[RFC PATCH v2 02/22] PCI/IDE: Fixes to make it work on AMD SNP-SEV

[Alexey Kardashevskiy <aik@amd.com>]

The IDE proposed patches do setup of endpoints while they should focus
on root port.

These are workarounds better be discussed in
"[PATCH 00/11] PCI/TSM: Core infrastructure for PCI device security
(TDISP)"

Signed-off-by: Alexey Kardashevskiy <aik@amd.com>
---
 include/linux/pci-ide.h       | 19 +++--
 include/uapi/linux/pci_regs.h |  4 +-
 drivers/pci/ide.c             | 76 ++++++++++++++++----
 3 files changed, 78 insertions(+), 21 deletions(-)

diff --git a/include/linux/pci-ide.h b/include/linux/pci-ide.h
index 24e08a413645..f784fb16cc88 100644
--- a/include/linux/pci-ide.h
+++ b/include/linux/pci-ide.h
@@ -8,26 +8,33 @@
 
 #include <linux/range.h>
 
+enum pci_ide_flags {
+	PCI_IDE_SETUP_ROOT_PORT = BIT(0),
+	PCI_IDE_SETUP_ROOT_PORT_MEM = BIT(1),
+};
+
 struct pci_ide {
 	int domain;
 	u16 devid_start;
 	u16 devid_end;
+	u16 rpid_start;
+	u16 rpid_end;
 	int stream_id;
 	const char *name;
 	int nr_mem;
 	struct range mem[16];
+	unsigned int dev_sel_ctl;
+	unsigned int rootport_sel_ctl;
+	enum pci_ide_flags flags;
 };
 
 void pci_ide_stream_probe(struct pci_dev *pdev, struct pci_ide *ide);
 
-enum pci_ide_flags {
-	PCI_IDE_SETUP_ROOT_PORT = BIT(0),
-};
-
 int pci_ide_stream_setup(struct pci_dev *pdev, struct pci_ide *ide,
 			 enum pci_ide_flags flags);
-void pci_ide_stream_teardown(struct pci_dev *pdev, struct pci_ide *ide,
-			     enum pci_ide_flags flags);
+void pci_ide_stream_teardown(struct pci_dev *pdev, struct pci_ide *ide);
 void pci_ide_enable_stream(struct pci_dev *pdev, struct pci_ide *ide);
 void pci_ide_disable_stream(struct pci_dev *pdev, struct pci_ide *ide);
+int pci_ide_stream_state(struct pci_dev *pdev, struct pci_ide *ide, u32 *status, u32 *rpstatus);
+
 #endif /* __PCI_IDE_H__ */
diff --git a/include/uapi/linux/pci_regs.h b/include/uapi/linux/pci_regs.h
index 498c6b298186..15bd8e2b3cf5 100644
--- a/include/uapi/linux/pci_regs.h
+++ b/include/uapi/linux/pci_regs.h
@@ -1293,9 +1293,9 @@
 /* Selective IDE Address Association Register Block, up to PCI_IDE_SEL_CAP_ASSOC_NUM */
 #define  PCI_IDE_SEL_ADDR_1(x)			(20 + (x) * 12)
 #define   PCI_IDE_SEL_ADDR_1_VALID		0x1
-#define   PCI_IDE_SEL_ADDR_1_BASE_LOW_MASK	0x000fff0
+#define   PCI_IDE_SEL_ADDR_1_BASE_LOW_MASK	0x000fff00
 #define   PCI_IDE_SEL_ADDR_1_BASE_LOW_SHIFT	20
-#define   PCI_IDE_SEL_ADDR_1_LIMIT_LOW_MASK 	0xfff0000
+#define   PCI_IDE_SEL_ADDR_1_LIMIT_LOW_MASK	0xfff00000
 #define   PCI_IDE_SEL_ADDR_1_LIMIT_LOW_SHIFT	20
 /* IDE Address Association Register 2 is "Memory Limit Upper" */
 /* IDE Address Association Register 3 is "Memory Base Upper" */
diff --git a/drivers/pci/ide.c b/drivers/pci/ide.c
index 500b63e149cf..3c53b27f8447 100644
--- a/drivers/pci/ide.c
+++ b/drivers/pci/ide.c
@@ -50,10 +50,10 @@ void pci_ide_init(struct pci_dev *pdev)
 	else
 		sel_ide_cap = ide_cap + PCI_IDE_LINK_STREAM;
 
-	for (int i = 0; i < PCI_IDE_CAP_SELECTIVE_STREAMS_NUM(val); i++) {
+	for (int i = 0; i < PCI_IDE_CAP_SELECTIVE_STREAMS_NUM(val) + 1; i++) {
 		if (i == 0) {
 			pci_read_config_dword(pdev, sel_ide_cap, &val);
-			nr_ide_mem = PCI_IDE_SEL_CAP_ASSOC_NUM(val);
+			nr_ide_mem = PCI_IDE_SEL_CAP_ASSOC_NUM(val) + 1;
 		} else {
 			int offset = sel_ide_offset(sel_ide_cap, i, nr_ide_mem);
 
