xref: /linux/drivers/gpu/drm/imagination/pvr_vm_mips.c (revision 03c11eb3b16dc0058589751dfd91f254be2be613)
1 // SPDX-License-Identifier: GPL-2.0-only OR MIT
2 /* Copyright (c) 2023 Imagination Technologies Ltd. */
3 
4 #include "pvr_device.h"
5 #include "pvr_fw_mips.h"
6 #include "pvr_gem.h"
7 #include "pvr_mmu.h"
8 #include "pvr_rogue_mips.h"
9 #include "pvr_vm.h"
10 #include "pvr_vm_mips.h"
11 
12 #include <drm/drm_managed.h>
13 #include <linux/dma-mapping.h>
14 #include <linux/err.h>
15 #include <linux/slab.h>
16 #include <linux/types.h>
17 
18 /**
19  * pvr_vm_mips_init() - Initialise MIPS FW pagetable
20  * @pvr_dev: Target PowerVR device.
21  *
22  * Returns:
23  *  * 0 on success,
24  *  * -%EINVAL,
25  *  * Any error returned by pvr_gem_object_create(), or
26  *  * And error returned by pvr_gem_object_vmap().
27  */
28 int
29 pvr_vm_mips_init(struct pvr_device *pvr_dev)
30 {
31 	u32 pt_size = 1 << ROGUE_MIPSFW_LOG2_PAGETABLE_SIZE_4K(pvr_dev);
32 	struct device *dev = from_pvr_device(pvr_dev)->dev;
33 	struct pvr_fw_mips_data *mips_data;
34 	u32 phys_bus_width;
35 	int page_nr;
36 	int err;
37 
38 	/* Page table size must be at most ROGUE_MIPSFW_MAX_NUM_PAGETABLE_PAGES * 4k pages. */
39 	if (pt_size > ROGUE_MIPSFW_MAX_NUM_PAGETABLE_PAGES * SZ_4K)
40 		return -EINVAL;
41 
42 	if (PVR_FEATURE_VALUE(pvr_dev, phys_bus_width, &phys_bus_width))
43 		return -EINVAL;
44 
45 	mips_data = drmm_kzalloc(from_pvr_device(pvr_dev), sizeof(*mips_data), GFP_KERNEL);
46 	if (!mips_data)
47 		return -ENOMEM;
48 
49 	for (page_nr = 0; page_nr < ARRAY_SIZE(mips_data->pt_pages); page_nr++) {
50 		mips_data->pt_pages[page_nr] = alloc_page(GFP_KERNEL | __GFP_ZERO);
51 		if (!mips_data->pt_pages[page_nr]) {
52 			err = -ENOMEM;
53 			goto err_free_pages;
54 		}
55 
56 		mips_data->pt_dma_addr[page_nr] = dma_map_page(dev, mips_data->pt_pages[page_nr], 0,
57 							       PAGE_SIZE, DMA_TO_DEVICE);
58 		if (dma_mapping_error(dev, mips_data->pt_dma_addr[page_nr])) {
59 			err = -ENOMEM;
60 			__free_page(mips_data->pt_pages[page_nr]);
61 			goto err_free_pages;
62 		}
63 	}
64 
65 	mips_data->pt = vmap(mips_data->pt_pages, pt_size >> PAGE_SHIFT, VM_MAP,
66 			     pgprot_writecombine(PAGE_KERNEL));
67 	if (!mips_data->pt) {
68 		err = -ENOMEM;
69 		goto err_free_pages;
70 	}
71 
72 	mips_data->pfn_mask = (phys_bus_width > 32) ? ROGUE_MIPSFW_ENTRYLO_PFN_MASK_ABOVE_32BIT :
73 						      ROGUE_MIPSFW_ENTRYLO_PFN_MASK;
74 
75 	mips_data->cache_policy = (phys_bus_width > 32) ? ROGUE_MIPSFW_CACHED_POLICY_ABOVE_32BIT :
76 							  ROGUE_MIPSFW_CACHED_POLICY;
77 
78 	pvr_dev->fw_dev.processor_data.mips_data = mips_data;
79 
80 	return 0;
81 
82 err_free_pages:
83 	while (--page_nr >= 0) {
84 		dma_unmap_page(from_pvr_device(pvr_dev)->dev,
85 			       mips_data->pt_dma_addr[page_nr], PAGE_SIZE, DMA_TO_DEVICE);
86 
87 		__free_page(mips_data->pt_pages[page_nr]);
88 	}
89 
90 	return err;
91 }
92 
93 /**
94  * pvr_vm_mips_fini() - Release MIPS FW pagetable
95  * @pvr_dev: Target PowerVR device.
