core/pci: Support PCI slot

Every PCIE bridge port or PHB is expected to be bound with PCI slot
, to which various PCI slot's functionalities are attached (e.g. power,
link, reset). This supports PCI slot:

   * PCI slot is reprsented by "struct pci_slot".
   * "struct pci_slot_ops" represents the functions supported on the
     PCI slot. It's initialized by PCI slot core at the beginning and
     allowed to be overrided by platform partially or completely.
   * On PCI hot plugging event, the PCI devices behind the slot are
     enumarated. Device sub-tree is populated and sent to OS by OPAL
     message.
   * On PCI hot unplugging event, the PCI devices behind the slot are
     destroyed. Device sub-tree is removed and the slot is powered off.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Stewart Smith <stewart@linux.vnet.ibm.com>

1 files changed, 255 insertions, 0 deletions

diff --git a/include/pci-slot.h b/include/pci-slot.h
new file mode 100644
index 0000000..cf22432
--- /dev/null
+++ b/include/pci-slot.h
@@ -0,0 +1,255 @@
+/* Copyright 2013-2016 IBM Corp.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+ * implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef __PCI_SLOT_H
+#define __PCI_SLOT_H
+
+#include <opal.h>
+#include <device.h>
+#include <timebase.h>
+#include <timer.h>
+#include <ccan/list/list.h>
+
+/*
+ * PCI Slot Info: Wired Lane Values
+ *
+ * Values 0 to 6 match slot map 1005. In case of *any* change here
+ * make sure to keep the lxvpd.c parsing code in sync *and* the
+ * corresponding label strings in pci.c
+ */
+#define PCI_SLOT_WIRED_LANES_UNKNOWN	0x00
+#define PCI_SLOT_WIRED_LANES_PCIE_X1	0x01
+#define PCI_SLOT_WIRED_LANES_PCIE_X2	0x02
+#define PCI_SLOT_WIRED_LANES_PCIE_X4	0x03
+#define PCI_SLOT_WIRED_LANES_PCIE_X8	0x04
+#define PCI_SLOT_WIRED_LANES_PCIE_X16	0x05
+#define PCI_SLOT_WIRED_LANES_PCIE_X32	0x06
+#define PCI_SLOT_WIRED_LANES_PCIX_32	0x07
+#define PCI_SLOT_WIRED_LANES_PCIX_64	0x08
+
+/* PCI Slot Info: Bus Clock Values */
+#define PCI_SLOT_BUS_CLK_RESERVED	0x00
+#define PCI_SLOT_BUS_CLK_GEN_1		0x01
+#define PCI_SLOT_BUS_CLK_GEN_2		0x02
+#define PCI_SLOT_BUS_CLK_GEN_3		0x03
+
+/* PCI Slot Info: Connector Type Values */
+#define PCI_SLOT_CONNECTOR_PCIE_EMBED	0x00
+#define PCI_SLOT_CONNECTOR_PCIE_X1	0x01
+#define PCI_SLOT_CONNECTOR_PCIE_X2	0x02
+#define PCI_SLOT_CONNECTOR_PCIE_X4	0x03
+#define PCI_SLOT_CONNECTOR_PCIE_X8	0x04
+#define PCI_SLOT_CONNECTOR_PCIE_X16	0x05
+#define PCI_SLOT_CONNECTOR_PCIE_NS	0x0E	/* Non-Standard */
+
+/* PCI Slot Info: Card Description Values */
+#define PCI_SLOT_DESC_NON_STANDARD	0x00	/* Embed/Non-Standard       */