@@ -118,7 +118,7 @@ void pci_set_nr_ide_streams(struct pci_host_bridge *hb, int nr)
 	hb->nr_ide_streams = nr;
 	sysfs_update_group(&hb->dev.kobj, &pci_ide_attr_group);
 }
-EXPORT_SYMBOL_NS_GPL(pci_set_nr_ide_streams, PCI_IDE);
+EXPORT_SYMBOL_NS_GPL(pci_set_nr_ide_streams, "PCI_IDE");
 
 void pci_init_host_bridge_ide(struct pci_host_bridge *hb)
 {
@@ -148,6 +148,10 @@ void pci_ide_stream_probe(struct pci_dev *pdev, struct pci_ide *ide)
 	else
 		ide->devid_end = ide->devid_start;
 
+	/* Enable everything into the rootport by default */
+	ide->rpid_start = 0;
+	ide->rpid_end = 0xffff;
+
 	/* TODO: address association probing... */
 }
 EXPORT_SYMBOL_GPL(pci_ide_stream_probe);
@@ -160,7 +164,7 @@ static void __pci_ide_stream_teardown(struct pci_dev *pdev, struct pci_ide *ide)
 			     pdev->nr_ide_mem);
 
 	pci_write_config_dword(pdev, pos + PCI_IDE_SEL_CTL, 0);
-	for (int i = ide->nr_mem - 1; i >= 0; i--) {
+	for (int i = min(ide->nr_mem, pdev->nr_ide_mem) - 1; i >= 0; i--) {
 		pci_write_config_dword(pdev, pos + PCI_IDE_SEL_ADDR_3(i), 0);
 		pci_write_config_dword(pdev, pos + PCI_IDE_SEL_ADDR_2(i), 0);
 		pci_write_config_dword(pdev, pos + PCI_IDE_SEL_ADDR_1(i), 0);
@@ -169,7 +173,7 @@ static void __pci_ide_stream_teardown(struct pci_dev *pdev, struct pci_ide *ide)
         pci_write_config_dword(pdev, pos + PCI_IDE_SEL_RID_1, 0);
 }
 
-static void __pci_ide_stream_setup(struct pci_dev *pdev, struct pci_ide *ide)
+static int __pci_ide_stream_setup(struct pci_dev *pdev, struct pci_ide *ide, bool mem, bool rp)
 {
 	int pos;
 	u32 val;
@@ -177,14 +181,20 @@ static void __pci_ide_stream_setup(struct pci_dev *pdev, struct pci_ide *ide)
 	pos = sel_ide_offset(pdev->sel_ide_cap, ide->stream_id,
 			     pdev->nr_ide_mem);
 
-	val = FIELD_PREP(PCI_IDE_SEL_RID_1_LIMIT_MASK, ide->devid_end);
+	val = FIELD_PREP(PCI_IDE_SEL_RID_1_LIMIT_MASK, rp ? ide->rpid_end : ide->devid_end);
 	pci_write_config_dword(pdev, pos + PCI_IDE_SEL_RID_1, val);
 
 	val = FIELD_PREP(PCI_IDE_SEL_RID_2_VALID, 1) |
-	      FIELD_PREP(PCI_IDE_SEL_RID_2_BASE_MASK, ide->devid_start) |
+	      FIELD_PREP(PCI_IDE_SEL_RID_2_BASE_MASK, rp ? ide->rpid_start : ide->devid_start) |
 	      FIELD_PREP(PCI_IDE_SEL_RID_2_SEG_MASK, ide->domain);
 	pci_write_config_dword(pdev, pos + PCI_IDE_SEL_RID_2, val);
 
+	if (!mem)
+		return 0;
+
+	if (ide->nr_mem > pdev->nr_ide_mem)
+		return -EINVAL;
+
 	for (int i = 0; i < ide->nr_mem; i++) {
 		val = FIELD_PREP(PCI_IDE_SEL_ADDR_1_VALID, 1) |
 		      FIELD_PREP(PCI_IDE_SEL_ADDR_1_BASE_LOW_MASK,
@@ -201,6 +211,8 @@ static void __pci_ide_stream_setup(struct pci_dev *pdev, struct pci_ide *ide)
 		val = upper_32_bits(ide->mem[i].start);
 		pci_write_config_dword(pdev, pos + PCI_IDE_SEL_ADDR_3(i), val);
 	}
+
+	return 0;
 }
 
 /*
@@ -248,10 +260,14 @@ int pci_ide_stream_setup(struct pci_dev *pdev, struct pci_ide *ide,
 			goto err;
 		}
 
