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b=ZK3HiHm/W3xscNsjdEhikDMqYugpd2+7x32l2F8BGZ7//54WOQRxX/W2cGR3R6srBHDu I8DY293JM4mR0nSFCr+/4AxzzoOdQsA3/mwdEAwwIfUHgz8NPFBkmpfY8Mycq1hpLrsN ZYjG5nv0EwFGSeytk2RBV0iauxkhEkax63W8X0Yo18LUomJRc8EZ15MYux4UbCsOYaBK pwEuMubgx/ASL6PXJtDEYZZsQuIykUCuy8siDY5EI0z3wVBscFxjdbA6y7jIodDoJ975 z1jZn1p1NxQI0MjYZFC348+g1oXoqqn2vWC8Lkha/CWQ4pbxfsbaO81JbGDTLuycGQU0 aQ== From: Saif Abrar To: qemu-ppc@nongnu.org, qemu-devel@nongnu.org Cc: clg@kaod.org, npiggin@gmail.com, fbarrat@linux.ibm.com, mst@redhat.com, marcel.apfelbaum@gmail.com, cohuck@redhat.com, pbonzini@redhat.com, thuth@redhat.com, lvivier@redhat.com, saif.abrar@linux.vnet.ibm.com Subject: [PATCH 04/10] pnv/phb4: Implement read-only and write-only bits of registers Date: Thu, 21 Mar 2024 05:04:16 -0500 Message-Id: <20240321100422.5347-5-saif.abrar@linux.vnet.ibm.com> X-Mailer: git-send-email 2.39.3 In-Reply-To: <20240321100422.5347-1-saif.abrar@linux.vnet.ibm.com> References: <20240321100422.5347-1-saif.abrar@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-TM-AS-GCONF: 00 X-Proofpoint-ORIG-GUID: tAlCiII9x4wgr8pLXPyYvOFxHtLr_q9q X-Proofpoint-GUID: uRUglKNcNg7Aes-FcJ9QqFprFA2lH9zY X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.272,Aquarius:18.0.1011,Hydra:6.0.619,FMLib:17.11.176.26 definitions=2024-03-21_06,2024-03-18_03,2023-05-22_02 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 malwarescore=0 adultscore=0 phishscore=0 bulkscore=0 mlxlogscore=999 spamscore=0 clxscore=1015 suspectscore=0 impostorscore=0 mlxscore=0 lowpriorityscore=0 priorityscore=1501 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2403140000 definitions=main-2403210069 Received-SPF: pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Received-SPF: none client-ip=148.163.156.1; envelope-from=saif.abrar@linux.vnet.ibm.com; helo=mx0a-001b2d01.pphosted.com X-Spam_score_int: -19 X-Spam_score: -2.0 X-Spam_bar: -- X-Spam_report: (-2.0 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_NONE=0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: qemu-devel-bounces+importer=patchew.org@nongnu.org X-ZohoMail-DKIM: pass (identity @ibm.com) X-ZM-MESSAGEID: 1711015530210100001 Content-Type: text/plain; charset="utf-8" SW cannot write the read-only(RO) bits of a register and write-only(WO) bits of a register return 0 when read. Added ro_mask[] for each register that defines which bits in that register are RO. When writing to a register, the RO-bits are not updated. When reading a register, clear the WO bits and return