xref: /openbmc/linux/drivers/gpu/drm/lima/lima_mmu.c (revision 9b93eb47)
1 // SPDX-License-Identifier: GPL-2.0 OR MIT
2 /* Copyright 2017-2019 Qiang Yu <yuq825@gmail.com> */
3 
4 #include <linux/interrupt.h>
5 #include <linux/iopoll.h>
6 #include <linux/device.h>
7 
8 #include "lima_device.h"
9 #include "lima_mmu.h"
10 #include "lima_vm.h"
11 #include "lima_object.h"
12 #include "lima_regs.h"
13 
14 #define mmu_write(reg, data) writel(data, ip->iomem + reg)
15 #define mmu_read(reg) readl(ip->iomem + reg)
16 
17 #define lima_mmu_send_command(cmd, addr, val, cond)	     \
18 ({							     \
19 	int __ret;					     \
20 							     \
21 	mmu_write(LIMA_MMU_COMMAND, cmd);		     \
22 	__ret = readl_poll_timeout(ip->iomem + (addr), val,  \
23 				  cond, 0, 100);	     \
24 	if (__ret)					     \
25 		dev_err(dev->dev,			     \
26 			"mmu command %x timeout\n", cmd);    \
27 	__ret;						     \
28 })
29 
30 static irqreturn_t lima_mmu_irq_handler(int irq, void *data)
31 {
32 	struct lima_ip *ip = data;
33 	struct lima_device *dev = ip->dev;
34 	u32 status = mmu_read(LIMA_MMU_INT_STATUS);
35 	struct lima_sched_pipe *pipe;
36 
37 	/* for shared irq case */
38 	if (!status)
39 		return IRQ_NONE;
40 
41 	if (status & LIMA_MMU_INT_PAGE_FAULT) {
42 		u32 fault = mmu_read(LIMA_MMU_PAGE_FAULT_ADDR);
43 
44 		dev_err(dev->dev, "mmu page fault at 0x%x from bus id %d of type %s on %s\n",
45 			fault, LIMA_MMU_STATUS_BUS_ID(status),
46 			status & LIMA_MMU_STATUS_PAGE_FAULT_IS_WRITE ? "write" : "read",
47 			lima_ip_name(ip));
48 	}
49 
50 	if (status & LIMA_MMU_INT_READ_BUS_ERROR)
51 		dev_err(dev->dev, "mmu %s irq bus error\n", lima_ip_name(ip));
52 
53 	/* mask all interrupts before resume */
54 	mmu_write(LIMA_MMU_INT_MASK, 0);
55 	mmu_write(LIMA_MMU_INT_CLEAR, status);
56 
57 	pipe = dev->pipe + (ip->id == lima_ip_gpmmu ? lima_pipe_gp : lima_pipe_pp);
58 	lima_sched_pipe_mmu_error(pipe);
59 
60 	return IRQ_HANDLED;
61 }
62 
63 int lima_mmu_init(struct lima_ip *ip)
64 {
65 	struct lima_device *dev = ip->dev;
66 	int err;
67 	u32 v;
68 
69 	if (ip->id == lima_ip_ppmmu_bcast)
70 		return 0;
71 
72 	mmu_write(LIMA_MMU_DTE_ADDR, 0xCAFEBABE);
73 	if (mmu_read(LIMA_MMU_DTE_ADDR) != 0xCAFEB000) {
74 		dev_err(dev->dev, "mmu %s dte write test fail\n", lima_ip_name(ip));
75 		return -EIO;
76 	}
77 
78 	mmu_write(LIMA_MMU_COMMAND, LIMA_MMU_COMMAND_HARD_RESET);
79 	err = lima_mmu_send_command(LIMA_MMU_COMMAND_HARD_RESET,
80 				    LIMA_MMU_DTE_ADDR, v, v == 0);
81 	if (err)
82 		return err;
83 
84 	err = devm_request_irq(dev->dev, ip->irq, lima_mmu_irq_handler,
85 			       IRQF_SHARED, lima_ip_name(ip), ip);
86 	if (err) {
87 		dev_err(dev->dev, "mmu %s fail to request irq\n", lima_ip_name(ip));
88 		return err;
89 	}
90 
91 	mmu_write(LIMA_MMU_INT_MASK, LIMA_MMU_INT_PAGE_FAULT | LIMA_MMU_INT_READ_BUS_ERROR);
92 	mmu_write(LIMA_MMU_DTE_ADDR, dev->empty_vm->pd.dma);
93 	return lima_mmu_send_command(LIMA_MMU_COMMAND_ENABLE_PAGING,
94 				     LIMA_MMU_STATUS, v,
95 				     v & LIMA_MMU_STATUS_PAGING_ENABLED);
96 }
97 
98 void lima_mmu_fini(struct lima_ip *ip)
99 {
100 
101 }
102 
103 void lima_mmu_switch_vm(struct lima_ip *ip, struct lima_vm *vm)
104 {
105 	struct lima_device *dev = ip->dev;
106 	u32 v;
107 
108 	lima_mmu_send_command(LIMA_MMU_COMMAND_ENABLE_STALL,
109 			      LIMA_MMU_STATUS, v,
110 			      v & LIMA_MMU_STATUS_STALL_ACTIVE);
111 
112 	if (vm)
113 		mmu_write(LIMA_MMU_DTE_ADDR, vm->pd.dma);
114 
115 	/* flush the TLB */
116 	mmu_write(LIMA_MMU_COMMAND, LIMA_MMU_COMMAND_ZAP_CACHE);
117 
118 	lima_mmu_send_command(LIMA_MMU_COMMAND_DISABLE_STALL,
119 			      LIMA_MMU_STATUS, v,
120 			      !(v & LIMA_MMU_STATUS_STALL_ACTIVE));
121 }
122 
123 void lima_mmu_page_fault_resume(struct lima_ip *ip)
124 {
125 	struct lima_device *dev = ip->dev;
126 	u32 status = mmu_read(LIMA_MMU_STATUS);
127 	u32 v;
128 
129 	if (status & LIMA_MMU_STATUS_PAGE_FAULT_ACTIVE) {
130 		dev_info(dev->dev, "mmu resume\n");
131 
132 		mmu_write(LIMA_MMU_INT_MASK, 0);
133 		mmu_write(LIMA_MMU_DTE_ADDR, 0xCAFEBABE);
134 		lima_mmu_send_command(LIMA_MMU_COMMAND_HARD_RESET,
135 				      LIMA_MMU_DTE_ADDR, v, v == 0);
136 		mmu_write(LIMA_MMU_INT_MASK, LIMA_MMU_INT_PAGE_FAULT | LIMA_MMU_INT_READ_BUS_ERROR);
137 		mmu_write(LIMA_MMU_DTE_ADDR, dev->empty_vm->pd.dma);
138 		lima_mmu_send_command(LIMA_MMU_COMMAND_ENABLE_PAGING,
139 				      LIMA_MMU_STATUS, v,
140 				      v & LIMA_MMU_STATUS_PAGING_ENABLED);
141 	}
142 }
143