1 // SPDX-License-Identifier: (BSD-3-Clause OR GPL-2.0-only)
2 /* Copyright(c) 2021 Intel Corporation */
3 #include <linux/iopoll.h>
4 #include <linux/mutex.h>
5 #include <linux/types.h>
6 #include "adf_accel_devices.h"
7 #include "adf_common_drv.h"
8 #include "adf_gen4_pfvf.h"
9 #include "adf_pfvf_pf_proto.h"
10 #include "adf_pfvf_utils.h"
11 
12 #define ADF_4XXX_PF2VM_OFFSET(i)	(0x40B010 + ((i) * 0x20))
13 #define ADF_4XXX_VM2PF_OFFSET(i)	(0x40B014 + ((i) * 0x20))
14 
15 /* VF2PF interrupt source registers */
16 #define ADF_4XXX_VM2PF_SOU		0x41A180
17 #define ADF_4XXX_VM2PF_MSK		0x41A1C0
18 #define ADF_GEN4_VF_MSK			0xFFFF
19 
20 #define ADF_PFVF_GEN4_MSGTYPE_SHIFT	2
21 #define ADF_PFVF_GEN4_MSGTYPE_MASK	0x3F
22 #define ADF_PFVF_GEN4_MSGDATA_SHIFT	8
23 #define ADF_PFVF_GEN4_MSGDATA_MASK	0xFFFFFF
24 
25 static const struct pfvf_csr_format csr_gen4_fmt = {
26 	{ ADF_PFVF_GEN4_MSGTYPE_SHIFT, ADF_PFVF_GEN4_MSGTYPE_MASK },
27 	{ ADF_PFVF_GEN4_MSGDATA_SHIFT, ADF_PFVF_GEN4_MSGDATA_MASK },
28 };
29 
30 static u32 adf_gen4_pf_get_pf2vf_offset(u32 i)
31 {
32 	return ADF_4XXX_PF2VM_OFFSET(i);
33 }
34 
35 static u32 adf_gen4_pf_get_vf2pf_offset(u32 i)
36 {
37 	return ADF_4XXX_VM2PF_OFFSET(i);
38 }
39 
40 static void adf_gen4_enable_vf2pf_interrupts(void __iomem *pmisc_addr, u32 vf_mask)
41 {
42 	u32 val;
43 
44 	val = ADF_CSR_RD(pmisc_addr, ADF_4XXX_VM2PF_MSK) & ~vf_mask;
45 	ADF_CSR_WR(pmisc_addr, ADF_4XXX_VM2PF_MSK, val);
46 }
47 
48 static void adf_gen4_disable_all_vf2pf_interrupts(void __iomem *pmisc_addr)
49 {
50 	ADF_CSR_WR(pmisc_addr, ADF_4XXX_VM2PF_MSK, ADF_GEN4_VF_MSK);
51 }
52 
53 static u32 adf_gen4_disable_pending_vf2pf_interrupts(void __iomem *pmisc_addr)
54 {
55 	u32 sources, disabled, pending;
56 
57 	/* Get the interrupt sources triggered by VFs */
58 	sources = ADF_CSR_RD(pmisc_addr, ADF_4XXX_VM2PF_SOU);
59 	if (!sources)
60 		return 0;
61 
62 	/* Get the already disabled interrupts */
63 	disabled = ADF_CSR_RD(pmisc_addr, ADF_4XXX_VM2PF_MSK);
64 
65 	pending = sources & ~disabled;
66 	if (!pending)
67 		return 0;
68 
69 	/* Due to HW limitations, when disabling the interrupts, we can't
70 	 * just disable the requested sources, as this would lead to missed
71 	 * interrupts if VM2PF_SOU changes just before writing to VM2PF_MSK.
72 	 * To work around it, disable all and re-enable only the sources that
73 	 * are not in vf_mask and were not already disabled. Re-enabling will
74 	 * trigger a new interrupt for the sources that have changed in the
75 	 * meantime, if any.
