[RFC PATCH 04/21] PCI/IDE: Define Integrity and Data Encryption (IDE) extended capability

[Alexey Kardashevskiy <aik@amd.com>]

PCIe 6.0 introduces the "Integrity & Data Encryption (IDE)" feature which
adds a new capability with id=0x30.

Add the new id to the list of capabilities. Add new flags from pciutils.
Add a module with a helper to control selective IDE capability.

TODO: get rid of lots of magic numbers. It is one annoying flexible
capability to deal with.

Signed-off-by: Alexey Kardashevskiy <aik@amd.com>
---
 drivers/pci/Makefile          |   1 +
 include/linux/pci-ide.h       |  18 ++
 include/uapi/linux/pci_regs.h |  76 +++++++-
 drivers/pci/ide.c             | 186 ++++++++++++++++++++
 drivers/pci/Kconfig           |   4 +
 5 files changed, 284 insertions(+), 1 deletion(-)

diff --git a/drivers/pci/Makefile b/drivers/pci/Makefile
index 1452e4ba7f00..034f17f9297a 100644
--- a/drivers/pci/Makefile
+++ b/drivers/pci/Makefile
@@ -34,6 +34,7 @@ obj-$(CONFIG_PCI_P2PDMA)	+= p2pdma.o
 obj-$(CONFIG_XEN_PCIDEV_FRONTEND) += xen-pcifront.o
 obj-$(CONFIG_VGA_ARB)		+= vgaarb.o
 obj-$(CONFIG_PCI_DOE)		+= doe.o
+obj-$(CONFIG_PCI_IDE)		+= ide.o
 obj-$(CONFIG_PCI_DYNAMIC_OF_NODES) += of_property.o
 
 obj-$(CONFIG_PCI_CMA)		+= cma.o cma.asn1.o
diff --git a/include/linux/pci-ide.h b/include/linux/pci-ide.h
new file mode 100644
index 000000000000..983a8daf1199
--- /dev/null
+++ b/include/linux/pci-ide.h
@@ -0,0 +1,18 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Integrity & Data Encryption (IDE)
+ *	PCIe r6.0, sec 6.33 DOE
+ */
+
+#ifndef LINUX_PCI_IDE_H
+#define LINUX_PCI_IDE_H
+
+int pci_ide_set_sel(struct pci_dev *pdev, unsigned int sel_index, unsigned int streamid,
+		    bool enable, bool def, bool tee_limited, bool ide_cfg);
+int pci_ide_set_sel_rid_assoc(struct pci_dev *pdev, unsigned int sel_index,
+			      bool valid, u8 seg_base, u16 rid_base, u16 rid_limit);
+int pci_ide_set_sel_addr_assoc(struct pci_dev *pdev, unsigned int sel_index, unsigned int blocknum,
+			       bool valid, u64 base, u64 limit);
+int pci_ide_get_sel_sta(struct pci_dev *pdev, unsigned int sel_index, u32 *status);
+
+#endif
diff --git a/include/uapi/linux/pci_regs.h b/include/uapi/linux/pci_regs.h
index 0011a301b8c5..80962b07719a 100644
--- a/include/uapi/linux/pci_regs.h
+++ b/include/uapi/linux/pci_regs.h
@@ -743,7 +743,8 @@
 #define PCI_EXT_CAP_ID_PL_16GT	0x26	/* Physical Layer 16.0 GT/s */
 #define PCI_EXT_CAP_ID_PL_32GT  0x2A    /* Physical Layer 32.0 GT/s */
 #define PCI_EXT_CAP_ID_DOE	0x2E	/* Data Object Exchange */
-#define PCI_EXT_CAP_ID_MAX	PCI_EXT_CAP_ID_DOE
+#define PCI_EXT_CAP_ID_IDE	0x30	/* Integrity and Data Encryption (IDE) */
+#define PCI_EXT_CAP_ID_MAX	PCI_EXT_CAP_ID_IDE
 
 #define PCI_EXT_CAP_DSN_SIZEOF	12
 #define PCI_EXT_CAP_MCAST_ENDPOINT_SIZEOF 40
@@ -1150,9 +1151,82 @@
 #define PCI_DOE_DATA_OBJECT_DISC_RSP_3_PROTOCOL		0x00ff0000
 #define PCI_DOE_DATA_OBJECT_DISC_RSP_3_NEXT_INDEX	0xff000000
 
