OpenE2K/qemu-e2k
13
4
Fork 0
Code Issues 4 Pull Requests Projects 2 Releases Activity

target/arm: Implement MDCR_EL2.TDCC and MDCR_EL3.TDCC traps

Browse Source 
FEAT_FGT also implements an extra trap bit in the MDCR_EL2 and
MDCR_EL3 registers: bit TDCC enables trapping of use of the Debug
Comms Channel registers OSDTRRX_EL1, OSDTRTX_EL1, MDCCSR_EL0,
MDCCINT_EL0, DBGDTR_EL0, DBGDTRRX_EL0 and DBGDTRTX_EL0 (and their
AArch32 equivalents).  This trapping is independent of whether
fine-grained traps are enabled or not.

Implement these extra traps.  (We don't implement DBGDTR_EL0,
DBGDTRRX_EL0 and DBGDTRTX_EL0.)

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Tested-by: Fuad Tabba <tabba@google.com>
Message-id: 20230130182459.3309057-23-peter.maydell@linaro.org
Message-id: 20230127175507.2895013-23-peter.maydell@linaro.org
This commit is contained in:
Peter Maydell 2023-01-30 18:24:58 +00:00
parent 34a8a07e57
commit 1748ef03c5
1 changed files with 31 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

35
target/arm/debug_helper.c
View File

@ -599,6 +599,33 @@ static CPAccessResult access_tda(CPUARMState *env, const ARMCPRegInfo *ri,
return CP_ACCESS_OK;
}
/*
* Check for traps to Debug Comms Channel registers. If FEAT_FGT
* is implemented then these are controlled by MDCR_EL2.TDCC for
* EL2 and MDCR_EL3.TDCC for EL3. They are also controlled by
* the general debug access trap bits MDCR_EL2.TDA and MDCR_EL3.TDA.
*/
static CPAccessResult access_tdcc(CPUARMState *env, const ARMCPRegInfo *ri,
bool isread)
{
int el = arm_current_el(env);
uint64_t mdcr_el2 = arm_mdcr_el2_eff(env);
bool mdcr_el2_tda = (mdcr_el2 & MDCR_TDA) || (mdcr_el2 & MDCR_TDE) ||
(arm_hcr_el2_eff(env) & HCR_TGE);
bool mdcr_el2_tdcc = cpu_isar_feature(aa64_fgt, env_archcpu(env)) &&
(mdcr_el2 & MDCR_TDCC);
bool mdcr_el3_tdcc = cpu_isar_feature(aa64_fgt, env_archcpu(env)) &&
(env->cp15.mdcr_el3 & MDCR_TDCC);
if (el < 2 && (mdcr_el2_tda || mdcr_el2_tdcc)) {
return CP_ACCESS_TRAP_EL2;
}
if (el < 3 && ((env->cp15.mdcr_el3 & MDCR_TDA) || mdcr_el3_tdcc)) {
return CP_ACCESS_TRAP_EL3;
}
return CP_ACCESS_OK;
}
static void oslar_write(CPUARMState *env, const ARMCPRegInfo *ri,
uint64_t value)
{
@ -681,7 +708,7 @@ static const ARMCPRegInfo debug_cp_reginfo[] = {
*/
{ .name = "MDCCSR_EL0", .state = ARM_CP_STATE_AA64,
.opc0 = 2, .opc1 = 3, .crn = 0, .crm = 1, .opc2 = 0,
.access = PL0_R, .accessfn = access_tda,
.access = PL0_R, .accessfn = access_tdcc,
.type = ARM_CP_CONST, .resetvalue = 0 },
/*
* OSDTRRX_EL1/OSDTRTX_EL1 are used for save and restore of DBGDTRRX_EL0.
@ -689,11 +716,11 @@ static const ARMCPRegInfo debug_cp_reginfo[] = {
*/
{ .name = "OSDTRRX_EL1", .state = ARM_CP_STATE_BOTH, .cp = 14,
.opc0 = 2, .opc1 = 0, .crn = 0, .crm = 0, .opc2 = 2,
.access = PL1_RW, .accessfn = access_tda,
.access = PL1_RW, .accessfn = access_tdcc,
.type = ARM_CP_CONST, .resetvalue = 0 },
{ .name = "OSDTRTX_EL1", .state = ARM_CP_STATE_BOTH, .cp = 14,
.opc0 = 2, .opc1 = 0, .crn = 0, .crm = 3, .opc2 = 2,
.access = PL1_RW, .accessfn = access_tda,
.access = PL1_RW, .accessfn = access_tdcc,
.type = ARM_CP_CONST, .resetvalue = 0 },
/*
* OSECCR_EL1 provides a mechanism for an operating system
@ -757,7 +784,7 @@ static const ARMCPRegInfo debug_cp_reginfo[] = {
*/
{ .name = "MDCCINT_EL1", .state = ARM_CP_STATE_BOTH,
.cp = 14, .opc0 = 2, .opc1 = 0, .crn = 0, .crm = 2, .opc2 = 0,
.access = PL1_RW, .accessfn = access_tda,
.access = PL1_RW, .accessfn = access_tdcc,
.type = ARM_CP_NOP },
/*
* Dummy DBGCLAIM registers.