = reg_script_read(ctx); + value &= step->mask; + value ^= step->value; + write_step.value = value; + reg_script_set_step(ctx, &write_step); + reg_script_write(ctx); + reg_script_set_step(ctx, step); +} + /* In order to easily chain scripts together handle the REG_SCRIPT_COMMAND_NEXT * as recursive call with a new context that has the same dev and resource * as the previous one. That will run to completion and then move on to the @@ -544,6 +579,9 @@ static void reg_script_run_step(struct reg_script_context *ctx, case REG_SCRIPT_COMMAND_RMW: reg_script_rmw(ctx); break; + case REG_SCRIPT_COMMAND_RXW: + reg_script_rxw(ctx); + break; case REG_SCRIPT_COMMAND_POLL: for (try = 0; try < step->timeout; try += POLL_DELAY) { value = reg_script_read(ctx) & step->mask; |