the updated value. Tested the registers PHB_DMA_SYNC, PHB_PCIE_HOTPLUG_STATUS, PHB_PCIE_LMR, PHB_PCIE_DLP_TRWCTL, PHB_LEM_ERROR_AND_MASK and PHB_LEM_ERROR_OR_MASK by writing all 1's and reading back the value. The WO bits in these registers should read back as 0. Signed-off-by: Saif Abrar --- hw/pci-host/pnv_phb4.c | 77 ++++++++++++++++++++++++++--- include/hw/pci-host/pnv_phb4.h | 7 +++ include/hw/pci-host/pnv_phb4_regs.h | 19 +++++-- tests/qtest/pnv-phb4-test.c | 60 +++++++++++++++++++++- 4 files changed, 150 insertions(+), 13 deletions(-) diff --git a/hw/pci-host/pnv_phb4.c b/hw/pci-host/pnv_phb4.c index b3a83837f8..a81763f34c 100644 --- a/hw/pci-host/pnv_phb4.c +++ b/hw/pci-host/pnv_phb4.c @@ -735,6 +735,10 @@ static void pnv_phb4_reg_write(void *opaque, hwaddr of= f, uint64_t val, return; } =20 + /* Update 'val' according to the register's RO-mask */ + val =3D (phb->regs[off >> 3] & phb->ro_mask[off >> 3]) | + (val & ~(phb->ro_mask[off >> 3])); + /* Record whether it changed */ changed =3D phb->regs[off >> 3] !=3D val; =20 @@ -808,7 +812,7 @@ static void pnv_phb4_reg_write(void *opaque, hwaddr off= , uint64_t val, case PHB_TCE_TAG_ENABLE: case PHB_INT_NOTIFY_ADDR: case PHB_INT_NOTIFY_INDEX: - case PHB_DMARD_SYNC: + case PHB_DMA_SYNC: break; =20 /* Noise on anything else */ @@ -846,7 +850,7 @@ static uint64_t pnv_phb4_reg_read(void *opaque, hwaddr = off, unsigned size) case PHB_VERSION: return PNV_PHB4_PEC_GET_CLASS(phb->pec)->version; =20 - /* Read-only */ + /* Read-only */ case PHB_PHB4_GEN_CAP: return 0xe4b8000000000000ull; case PHB_PHB4_TCE_CAP: @@ -856,18 +860,49 @@ static uint64_t pnv_phb4_reg_read(void *opaque, hwadd= r off, unsigned size) case PHB_PHB4_EEH_CAP: return phb->big_phb ? 0x2000000000000000ull : 0x1000000000000000ul= l; =20 + /* Write-only, read will return zeros */ + case PHB_LEM_ERROR_AND_MASK: + case PHB_LEM_ERROR_OR_MASK: + return 0; + case PHB_PCIE_DLP_TRWCTL: + val &=3D ~PHB_PCIE_DLP_TRWCTL_WREN; + return val; /* IODA table accesses */ case PHB_IODA_DATA0: return pnv_phb4_ioda_read(phb); =20 + /* + * DMA sync: make it look like it's complete, + * clear write-only read/write start sync bits. + */ + case PHB_DMA_SYNC: + val =3D PHB_DMA_SYNC_RD_COMPLETE | + ~(PHB_DMA_SYNC_RD_START | PHB_DMA_SYNC_WR_START); + return val; + + /* + * PCI-E Stack registers + */ + case PHB_PCIE_SCR: + val |=3D PHB_PCIE_SCR_PLW_X16; /* RO bit */ + break; + /* Link training always appears trained */ case PHB_PCIE_DLP_TRAIN_CTL: /* TODO: Do something sensible with speed ? */ - return