96  */
97 void
98 pvr_vm_mips_fini(struct pvr_device *pvr_dev)
99 {
100 	struct pvr_fw_device *fw_dev = &pvr_dev->fw_dev;
101 	struct pvr_fw_mips_data *mips_data = fw_dev->processor_data.mips_data;
102 	int page_nr;
103 
104 	vunmap(mips_data->pt);
105 	for (page_nr = ARRAY_SIZE(mips_data->pt_pages) - 1; page_nr >= 0; page_nr--) {
106 		dma_unmap_page(from_pvr_device(pvr_dev)->dev,
107 			       mips_data->pt_dma_addr[page_nr], PAGE_SIZE, DMA_TO_DEVICE);
108 
109 		__free_page(mips_data->pt_pages[page_nr]);
110 	}
111 
112 	fw_dev->processor_data.mips_data = NULL;
113 }
114 
115 static u32
116 get_mips_pte_flags(bool read, bool write, u32 cache_policy)
117 {
118 	u32 flags = 0;
119 
120 	if (read && write) /* Read/write. */
121 		flags |= ROGUE_MIPSFW_ENTRYLO_DIRTY_EN;
122 	else if (write)    /* Write only. */
123 		flags |= ROGUE_MIPSFW_ENTRYLO_READ_INHIBIT_EN;
124 	else
125 		WARN_ON(!read);
126 
127 	flags |= cache_policy << ROGUE_MIPSFW_ENTRYLO_CACHE_POLICY_SHIFT;
128 
129 	flags |= ROGUE_MIPSFW_ENTRYLO_VALID_EN | ROGUE_MIPSFW_ENTRYLO_GLOBAL_EN;
130 
131 	return flags;
132 }
133 
134 /**
135  * pvr_vm_mips_map() - Map a FW object into MIPS address space
136  * @pvr_dev: Target PowerVR device.
137  * @fw_obj: FW object to map.
138  *
139  * Returns:
140  *  * 0 on success,
141  *  * -%EINVAL if object does not reside within FW address space, or
142  *  * Any error returned by pvr_fw_object_get_dma_addr().