+
 /* Compute Express Link (CXL r3.1, sec 8.1.5) */
 #define PCI_DVSEC_CXL_PORT				3
 #define PCI_DVSEC_CXL_PORT_CTL				0x0c
 #define PCI_DVSEC_CXL_PORT_CTL_UNMASK_SBR		0x00000001
 
+/* Integrity and Data Encryption Extended Capability */
+#define PCI_IDE_CAP		0x4
+#define  PCI_IDE_CAP_LINK_IDE_SUPP	0x1	/* Link IDE Stream Supported */
+#define  PCI_IDE_CAP_SELECTIVE_IDE_SUPP 0x2	/* Selective IDE Streams Supported */
+#define  PCI_IDE_CAP_FLOWTHROUGH_IDE_SUPP 0x4	/* Flow-Through IDE Stream Supported */
+#define  PCI_IDE_CAP_PARTIAL_HEADER_ENC_SUPP 0x8 /* Partial Header Encryption Supported */
+#define  PCI_IDE_CAP_AGGREGATION_SUPP	0x10	/* Aggregation Supported */
+#define  PCI_IDE_CAP_PCRC_SUPP		0x20	/* PCRC Supported */
+#define  PCI_IDE_CAP_IDE_KM_SUPP	0x40	/* IDE_KM Protocol Supported */
+#define  PCI_IDE_CAP_ALG(x)	(((x) >> 8) & 0x1f) /* Supported Algorithms */
+#define  PCI_IDE_CAP_ALG_AES_GCM_256	0	/* AES-GCM 256 key size, 96b MAC */
+#define  PCI_IDE_CAP_LINK_TC_NUM(x)		(((x) >> 13) & 0x7) /* Link IDE TCs */
+#define  PCI_IDE_CAP_SELECTIVE_STREAMS_NUM(x)	(((x) >> 16) & 0xff) /* Selective IDE Streams */
+#define  PCI_IDE_CAP_TEE_LIMITED_SUPP   0x1000000 /* TEE-Limited Stream Supported */
+#define PCI_IDE_CTL		0x8
+#define  PCI_IDE_CTL_FLOWTHROUGH_IDE	0x4	/* Flow-Through IDE Stream Enabled */
+#define PCI_IDE_LINK_STREAM		0xC
+/* Link IDE Stream block, up to PCI_IDE_CAP_LINK_TC_NUM */
+/* Link IDE Stream Control Register */
+#define  PCI_IDE_LINK_CTL_EN		0x1	/* Link IDE Stream Enable */
+#define  PCI_IDE_LINK_CTL_TX_AGGR_NPR(x)(((x) >> 2) & 0x3) /* Tx Aggregation Mode NPR */
+#define  PCI_IDE_LINK_CTL_TX_AGGR_PR(x)	(((x) >> 4) & 0x3) /* Tx Aggregation Mode PR */
+#define  PCI_IDE_LINK_CTL_TX_AGGR_CPL(x)(((x) >> 6) & 0x3) /* Tx Aggregation Mode CPL */
+#define  PCI_IDE_LINK_CTL_PCRC_EN	0x100	/* PCRC Enable */
+#define  PCI_IDE_LINK_CTL_PART_ENC(x)	(((x) >> 10) & 0xf)  /* Partial Header Encryption Mode */
+#define  PCI_IDE_LINK_CTL_ALG(x)	(((x) >> 14) & 0x1f) /* Selected Algorithm */
+#define  PCI_IDE_LINK_CTL_TC(x)		(((x) >> 19) & 0x7)  /* Traffic Class */
+#define  PCI_IDE_LINK_CTL_ID(x)		(((x) >> 24) & 0xff) /* Stream ID */
+#define  PCI_IDE_LINK_CTL_ID_MASK	0xff000000
+
+/* Link IDE Stream Status Register */
+#define  PCI_IDE_LINK_STS_STATUS(x)	((x) & 0xf) /* Link IDE Stream State */
+#define  PCI_IDE_LINK_STS_RECVD_INTEGRITY_CHECK	0x80000000 /* Received Integrity Check Fail Msg */
+/* Selective IDE Stream block, up to PCI_IDE_CAP_SELECTIVE_STREAMS_NUM */
+/* Selective IDE Stream Capability Register */
+#define  PCI_IDE_SEL_CAP_BLOCKS_NUM(x)	((x) & 0xf) /*Address Association Register Blocks Number */
+/* Selective IDE Stream Control Register */
