linux/arch/arm64/tools/gen-sysreg.awk
Mark Rutland 013ecd4439 arm64/sysreg: allow *Enum blocks in SysregFields blocks
We'd like to support Enum/SignedEnum/UnsignedEnum blocks within
SysregFields blocks, so that we can define enumerations for sets of
registers. This isn't currently supported by gen-sysreg.awk due to the
way we track the active block, which can't handle more than a single
layer of nesting, which imposes an awkward requirement that when ending
a block we know what the parent block is when calling change_block()

Make this nicer by using a stack of active blocks, with block_push() to
start a block, and block_pop() to end a block. Doing so means that we
only need to check the active block at the start of parsing a line: for
the start of a block we can check the parent is valid, and for the end
of a block we check that the active block is valid.

This structure makes the block parsing simpler and makes it easy to
permit a block to live under several potential parents (e.g. by
permitting Enum to start when the active block is Sysreg or
SysregFields). It also permits further nesting, if we need that in
future.

To aid debugging, the stack of active blocks is reported for fatal
errors, and an error is raised if the file is terminated without ending
the active block. For clarity I've renamed the top-level element from
"None" to "Root".

The Fields element it intended only for use within Sysreg blocks, and
does not make sense within SysregFields blocks, and so remains forbidden
within a SysregFields block.

I've verified using sha1sum that this patch does not change the
current generated contents of <asm/sysreg-defs.h>.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Mark Brown <broonie@kernel.org>
Cc: Will Deacon <will@kernel.org>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20230306114836.2575432-1-mark.rutland@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
2023-04-06 15:28:54 +01:00