+#define PCI_SLOT_DESC_PCIE_FH_FL	0x00	/* Full Height, Full Length */
+#define PCI_SLOT_DESC_PCIE_FH_HL	0x01	/* Full Height, Half Length */
+#define PCI_SLOT_DESC_PCIE_HH_FL	0x02	/* Half Height, Full Length */
+#define PCI_SLOT_DESC_PCIE_HH_HL	0x03	/* Half Height, Half Length */
+
+/* PCI Slot Info: Mechanicals Values */
+#define PCI_SLOT_MECH_NONE		0x00
+#define PCI_SLOT_MECH_RIGHT		0x01
+#define PCI_SLOT_MECH_LEFT		0x02
+#define PCI_SLOT_MECH_RIGHT_LEFT	0x03
+
+/* PCI Slot Info: Power LED Control Values */
+#define PCI_SLOT_PWR_LED_CTL_NONE	0x00	/* No Control        */
+#define PCI_SLOT_PWR_LED_CTL_FSP	0x01	/* FSP Controlled    */
+#define PCI_SLOT_PWR_LED_CTL_KERNEL	0x02	/* Kernel Controlled */
+
+/* PCI Slot Info: ATTN LED Control Values */
+#define PCI_SLOT_ATTN_LED_CTL_NONE	0x00	/* No Control        */
+#define PCI_SLOT_ATTN_LED_CTL_FSP	0x01	/* FSP Controlled    */
+#define PCI_SLOT_ATTN_LED_CTL_KERNEL	0x02	/* Kernel Controlled */
+
+/* Attention LED */
+#define PCI_SLOT_ATTN_LED_OFF		0
+#define PCI_SLOT_ATTN_LED_ON		1
+#define PCI_SLOT_ATTN_LED_BLINK		2
+
+/* Power state */
+#define PCI_SLOT_POWER_OFF		0
+#define PCI_SLOT_POWER_ON		1
+
+/*
+ * We have hard and soft reset for slot. Hard reset requires
+ * power-off and then power-on, but soft reset only resets
+ * secondary bus.
+ */
+struct pci_slot;
+struct pci_slot_ops {
+	/* For slot management */
+	int64_t (*get_presence_state)(struct pci_slot *slot, uint8_t *val);
+	int64_t (*get_link_state)(struct pci_slot *slot, uint8_t *val);
+	int64_t (*get_power_state)(struct pci_slot *slot, uint8_t *val);
+	int64_t (*get_attention_state)(struct pci_slot *slot, uint8_t *val);
+	int64_t (*get_latch_state)(struct pci_slot *slot, uint8_t *val);
+	int64_t (*set_power_state)(struct pci_slot *slot, uint8_t val);
+	int64_t (*set_attention_state)(struct pci_slot *slot, uint8_t val);
+
+	/* SM based functions for reset */
+	void (*prepare_link_change)(struct pci_slot *slot, bool is_up);
+	int64_t (*poll_link)(struct pci_slot *slot);
+	int64_t (*creset)(struct pci_slot *slot);
+	int64_t (*freset)(struct pci_slot *slot);
+	int64_t (*pfreset)(struct pci_slot *slot);
+	int64_t (*hreset)(struct pci_slot *slot);
+	int64_t (*poll)(struct pci_slot *slot);
+
+	/* Auxillary functions */
+	void (*add_properties)(struct pci_slot *slot, struct dt_node *np);
+};
+
+/*
+ * The PCI slot state is split up into base and number. With this
+ * design, the individual platforms can introduce their own PCI
+ * slot states with addition to the base. Eventually, the base
+ * state can be recognized by PCI slot core.