+#define  PCI_IDE_SEL_CTL_EN		0x1	/* Selective IDE Stream Enable */
+#define  PCI_IDE_SEL_CTL_TX_AGGR_NPR(x)	(((x) >> 2) & 0x3) /* Tx Aggregation Mode NPR */
+#define  PCI_IDE_SEL_CTL_TX_AGGR_PR(x)	(((x) >> 4) & 0x3) /* Tx Aggregation Mode PR */
+#define  PCI_IDE_SEL_CTL_TX_AGGR_CPL(x)	(((x) >> 6) & 0x3) /* Tx Aggregation Mode CPL */
+#define  PCI_IDE_SEL_CTL_PCRC_EN	0x100	/* PCRC Enable */
+#define  PCI_IDE_SEL_CTL_CFG_EN		0x200	/* Selective IDE for Configuration Requests */
+#define  PCI_IDE_SEL_CTL_PART_ENC(x)	(((x) >> 10) & 0xf)  /* Partial Header Encryption Mode */
+#define  PCI_IDE_SEL_CTL_ALG(x)		(((x) >> 14) & 0x1f) /* Selected Algorithm */
+#define  PCI_IDE_SEL_CTL_TC(x)		(((x) >> 19) & 0x7)  /* Traffic Class */
+#define  PCI_IDE_SEL_CTL_DEFAULT	0x400000 /* Default Stream */
+#define  PCI_IDE_SEL_CTL_TEE_LIMITED	(1 << 23) /* TEE-Limited Stream */
+#define  PCI_IDE_SEL_CTL_ID(x)		(((x) >> 24) & 0xff) /* Stream ID */
+/* Selective IDE Stream Status Register */
+#define  PCI_IDE_SEL_STS_STATUS(x)	((x) & 0xf) /* Selective IDE Stream State */
+#define  PCI_IDE_SEL_STS_RECVD_INTEGRITY_CHECK	0x80000000 /* Received Integrity Check Fail Msg */
+/* IDE RID Association Register 1 */
+#define  PCI_IDE_SEL_RID_1_LIMIT(x)	(((x) >> 8) & 0xffff) /* RID Limit */
+#define  PCI_IDE_SEL_RID_1(rid_limit)	(((rid_limit) & 0xffff) << 8)
+/* IDE RID Association Register 2 */
+#define  PCI_IDE_SEL_RID_2_VALID	0x1	/* Valid */
+#define  PCI_IDE_SEL_RID_2_BASE(x)	(((x) >> 8) & 0xffff) /* RID Base */
+#define  PCI_IDE_SEL_RID_2_SEG_BASE(x)	(((x) >> 24) & 0xff) /* Segmeng Base */
+#define  PCI_IDE_SEL_RID_2(v, rid_base, seg_base) ((((seg_base) & 0xff) << 24) | \
+						   (((rid_base) & 0xffff) << 8) | ((v) ? 1 : 0))
+/* Selective IDE Address Association Register Block, up to PCI_IDE_SEL_CAP_BLOCKS_NUM */
+#define  PCI_IDE_SEL_ADDR_1_VALID	0x1	/* Valid */
+#define  PCI_IDE_SEL_ADDR_1_BASE_LOW(x)	(((x) >> 8) & 0xfff) /* Memory Base Lower */
+#define  PCI_IDE_SEL_ADDR_1_LIMIT_LOW(x)(((x) >> 20) & 0xfff) /* Memory Limit Lower */
+/* IDE Address Association Register 2 is "Memory Limit Upper" */
+/* IDE Address Association Register 3 is "Memory Base Upper" */
+#define  PCI_IDE_SEL_ADDR_1(v, base, limit) ((FIELD_GET(0xfff00000, (limit))  << 20) | \
+					     (FIELD_GET(0xfff00000, (base)) << 8) | ((v) ? 1 : 0))
+#define  PCI_IDE_SEL_ADDR_2(limit)	((limit) >> 32)
+#define  PCI_IDE_SEL_ADDR_3(base)	((base) >> 32)
+
 #endif /* LINUX_PCI_REGS_H */
diff --git a/drivers/pci/ide.c b/drivers/pci/ide.c
new file mode 100644
index 000000000000..dc0632e836e7
--- /dev/null
+++ b/drivers/pci/ide.c
@@ -0,0 +1,186 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Integrity & Data Encryption (IDE)