143  */
144 int
145 pvr_vm_mips_map(struct pvr_device *pvr_dev, struct pvr_fw_object *fw_obj)
146 {
147 	struct pvr_fw_device *fw_dev = &pvr_dev->fw_dev;
148 	struct pvr_fw_mips_data *mips_data = fw_dev->processor_data.mips_data;
149 	struct pvr_gem_object *pvr_obj = fw_obj->gem;
150 	const u64 start = fw_obj->fw_mm_node.start;
151 	const u64 size = fw_obj->fw_mm_node.size;
152 	u64 end;
153 	u32 cache_policy;
154 	u32 pte_flags;
155 	s32 start_pfn;
156 	s32 end_pfn;
157 	s32 pfn;
158 	int err;
159 
160 	if (check_add_overflow(start, size - 1, &end))
161 		return -EINVAL;
162 
163 	if (start < ROGUE_FW_HEAP_BASE ||
164 	    start >= ROGUE_FW_HEAP_BASE + fw_dev->fw_heap_info.raw_size ||
165 	    end < ROGUE_FW_HEAP_BASE ||
166 	    end >= ROGUE_FW_HEAP_BASE + fw_dev->fw_heap_info.raw_size ||
167 	    (start & ROGUE_MIPSFW_PAGE_MASK_4K) ||
168 	    ((end + 1) & ROGUE_MIPSFW_PAGE_MASK_4K))
169 		return -EINVAL;
170 
171 	start_pfn = (start & fw_dev->fw_heap_info.offset_mask) >> ROGUE_MIPSFW_LOG2_PAGE_SIZE_4K;
172 	end_pfn = (end & fw_dev->fw_heap_info.offset_mask) >> ROGUE_MIPSFW_LOG2_PAGE_SIZE_4K;
173 
174 	if (pvr_obj->flags & PVR_BO_FW_FLAGS_DEVICE_UNCACHED)
175 		cache_policy = ROGUE_MIPSFW_UNCACHED_CACHE_POLICY;
176 	else
177 		cache_policy = mips_data->cache_policy;
178 
179 	pte_flags = get_mips_pte_flags(true, true, cache_policy);
180 
181 	for (pfn = start_pfn; pfn <= end_pfn; pfn++) {
182 		dma_addr_t dma_addr;
183 		u32 pte;
184 
185 		err = pvr_fw_object_get_dma_addr(fw_obj,
186 						 (pfn - start_pfn) <<
187 						 ROGUE_MIPSFW_LOG2_PAGE_SIZE_4K,
188 						 &dma_addr);
189 		if (err)
190 			goto err_unmap_pages;
191 
192 		pte = ((dma_addr >> ROGUE_MIPSFW_LOG2_PAGE_SIZE_4K)
193 		       << ROGUE_MIPSFW_ENTRYLO_PFN_SHIFT) & mips_data->pfn_mask;
194 		pte |= pte_flags;
195 
196 		WRITE_ONCE(mips_data->pt[pfn], pte);
197 	}
198 
199 	pvr_mmu_flush_request_all(pvr_dev);
200 
201 	return 0;
202 
203 err_unmap_pages:
204 	while (--pfn >= start_pfn)
205 		WRITE_ONCE(mips_data->pt[pfn], 0);
206 
207 	pvr_mmu_flush_request_all(pvr_dev);
208 	WARN_ON(pvr_mmu_flush_exec(pvr_dev, true));
209 
210 	return err;
211 }
212 
213 /**
214  * pvr_vm_mips_unmap() - Unmap a FW object into MIPS address space
215  * @pvr_dev: Target PowerVR device.
216  * @fw_obj: FW object to unmap.
217  */
218 void
219 pvr_vm_mips_unmap(struct pvr_device *pvr_dev, struct pvr_fw_object *fw_obj)
220 {
221 	struct pvr_fw_device *fw_dev = &pvr_dev->fw_dev;
222 	struct pvr_fw_mips_data *mips_data = fw_dev->processor_data.mips_data;
223 	const u64 start = fw_obj->fw_mm_node.start;
224 	const u64 size = fw_obj->fw_mm_node.size;
225 	const u64 end = start + size;
226 
227 	const u32 start_pfn = (start & fw_dev->fw_heap_info.offset_mask) >>
228 			      ROGUE_MIPSFW_LOG2_PAGE_SIZE_4K;
229 	const u32 end_pfn = (end & fw_dev->fw_heap_info.offset_mask) >>
230 			    ROGUE_MIPSFW_LOG2_PAGE_SIZE_4K;
231 
232 	for (u32 pfn = start_pfn; pfn < end_pfn; pfn++)
233 		WRITE_ONCE(mips_data->pt[pfn], 0);
234 
235 	pvr_mmu_flush_request_all(pvr_dev);
236 	WARN_ON(pvr_mmu_flush_exec(pvr_dev, true));
237 }
238