+ */
+#define PCI_SLOT_STATE_MASK			0xFFFFFF00
+#define PCI_SLOT_STATE_NORMAL			0x00000000
+#define PCI_SLOT_STATE_LINK			0x00000100
+#define   PCI_SLOT_STATE_LINK_START_POLL	0x00000101
+#define   PCI_SLOT_STATE_LINK_DELAY_FINALIZED	0x00000102
+#define   PCI_SLOT_STATE_LINK_POLLING		0x00000103
+#define PCI_SLOT_STATE_HRESET			0x00000200
+#define   PCI_SLOT_STATE_HRESET_START		0x00000201
+#define   PCI_SLOT_STATE_HRESET_HOLD		0x00000202
+#define PCI_SLOT_STATE_FRESET			0x00000300
+#define   PCI_SLOT_STATE_FRESET_POWER_OFF	0x00000301
+#define PCI_SLOT_STATE_PFRESET			0x00000400
+#define   PCI_SLOT_STATE_PFRESET_START		0x00000401
+#define PCI_SLOT_STATE_CRESET			0x00000500
+#define   PCI_SLOT_STATE_CRESET_START		0x00000501
+#define PCI_SLOT_STATE_GPOWER			0x00000600
+#define   PCI_SLOT_STATE_GPOWER_START		0x00000601
+#define PCI_SLOT_STATE_SPOWER			0x00000700
+#define   PCI_SLOT_STATE_SPOWER_START		0x00000701
+#define   PCI_SLOT_STATE_SPOWER_DONE		0x00000702
+#define PCI_SLOT_STATE_GPRESENCE		0x00000800
+#define   PCI_SLOT_STATE_GPRESENCE_START	0x00000801
+
+
+struct pci_slot {
+	uint32_t		flags;
+#define PCI_SLOT_FLAG_BOOTUP		0x1
+
+	struct phb		*phb;
+	struct pci_device	*pd;
+
+	/* Identifier */
+	uint64_t		id;
+	struct timer		timer;
+	uint64_t		async_token;
+	uint8_t			power_state;
+
+	/* Slot information */
+	uint8_t			pluggable;
+	uint8_t			power_ctl;
+	uint8_t			power_led_ctl;
+	uint8_t			attn_led_ctl;
+	uint8_t			connector_type;
+	uint8_t			card_desc;
+	uint8_t			card_mech;
+	uint8_t			wired_lanes;
+
+	/*
+	 * PCI slot is driven by state machine with polling function.
+	 * @delay_tgt_tb tracks the current delay while @retries has
+	 * the left rounds of delays. They should be set prior to
+	 * switching next PCI slot state and changed (decreased)
+	 * accordingly in the polling function.
+	 */
+	uint32_t		state;
+	uint32_t		retry_state;
+	uint32_t		link_cap;
+	uint32_t		slot_cap;
+	uint64_t		delay_tgt_tb;
+	uint64_t		retries;
+	struct pci_slot_ops	ops;
+	void			*data;
+};
+
+#define PCI_SLOT_ID_PREFIX	0x8000000000000000
+#define PCI_SLOT_ID(phb, bdfn)	\
+	(PCI_SLOT_ID_PREFIX | ((uint64_t)(bdfn) << 16) | (phb)->opal_id)
+#define PCI_PHB_SLOT_ID(phb)	((phb)->opal_id)
+#define PCI_SLOT_PHB_INDEX(id)	((id) & 0xfffful)
+#define PCI_SLOT_BDFN(id)	(((id) >> 16) & 0xfffful)
+
+static inline uint32_t pci_slot_add_flags(struct pci_slot *slot,
+					  uint32_t flags)
+{
+	uint32_t old = 0;
+
+	if (slot) {
+		old = slot->flags;
+		slot->flags |= flags;
+	}
+
+	return old;
+}
+
+static inline bool pci_slot_has_flags(struct pci_slot *slot,
+				      uint32_t flags)
+{
+	if (!slot)
+		return false;
+
+	if ((slot->flags & flags) == flags)
+		return true;
+
+	return false;
+}
+
+static inline uint32_t pci_slot_remove_flags(struct pci_slot *slot,
+					     uint32_t flags)
+{
+	uint32_t old = 0;
+
+	if (slot) {
+		old = slot->flags;
+		slot->flags &= ~flags;
+	}
+
+	return old;
+}
+
+static inline void pci_slot_set_state(struct pci_slot *slot, uint32_t state)
+{
+	if (slot)
+		slot->state = state;
+}
+
+static inline uint64_t pci_slot_set_sm_timeout(struct pci_slot *slot,
+					       uint64_t dur)
+{
+	if (slot)
+		slot->delay_tgt_tb = mftb() + dur;
+	return dur;
+}
+
+extern struct pci_slot *pci_slot_alloc(struct phb *phb,
+				       struct pci_device *pd);
+extern struct pci_slot *pcie_slot_create(struct phb *phb,
+					 struct pci_device *pd);
+extern void pci_slot_add_dt_properties(struct pci_slot *slot,
+				       struct dt_node *np);
+extern struct pci_slot *pci_slot_find(uint64_t id);
+#endif /* __PCI_SLOT_H */