PHB_PCIE_DLP_INBAND_PRESENCE | PHB_PCIE_DLP_TL_LINKACT; + val |=3D PHB_PCIE_DLP_INBAND_PRESENCE | PHB_PCIE_DLP_TL_LINKACT; + return val; + + case PHB_PCIE_HOTPLUG_STATUS: + /* Clear write-only bit */ + val &=3D ~PHB_PCIE_HPSTAT_RESAMPLE; + return val; =20 - /* DMA read sync: make it look like it's complete */ - case PHB_DMARD_SYNC: - return PHB_DMARD_SYNC_COMPLETE; + /* Link Management Register */ + case PHB_PCIE_LMR: + /* These write-only bits always read as 0 */ + val &=3D ~(PHB_PCIE_LMR_CHANGELW | PHB_PCIE_LMR_RETRAINLINK); + return val; =20 /* Silent simple reads */ case PHB_LSI_SOURCE_ID: @@ -1712,6 +1747,33 @@ static PCIIOMMUOps pnv_phb4_iommu_ops =3D { .get_address_space =3D pnv_phb4_dma_iommu, }; =20 +static void pnv_phb4_ro_mask_init(PnvPHB4 *phb) +{ + /* Clear RO-mask to make all regs as R/W by default */ + memset(phb->ro_mask, 0x0, PNV_PHB4_NUM_REGS * sizeof(uint64_t)); + + /* + * Set register specific RO-masks + */ + + /* PBL - Error Injection Register (0x1910) */ + phb->ro_mask[PHB_PBL_ERR_INJECT >> 3] =3D + PPC_BITMASK(0, 23) | PPC_BITMASK(28, 35) | PPC_BIT(38) | PPC_BIT(4= 6) | + PPC_BITMASK(49, 51) | PPC_BITMASK(55, 63); + + /* Reserved bits[60:63] */ + phb->ro_mask[PHB_TXE_ERR_LEM_ENABLE >> 3] =3D + phb->ro_mask[PHB_TXE_ERR_AIB_FENCE_ENABLE >> 3] =3D PPC_BITMASK(60, 63= ); + /* Reserved bits[36:63] */ + phb->ro_mask[PHB_RXE_TCE_ERR_LEM_ENABLE >> 3] =3D + phb->ro_mask[PHB_RXE_TCE_ERR_AIB_FENCE_ENABLE >> 3] =3D PPC_BITMASK(36= , 63); + /* Reserved bits[40:63] */ + phb->ro_mask[PHB_ERR_LEM_ENABLE >> 3] =3D + phb->ro_mask[PHB_ERR_AIB_FENCE_ENABLE >> 3] =3D PPC_BITMASK(40, 63); + + /* TODO: Add more RO-masks as regs are implemented in the model */ +} + static void pnv_phb4_err_reg_reset(PnvPHB4 *phb) { STICKY_RST(PHB_ERR_STATUS, 0, PPC_BITMASK(0, 33)); @@ -1782,6 +1844,9 @@ static void pnv_phb4_instance_init(Object *obj) =20 /* XIVE interrupt source object */ object_initialize_child(obj, "source", &phb->xsrc, TYPE_XIVE_SOURCE); + + /* Initialize RO-mask of registers */ + pnv_phb4_ro_mask_init(phb); } =20 void pnv_phb4_bus_init(DeviceState *dev, PnvPHB4 *phb) diff --git a/include/hw/pci-host/pnv_phb4.h b/include/hw/pci-host/pnv_phb4.h index 3212e68160..91e81eee0e 100644 --- a/include/hw/pci-host/pnv_phb4.h +++ b/include/hw/pci-host/pnv_phb4.h @@ -94,6 +94,13 @@ struct PnvPHB4 { uint64_t regs[PNV_PHB4_NUM_REGS]; MemoryRegion mr_regs; =20 + /* + * Read-only bitmask for registers + * Bit value: 1 =3D> RO bit + * 0 =3D> RW bit + */ + uint64_t ro_mask[PNV_PHB4_NUM_REGS]; + /* Extra