337 lines
6.5 KiB
Awk
Executable File

#!/bin/awk -f
# SPDX-License-Identifier: GPL-2.0
# gen-sysreg.awk: arm64 sysreg header generator
#
# Usage: awk -f gen-sysreg.awk sysregs.txt
function block_current() {
return __current_block[__current_block_depth];
}
# Log an error and terminate
function fatal(msg) {
print "Error at " NR ": " msg > "/dev/stderr"
printf "Current block nesting:"
for (i = 0; i <= __current_block_depth; i++) {
printf " " __current_block[i]
}
printf "\n"
exit 1
}
# Enter a new block, setting the active block to @block
function block_push(block) {
__current_block[++__current_block_depth] = block
}
# Exit a block, setting the active block to the parent block
function block_pop() {
if (__current_block_depth == 0)
fatal("error: block_pop() in root block")
__current_block_depth--;
}
# Sanity check the number of records for a field makes sense. If not, produce
# an error and terminate.
function expect_fields(nf) {
if (NF != nf)
fatal(NF " fields found where " nf " expected")
}
# Print a CPP macro definition, padded with spaces so that the macro bodies
# line up in a column
function define(name, val) {
printf "%-56s%s\n", "#define " name, val
}
# Print standard BITMASK/SHIFT/WIDTH CPP definitions for a field
function define_field(reg, field, msb, lsb) {
define(reg "_" field, "GENMASK(" msb ", " lsb ")")
define(reg "_" field "_MASK", "GENMASK(" msb ", " lsb ")")
define(reg "_" field "_SHIFT", lsb)
define(reg "_" field "_WIDTH", msb - lsb + 1)
}
# Print a field _SIGNED definition for a field
function define_field_sign(reg, field, sign) {
define(reg "_" field "_SIGNED", sign)
}
# Parse a "<msb>[:<lsb>]" string into the global variables @msb and @lsb
function parse_bitdef(reg, field, bitdef, _bits)
{
if (bitdef ~ /^[0-9]+$/) {
msb = bitdef
lsb = bitdef
} else if (split(bitdef, _bits, ":") == 2) {
msb = _bits[1]
lsb = _bits[2]
} else {
fatal("invalid bit-range definition '" bitdef "'")
}
if (msb != next_bit)
fatal(reg "." field " starts at " msb " not " next_bit)
if (63 < msb || msb < 0)
fatal(reg "." field " invalid high bit in '" bitdef "'")
if (63 < lsb || lsb < 0)
fatal(reg "." field " invalid low bit in '" bitdef "'")
if (msb < lsb)
fatal(reg "." field " invalid bit-range '" bitdef "'")
if (low > high)
fatal(reg "." field " has invalid range " high "-" low)
next_bit = lsb - 1
}
BEGIN {
print "#ifndef __ASM_SYSREG_DEFS_H"
print "#define __ASM_SYSREG_DEFS_H"
print ""
print "/* Generated file - do not edit */"
print ""
__current_block_depth = 0
__current_block[__current_block_depth] = "Root"
}
END {
if (__current_block_depth != 0)
fatal("Missing terminator for " block_current() " block")
print "#endif /* __ASM_SYSREG_DEFS_H */"
}
# skip blank lines and comment lines
/^$/ { next }
/^[\t ]*#/ { next }
/^SysregFields/ && block_current() == "Root" {
block_push("SysregFields")
expect_fields(2)
reg = $2
res0 = "UL(0)"
res1 = "UL(0)"
unkn = "UL(0)"
next_bit = 63
next
}
/^EndSysregFields/ && block_current() == "SysregFields" {
if (next_bit > 0)
fatal("Unspecified bits in " reg)
define(reg "_RES0", "(" res0 ")")
define(reg "_RES1", "(" res1 ")")
define(reg "_UNKN", "(" unkn ")")
print ""
reg = null
res0 = null
res1 = null
unkn = null
block_pop()
next
}
/^Sysreg/ && block_current() == "Root" {
block_push("Sysreg")
expect_fields(7)
reg = $2
op0 = $3
op1 = $4
crn = $5
crm = $6
op2 = $7
res0 = "UL(0)"
res1 = "UL(0)"
unkn = "UL(0)"
define("REG_" reg, "S" op0 "_" op1 "_C" crn "_C" crm "_" op2)
define("SYS_" reg, "sys_reg(" op0 ", " op1 ", " crn ", " crm ", " op2 ")")
define("SYS_" reg "_Op0", op0)
define("SYS_" reg "_Op1", op1)
define("SYS_" reg "_CRn", crn)
define("SYS_" reg "_CRm", crm)
define("SYS_" reg "_Op2", op2)
print ""
next_bit = 63
next
}
/^EndSysreg/ && block_current() == "Sysreg" {
if (next_bit > 0)
fatal("Unspecified bits in " reg)
if (res0 != null)
define(reg "_RES0", "(" res0 ")")
if (res1 != null)
define(reg "_RES1", "(" res1 ")")
if (unkn != null)
define(reg "_UNKN", "(" unkn ")")
if (res0 != null || res1 != null || unkn != null)
print ""
reg = null
op0 = null
op1 = null
crn = null
crm = null
op2 = null
res0 = null
res1 = null
unkn = null
block_pop()
next
}
# Currently this is effectivey a comment, in future we may want to emit
# defines for the fields.
/^Fields/ && block_current() == "Sysreg" {
expect_fields(2)
if (next_bit != 63)
fatal("Some fields already defined for " reg)
print "/* For " reg " fields see " $2 " */"
print ""
next_bit = 0
res0 = null
res1 = null
unkn = null
next
}
/^Res0/ && (block_current() == "Sysreg" || block_current() == "SysregFields") {
expect_fields(2)
parse_bitdef(reg, "RES0", $2)
field = "RES0_" msb "_" lsb
res0 = res0 " | GENMASK_ULL(" msb ", " lsb ")"
next
}
/^Res1/ && (block_current() == "Sysreg" || block_current() == "SysregFields") {
expect_fields(2)
parse_bitdef(reg, "RES1", $2)
field = "RES1_" msb "_" lsb
res1 = res1 " | GENMASK_ULL(" msb ", " lsb ")"
next
}
/^Unkn/ && (block_current() == "Sysreg" || block_current() == "SysregFields") {
expect_fields(2)
parse_bitdef(reg, "UNKN", $2)
field = "UNKN_" msb "_" lsb
unkn = unkn " | GENMASK_ULL(" msb ", " lsb ")"
next
}
/^Field/ && (block_current() == "Sysreg" || block_current() == "SysregFields") {
expect_fields(3)
field = $3
parse_bitdef(reg, field, $2)
define_field(reg, field, msb, lsb)
print ""
next
}
/^Raz/ && (block_current() == "Sysreg" || block_current() == "SysregFields") {
expect_fields(2)
parse_bitdef(reg, field, $2)
next
}
/^SignedEnum/ && (block_current() == "Sysreg" || block_current() == "SysregFields") {
block_push("Enum")
expect_fields(3)
field = $3
parse_bitdef(reg, field, $2)
define_field(reg, field, msb, lsb)
define_field_sign(reg, field, "true")
next
}
/^UnsignedEnum/ && (block_current() == "Sysreg" || block_current() == "SysregFields") {
block_push("Enum")
expect_fields(3)
field = $3
parse_bitdef(reg, field, $2)
define_field(reg, field, msb, lsb)
define_field_sign(reg, field, "false")
next
}
/^Enum/ && (block_current() == "Sysreg" || block_current() == "SysregFields") {
block_push("Enum")
expect_fields(3)
field = $3
parse_bitdef(reg, field, $2)
define_field(reg, field, msb, lsb)
next
}
/^EndEnum/ && block_current() == "Enum" {
field = null
msb = null
lsb = null
print ""
block_pop()
next
}
/0b[01]+/ && block_current() == "Enum" {
expect_fields(2)
val = $1
name = $2
define(reg "_" field "_" name, "UL(" val ")")
next
}
# Any lines not handled by previous rules are unexpected
{
fatal("unhandled statement")
}