target/arm: provide stubs for more external debug registers

Qemu doesn't implement Debug Communication Channel, as well as the rest
of external debug interface. However, Microsoft Hyper-V in tries to
access some of those registers during an EL2 context switch.

Since there is no architectural way to not advertise support for external
debug, provide RAZ/WI stubs for OSDTRRX_EL1, OSDTRTX_EL1 and OSECCR_EL1
registers in the same way the rest of DCM is currently done. Do account
for access traps though with access_tda.

Signed-off-by: Evgeny Iakovlev <eiakovlev@linux.microsoft.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 20230120155929.32384-3-eiakovlev@linux.microsoft.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
This commit is contained in:
Evgeny Iakovlev 2023-01-20 16:59:29 +01:00 committed by Peter Maydell
parent 5fc83f1128
commit b3aa2f2128

View File

@ -682,6 +682,27 @@ static const ARMCPRegInfo debug_cp_reginfo[] = {
.opc0 = 2, .opc1 = 3, .crn = 0, .crm = 1, .opc2 = 0,
.access = PL0_R, .accessfn = access_tda,
.type = ARM_CP_CONST, .resetvalue = 0 },
/*
* OSDTRRX_EL1/OSDTRTX_EL1 are used for save and restore of DBGDTRRX_EL0.
* It is a component of the Debug Communications Channel, which is not implemented.
*/
{ .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,
.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,
.type = ARM_CP_CONST, .resetvalue = 0 },
/*
* OSECCR_EL1 provides a mechanism for an operating system
* to access the contents of EDECCR. EDECCR is not implemented though,
* as is the rest of external device mechanism.
*/
{ .name = "OSECCR_EL1", .state = ARM_CP_STATE_BOTH, .cp = 14,
.opc0 = 2, .opc1 = 0, .crn = 0, .crm = 6, .opc2 = 2,
.access = PL1_RW, .accessfn = access_tda,
.type = ARM_CP_CONST, .resetvalue = 0 },
/*
* DBGDSCRint[15,12,5:2] map to MDSCR_EL1[15,12,5:2]. Map all bits as
* it is unlikely a guest will care.