SCOM-only register */ uint64_t scom_hv_ind_addr_reg; =20 diff --git a/include/hw/pci-host/pnv_phb4_regs.h b/include/hw/pci-host/pnv_= phb4_regs.h index df5e86d29a..391d6a89ea 100644 --- a/include/hw/pci-host/pnv_phb4_regs.h +++ b/include/hw/pci-host/pnv_phb4_regs.h @@ -180,9 +180,11 @@ #define PHB_M64_AOMASK 0x1d0 #define PHB_M64_UPPER_BITS 0x1f0 #define PHB_NXLATE_PREFIX 0x1f8 -#define PHB_DMARD_SYNC 0x200 -#define PHB_DMARD_SYNC_START PPC_BIT(0) -#define PHB_DMARD_SYNC_COMPLETE PPC_BIT(1) +#define PHB_DMA_SYNC 0x200 +#define PHB_DMA_SYNC_RD_START PPC_BIT(0) +#define PHB_DMA_SYNC_RD_COMPLETE PPC_BIT(1) +#define PHB_DMA_SYNC_WR_START PPC_BIT(2) +#define PHB_DMA_SYNC_WR_COMPLETE PPC_BIT(3) #define PHB_RTC_INVALIDATE 0x208 #define PHB_RTC_INVALIDATE_ALL PPC_BIT(0) #define PHB_RTC_INVALIDATE_RID PPC_BITMASK(16, 31) @@ -395,8 +397,8 @@ #define PHB_PCIE_SCR 0x1A00 #define PHB_PCIE_SCR_SLOT_CAP PPC_BIT(15) #define PHB_PCIE_SCR_MAXLINKSPEED PPC_BITMASK(32, 35) +#define PHB_PCIE_SCR_PLW_X16 PPC_BIT(41) /* x16 */ #define PHB_PCIE_BNR 0x1A08 - #define PHB_PCIE_CRESET 0x1A10 #define PHB_PCIE_CRESET_CFG_CORE PPC_BIT(0) #define PHB_PCIE_CRESET_TLDLP PPC_BIT(1) @@ -405,7 +407,14 @@ #define PHB_PCIE_CRESET_PIPE_N PPC_BIT(4) #define PHB_PCIE_CRESET_REFCLK_N PPC_BIT(8) #define PHB_PCIE_HOTPLUG_STATUS 0x1A20 +#define PHB_PCIE_HPSTAT_SIMDIAG PPC_BIT(3) +#define PHB_PCIE_HPSTAT_RESAMPLE PPC_BIT(9) #define PHB_PCIE_HPSTAT_PRESENCE PPC_BIT(10) +#define PHB_PCIE_HPSTAT_LINKACTIVE PPC_BIT(12) +#define PHB_PCIE_LMR 0x1A30 +#define PHB_PCIE_LMR_CHANGELW PPC_BIT(0) +#define PHB_PCIE_LMR_RETRAINLINK PPC_BIT(1) +#define PHB_PCIE_LMR_LINKACTIVE PPC_BIT(8) =20 #define PHB_PCIE_DLP_TRAIN_CTL 0x1A40 #define PHB_PCIE_DLP_LINK_WIDTH PPC_BITMASK(30, 35) @@ -433,7 +442,7 @@ =20 #define PHB_PCIE_DLP_TRWCTL 0x1A80 #define PHB_PCIE_DLP_TRWCTL_EN PPC_BIT(0) - +#define PHB_PCIE_DLP_TRWCTL_WREN PPC_BIT(1) #define PHB_PCIE_DLP_ERRLOG1 0x1AA0 #define PHB_PCIE_DLP_ERRLOG2 0x1AA8 #define PHB_PCIE_DLP_ERR_STATUS 0x1AB0 diff --git a/tests/qtest/pnv-phb4-test.c b/tests/qtest/pnv-phb4-test.c index 708df3867c..0c8e58dd5f 100644 --- a/tests/qtest/pnv-phb4-test.c +++ b/tests/qtest/pnv-phb4-test.c @@ -75,7 +75,8 @@ static void phb4_sticky_rst_test(QTestState *qts) * Sticky reset test of PHB_PBL_ERR_STATUS. * * Write all 1's to reg PHB_PBL_ERR_INJECT. - * Updated value will be copied to reg PHB_PBL_ERR_STATUS. + * RO-only bits will not be written and + * updated value will be copied to reg PHB_PBL_ERR_STATUS. * * Reset PBL core by setting