-	__pci_ide_stream_setup(pdev, ide);
-	if (flags & PCI_IDE_SETUP_ROOT_PORT)
-		__pci_ide_stream_setup(rp, ide);
+	rc = __pci_ide_stream_setup(pdev, ide, true, false);
+	if (!rc && (flags & PCI_IDE_SETUP_ROOT_PORT))
+		rc = __pci_ide_stream_setup(rp, ide, !!(flags & PCI_IDE_SETUP_ROOT_PORT_MEM), true);
+
+	if (rc)
+		goto err;
 
+	ide->flags = flags;
 	return 0;
 err:
 	for (; mem >= 0; mem--)
@@ -268,6 +284,7 @@ EXPORT_SYMBOL_GPL(pci_ide_stream_setup);
 
 void pci_ide_enable_stream(struct pci_dev *pdev, struct pci_ide *ide)
 {
+	struct pci_dev *rp = pcie_find_root_port(pdev);
 	int pos;
 	u32 val;
 
@@ -276,14 +293,27 @@ void pci_ide_enable_stream(struct pci_dev *pdev, struct pci_ide *ide)
 
 	val = FIELD_PREP(PCI_IDE_SEL_CTL_ID_MASK, ide->stream_id) |
 	      FIELD_PREP(PCI_IDE_SEL_CTL_DEFAULT, 1);
+	val |= FIELD_PREP(PCI_IDE_SEL_CTL_EN, 1);
+	/* there is rootport and pdev is not it */
+	if (rp && rp != pdev)
+		val |= ide->dev_sel_ctl;
+	else
+		val |= ide->rootport_sel_ctl;
 	pci_write_config_dword(pdev, pos + PCI_IDE_SEL_CTL, val);
+
+	if (ide->flags & PCI_IDE_SETUP_ROOT_PORT && rp && rp != pdev)
+		pci_ide_enable_stream(rp, ide);
 }
 EXPORT_SYMBOL_GPL(pci_ide_enable_stream);
 
 void pci_ide_disable_stream(struct pci_dev *pdev, struct pci_ide *ide)
 {
+	struct pci_dev *rp = pcie_find_root_port(pdev);
 	int pos;
 
+	if (ide->flags & PCI_IDE_SETUP_ROOT_PORT && rp && rp != pdev)
+		pci_ide_disable_stream(rp, ide);
+
 	pos = sel_ide_offset(pdev->sel_ide_cap, ide->stream_id,
 			     pdev->nr_ide_mem);
 
@@ -291,14 +321,13 @@ void pci_ide_disable_stream(struct pci_dev *pdev, struct pci_ide *ide)
 }
 EXPORT_SYMBOL_GPL(pci_ide_disable_stream);
 
-void pci_ide_stream_teardown(struct pci_dev *pdev, struct pci_ide *ide,
-			     enum pci_ide_flags flags)
+void pci_ide_stream_teardown(struct pci_dev *pdev, struct pci_ide *ide)
 {
 	struct pci_host_bridge *hb = pci_find_host_bridge(pdev->bus);
 	struct pci_dev *rp = pcie_find_root_port(pdev);
 
 	__pci_ide_stream_teardown(pdev, ide);
-	if (flags & PCI_IDE_SETUP_ROOT_PORT)
+	if (ide->flags & PCI_IDE_SETUP_ROOT_PORT)
 		__pci_ide_stream_teardown(rp, ide);
 
 	for (int i = ide->nr_mem - 1; i >= 0; i--)
@@ -309,3 +338,24 @@ void pci_ide_stream_teardown(struct pci_dev *pdev, struct pci_ide *ide,
 	clear_bit_unlock(ide->stream_id, hb->ide_stream_ids);
 }
 EXPORT_SYMBOL_GPL(pci_ide_stream_teardown);
+
+static int __pci_ide_stream_state(struct pci_dev *pdev, struct pci_ide *ide, u32 *status)
+{
+	int pos = sel_ide_offset(pdev->sel_ide_cap, ide->stream_id,
+				 pdev->nr_ide_mem);
+
+	return pci_read_config_dword(pdev, pos + PCI_IDE_SEL_STS, status);
+}
+
+int pci_ide_stream_state(struct pci_dev *pdev, struct pci_ide *ide, u32 *status, u32 *rpstatus)
+{
+	int ret = __pci_ide_stream_state(pdev, ide, status);
+
+	if (!ret && ide->flags & PCI_IDE_SETUP_ROOT_PORT) {
+		struct pci_dev *rp = pcie_find_root_port(pdev);
+
+		ret = __pci_ide_stream_state(rp, ide, rpstatus);
+	}
+	return ret;
+}
+EXPORT_SYMBOL_GPL(pci_ide_stream_state);
-- 
2.47.1