76 	 */
77 	ADF_CSR_WR(pmisc_addr, ADF_4XXX_VM2PF_MSK, ADF_GEN4_VF_MSK);
78 	ADF_CSR_WR(pmisc_addr, ADF_4XXX_VM2PF_MSK, disabled | sources);
79 
80 	/* Return the sources of the (new) interrupt(s) */
81 	return pending;
82 }
83 
84 static int adf_gen4_pfvf_send(struct adf_accel_dev *accel_dev,
85 			      struct pfvf_message msg, u32 pfvf_offset,
86 			      struct mutex *csr_lock)
87 {
88 	void __iomem *pmisc_addr = adf_get_pmisc_base(accel_dev);
89 	u32 csr_val;
90 	int ret;
91 
92 	csr_val = adf_pfvf_csr_msg_of(accel_dev, msg, &csr_gen4_fmt);
93 	if (unlikely(!csr_val))
94 		return -EINVAL;
95 
96 	mutex_lock(csr_lock);
97 
98 	ADF_CSR_WR(pmisc_addr, pfvf_offset, csr_val | ADF_PFVF_INT);
99 
100 	/* Wait for confirmation from remote that it received the message */
101 	ret = read_poll_timeout(ADF_CSR_RD, csr_val, !(csr_val & ADF_PFVF_INT),
102 				ADF_PFVF_MSG_ACK_DELAY_US,
103 				ADF_PFVF_MSG_ACK_MAX_DELAY_US,
104 				true, pmisc_addr, pfvf_offset);
105 	if (ret < 0)
106 		dev_dbg(&GET_DEV(accel_dev), "ACK not received from remote\n");
107 
108 	mutex_unlock(csr_lock);
109 	return ret;
110 }
111 
112 static struct pfvf_message adf_gen4_pfvf_recv(struct adf_accel_dev *accel_dev,
113 					      u32 pfvf_offset, u8 compat_ver)
114 {
115 	void __iomem *pmisc_addr = adf_get_pmisc_base(accel_dev);
116 	struct pfvf_message msg = { 0 };
117 	u32 csr_val;
118 
119 	/* Read message from the CSR */
120 	csr_val = ADF_CSR_RD(pmisc_addr, pfvf_offset);
121 	if (!(csr_val & ADF_PFVF_INT)) {
122 		dev_info(&GET_DEV(accel_dev),
123 			 "Spurious PFVF interrupt, msg 0x%.8x. Ignored\n", csr_val);
124 		return msg;
125 	}
126 
127 	/* We can now acknowledge the message reception by clearing the
128 	 * interrupt bit
129 	 */
130 	ADF_CSR_WR(pmisc_addr, pfvf_offset, csr_val & ~ADF_PFVF_INT);
131 
132 	/* Return the pfvf_message format */
133 	return adf_pfvf_message_of(accel_dev, csr_val, &csr_gen4_fmt);
134 }
135 
136 void adf_gen4_init_pf_pfvf_ops(struct adf_pfvf_ops *pfvf_ops)
137 {
138 	pfvf_ops->enable_comms = adf_enable_pf2vf_comms;
139 	pfvf_ops->get_pf2vf_offset = adf_gen4_pf_get_pf2vf_offset;
140 	pfvf_ops->get_vf2pf_offset = adf_gen4_pf_get_vf2pf_offset;
141 	pfvf_ops->enable_vf2pf_interrupts = adf_gen4_enable_vf2pf_interrupts;
142 	pfvf_ops->disable_all_vf2pf_interrupts = adf_gen4_disable_all_vf2pf_interrupts;
143 	pfvf_ops->disable_pending_vf2pf_interrupts = adf_gen4_disable_pending_vf2pf_interrupts;
144 	pfvf_ops->send_msg = adf_gen4_pfvf_send;
145 	pfvf_ops->recv_msg = adf_gen4_pfvf_recv;
146 }
147 EXPORT_SYMBOL_GPL(adf_gen4_init_pf_pfvf_ops);
148