PHB_PCIE_CRESET_PBL in reg PHB_PCIE_CRESE= T. * Verify the sticky bits are still set. @@ -83,7 +84,59 @@ static void phb4_sticky_rst_test(QTestState *qts) pnv_phb4_xscom_write(qts, PHB_PBL_ERR_INJECT, PPC_BITMASK(0, 63)); pnv_phb4_xscom_write(qts, PHB_PCIE_CRESET, PHB_PCIE_CRESET_PBL); /*Res= et*/ val =3D pnv_phb4_xscom_read(qts, PHB_PBL_ERR_STATUS); - g_assert_cmpuint(val, =3D=3D, (PPC_BITMASK(0, 9) | PPC_BITMASK(12, 63)= )); + g_assert_cmpuint(val, =3D=3D, 0xF00DFD8E00); +} + +/* Check that write-only bits/regs return 0 when read */ +static void phb4_writeonly_read_test(QTestState *qts) +{ + uint64_t val; + + /* + * Set all bits of PHB_DMA_SYNC, + * bits 0 and 2 are write-only and should be read as 0. + */ + pnv_phb4_xscom_write(qts, PHB_DMA_SYNC, PPC_BITMASK(0, 63)); + val =3D pnv_phb4_xscom_read(qts, PHB_DMA_SYNC); + g_assert_cmpuint(val & PPC_BIT(0), =3D=3D, 0x0); + g_assert_cmpuint(val & PPC_BIT(2), =3D=3D, 0x0); + + /* + * Set all bits of PHB_PCIE_HOTPLUG_STATUS, + * bit 9 is write-only and should be read as 0. + */ + pnv_phb4_xscom_write(qts, PHB_PCIE_HOTPLUG_STATUS, PPC_BITMASK(0, 63)); + val =3D pnv_phb4_xscom_read(qts, PHB_PCIE_HOTPLUG_STATUS); + g_assert_cmpuint(val & PPC_BIT(9), =3D=3D, 0x0); + + /* + * Set all bits of PHB_PCIE_LMR, + * bits 0 and 1 are write-only and should be read as 0. + */ + pnv_phb4_xscom_write(qts, PHB_PCIE_LMR, PPC_BITMASK(0, 63)); + val =3D pnv_phb4_xscom_read(qts, PHB_PCIE_LMR); + g_assert_cmpuint(val & PPC_BIT(0), =3D=3D, 0x0); + g_assert_cmpuint(val & PPC_BIT(1), =3D=3D, 0x0); + + /* + * Set all bits of PHB_PCIE_DLP_TRWCTL, + * write-only bit-1 should be read as 0. + */ + pnv_phb4_xscom_write(qts, PHB_PCIE_DLP_TRWCTL, PPC_BITMASK(0, 63)); + val =3D pnv_phb4_xscom_read(qts, PHB_PCIE_DLP_TRWCTL); + g_assert_cmpuint(val & PPC_BIT(1), =3D=3D, 0x0); + + /* + * Set all bits of PHB_LEM_ERROR_AND_MASK, PHB_LEM_ERROR_OR_MASK, + * both regs are write-only and should be read as 0. + */ + pnv_phb4_xscom_write(qts, PHB_LEM_ERROR_AND_MASK, PPC_BITMASK(0, 63)); + val =3D pnv_phb4_xscom_read(qts, PHB_LEM_ERROR_AND_MASK); + g_assert_cmpuint(val, =3D=3D, 0x0); + + pnv_phb4_xscom_write(qts, PHB_LEM_ERROR_OR_MASK, PPC_BITMASK(0, 63)); + val =3D pnv_phb4_xscom_read(qts, PHB_LEM_ERROR_OR_MASK); + g_assert_cmpuint(val, =3D=3D, 0x0); } =20 static void test_phb4(void) @@ -101,6 +154,9 @@ static void test_phb4(void) /* Check sticky reset of a register */ phb4_sticky_rst_test(qts); =20 + /* Check write-only logic */ + phb4_writeonly_read_test(qts); + qtest_quit(qts); } =20 --=20 2.39.3