+ *	PCIe r6.0, sec 6.33 DOE
+ */
+
+#define dev_fmt(fmt) "IDE: " fmt
+
+#include <linux/pci.h>
+#include <linux/pci-ide.h>
+#include <linux/bitfield.h>
+#include <linux/module.h>
+
+#define DRIVER_VERSION	"0.1"
+#define DRIVER_AUTHOR	"aik@amd.com"
+#define DRIVER_DESC	"Integrity and Data Encryption driver"
+
+/* Returns an offset of the specific IDE stream block */
+static u16 sel_off(struct pci_dev *pdev, unsigned int sel_index)
+{
+	u16 offset = pci_find_next_ext_capability(pdev, 0, PCI_EXT_CAP_ID_IDE);
+	unsigned int linknum = 0, selnum = 0, i;
+	u16 seloff;
+	u32 cap = 0;
+
+	if (!offset)
+		return 0;
+
+	pci_read_config_dword(pdev, offset + PCI_IDE_CAP, &cap);
+	if (cap & PCI_IDE_CAP_SELECTIVE_IDE_SUPP)
+		selnum = PCI_IDE_CAP_SELECTIVE_STREAMS_NUM(cap) + 1;
+
+	if (!selnum || sel_index >= selnum)
+		return 0;
+
+	if (cap & PCI_IDE_CAP_LINK_IDE_SUPP)
+		linknum = PCI_IDE_CAP_LINK_TC_NUM(cap) + 1;
+
+	seloff = offset + PCI_IDE_LINK_STREAM + linknum * 2 * 4;
+	for (i = 0; i < sel_index; ++i) {
+		u32 selcap = 0;
+
+		pci_read_config_dword(pdev, seloff, &selcap);
+
+		/* Selective Cap+Ctrl+Sta + Addr#*8 */
+		seloff += 3 * 4 + PCI_IDE_SEL_CAP_BLOCKS_NUM(selcap) * 2 * 4;
+	}
+
+	return seloff;
+}
+
+static u16 sel_off_addr_block(struct pci_dev *pdev, u16 offset, unsigned int blocknum)
+{
+	unsigned int blocks;
+	u32 selcap = 0;
+
+	pci_read_config_dword(pdev, offset, &selcap);
+
+	blocks = PCI_IDE_SEL_CAP_BLOCKS_NUM(selcap);
+	if (!blocks)
+		return 0;
+
+	return offset + 3 * 4 + // Skip Cap, Ctl, Sta
+		2 * 4 + // RID Association Register 1 and 2
+		blocknum * 3 * 4; // Each block is Address Association Register 1, 2, 3
+}
+
+static int set_sel(struct pci_dev *pdev, unsigned int sel_index, u32 value)
+{
+	u16 offset = sel_off(pdev, sel_index);
+	u32 status = 0;
+
+	if (!offset)
+		return -EINVAL;
+
+	pci_read_config_dword(pdev, offset + 8, &status);
+	if (status & PCI_IDE_SEL_STS_RECVD_INTEGRITY_CHECK) {
+		pci_warn(pdev, "[%x] Clearing \"Received integrity check\"\n", offset + 4);
+		pci_write_config_dword(pdev, offset + 8,
+				       status & ~PCI_IDE_SEL_STS_RECVD_INTEGRITY_CHECK);
+	}
+
+	/* Selective IDE Stream Control Register */
+	pci_write_config_dword(pdev, offset + 4, value);
+	return 0;
+}
+
+int pci_ide_set_sel(struct pci_dev *pdev, unsigned int sel_index, unsigned int streamid,
+		    bool enable, bool def, bool tee_limited, bool ide_cfg)
+{
+	return set_sel(pdev, sel_index,
+		       FIELD_PREP(PCI_IDE_LINK_CTL_ID_MASK, streamid) |
+		       (def ? PCI_IDE_SEL_CTL_DEFAULT : 0) |
+		       (enable ? PCI_IDE_SEL_CTL_EN : 0) |
+		       (tee_limited ? PCI_IDE_SEL_CTL_TEE_LIMITED : 0) |
+		       (ide_cfg ? PCI_IDE_SEL_CTL_CFG_EN : 0)
+		      );
+}
+EXPORT_SYMBOL_GPL(pci_ide_set_sel);
+
+int pci_ide_set_sel_rid_assoc(struct pci_dev *pdev, unsigned int sel_index,
+			      bool valid, u8 seg_base, u16 rid_base, u16 rid_limit)
+{
+	u16 offset = sel_off(pdev, sel_index);
+	u32 rid1 = PCI_IDE_SEL_RID_1(rid_limit);
+	u32 rid2 = PCI_IDE_SEL_RID_2(valid, rid_base, seg_base);
+	u32 ctl = 0;
+
+	if (!offset)
+		return -EINVAL;
+
+	pci_read_config_dword(pdev, offset + 4, &ctl);
+	if (ctl & PCI_IDE_SEL_CTL_EN)
+		pci_warn(pdev, "Setting RID when En=off triggers Integrity Check Fail Message");
+
+	/* IDE RID Association Register 1 */
+	pci_write_config_dword(pdev, offset + 0xC, rid1);
+	/* IDE RID Association Register 2 */
+	pci_write_config_dword(pdev, offset + 0x10, rid2);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(pci_ide_set_sel_rid_assoc);
+
+int pci_ide_set_sel_addr_assoc(struct pci_dev *pdev, unsigned int sel_index, unsigned int blocknum,
+			       bool valid, u64 base, u64 limit)
+{
+	u16 offset = sel_off(pdev, sel_index), offset_ab;
+	u32 a1 = PCI_IDE_SEL_ADDR_1(1, base, limit);
+	u32 a2 = PCI_IDE_SEL_ADDR_2(limit);
+	u32 a3 = PCI_IDE_SEL_ADDR_3(base);
+
+	if (!offset)
+		return -EINVAL;
+
+	offset_ab = sel_off_addr_block(pdev, offset, blocknum);
+	if (!offset_ab || offset_ab <= offset)
+		return -EINVAL;
+
+	/* IDE Address Association Register 1 */
+	pci_write_config_dword(pdev, offset_ab, a1);
+	/* IDE Address Association Register 2 */
+	pci_write_config_dword(pdev, offset_ab + 4, a2);
+	/* IDE Address Association Register 1 */
+	pci_write_config_dword(pdev, offset_ab + 8, a3);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(pci_ide_set_sel_addr_assoc);
+
+int pci_ide_get_sel_sta(struct pci_dev *pdev, unsigned int sel_index, u32 *status)
+{
+	u16 offset = sel_off(pdev, sel_index);
+	u32 s = 0;
+	int ret;
+
+	if (!offset)
+		return -EINVAL;
+
+
+	ret = pci_read_config_dword(pdev, offset + 8, &s);
+	if (ret)
+		return ret;
+
+	*status = s;
+	return 0;
+}
+EXPORT_SYMBOL_GPL(pci_ide_get_sel_sta);
+
+static int __init ide_init(void)
+{
+	int ret = 0;
+
+	pr_info(DRIVER_DESC " version: " DRIVER_VERSION "\n");
+	return ret;
+}
+
+static void __exit ide_cleanup(void)
+{
+}
+
+module_init(ide_init);
+module_exit(ide_cleanup);
+
+MODULE_VERSION(DRIVER_VERSION);
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR(DRIVER_AUTHOR);
+MODULE_DESCRIPTION(DRIVER_DESC);
diff --git a/drivers/pci/Kconfig b/drivers/pci/Kconfig
index b0b14468ba5d..8e908d684c77 100644
--- a/drivers/pci/Kconfig
+++ b/drivers/pci/Kconfig
@@ -137,6 +137,10 @@ config PCI_CMA
 config PCI_DOE
 	bool
 
+config PCI_IDE
+	tristate
+	default m
+
 config PCI_ECAM
 	bool
 
-- 
2.45.2