xref: /linux/drivers/scsi/isci/probe_roms.c (revision 52ae18ac80fbdd268720b0daa27ac797a801500c)
1 /*
2  * This file is provided under a dual BSD/GPLv2 license.  When using or
3  * redistributing this file, you may do so under either license.
4  *
5  * GPL LICENSE SUMMARY
6  *
7  * Copyright(c) 2008 - 2011 Intel Corporation. All rights reserved.
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of version 2 of the GNU General Public License as
11  * published by the Free Software Foundation.
12  *
13  * This program is distributed in the hope that it will be useful, but
14  * WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
16  * General Public License for more details.
17  *
18  * You should have received a copy of the GNU General Public License
19  * along with this program; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
21  * The full GNU General Public License is included in this distribution
22  * in the file called LICENSE.GPL.
23  */
24 
25 /* probe_roms - scan for oem parameters */
26 
27 #include <linux/kernel.h>
28 #include <linux/firmware.h>
29 #include <linux/uaccess.h>
30 #include <linux/efi.h>
31 #include <asm/probe_roms.h>
32 
33 #include "isci.h"
34 #include "task.h"
35 #include "sci_controller_constants.h"
36 #include "scic_remote_device.h"
37 #include "sci_environment.h"
38 #include "probe_roms.h"
39 
40 struct efi_variable {
41 	efi_char16_t  VariableName[1024/sizeof(efi_char16_t)];
42 	efi_guid_t    VendorGuid;
43 	unsigned long DataSize;
44 	__u8          Data[1024];
45 	efi_status_t  Status;
46 	__u32         Attributes;
47 } __attribute__((packed));
48 
49 struct isci_orom *isci_request_oprom(struct pci_dev *pdev)
50 {
51 	void __iomem *oprom = pci_map_biosrom(pdev);
52 	struct isci_orom *rom = NULL;
53 	size_t len, i;
54 	int j;
55 	char oem_sig[4];
56 	struct isci_oem_hdr oem_hdr;
57 	u8 *tmp, sum;
58 
59 	if (!oprom)
60 		return NULL;
61 
62 	len = pci_biosrom_size(pdev);
63 	rom = devm_kzalloc(&pdev->dev, sizeof(*rom), GFP_KERNEL);
64 	if (!rom) {
65 		dev_warn(&pdev->dev,
66 			 "Unable to allocate memory for orom\n");
67 		return NULL;
68 	}
69 
70 	for (i = 0; i < len && rom; i += ISCI_OEM_SIG_SIZE) {
71 		memcpy_fromio(oem_sig, oprom + i, ISCI_OEM_SIG_SIZE);
72 
73 		/* we think we found the OEM table */
74 		if (memcmp(oem_sig, ISCI_OEM_SIG, ISCI_OEM_SIG_SIZE) == 0) {
75 			size_t copy_len;
76 
77 			memcpy_fromio(&oem_hdr, oprom + i, sizeof(oem_hdr));
78 
79 			copy_len = min(oem_hdr.len - sizeof(oem_hdr),
80 				       sizeof(*rom));
81 
82 			memcpy_fromio(rom,
83 				      oprom + i + sizeof(oem_hdr),
84 				      copy_len);
85 
86 			/* calculate checksum */
87 			tmp = (u8 *)&oem_hdr;
88 			for (j = 0, sum = 0; j < sizeof(oem_hdr); j++, tmp++)
89 				sum += *tmp;
90 
91 			tmp = (u8 *)rom;
92 			for (j = 0; j < sizeof(*rom); j++, tmp++)
93 				sum += *tmp;
94 
95 			if (sum != 0) {
96 				dev_warn(&pdev->dev,
97 					 "OEM table checksum failed\n");
98 				continue;
99 			}
100 
101 			/* keep going if that's not the oem param table */
102 			if (memcmp(rom->hdr.signature,
103 				   ISCI_ROM_SIG,
104 				   ISCI_ROM_SIG_SIZE) != 0)
105 				continue;
106 
107 			dev_info(&pdev->dev,
108 				 "OEM parameter table found in OROM\n");
109 			break;
110 		}
111 	}
112 
113 	if (i >= len) {
114 		dev_err(&pdev->dev, "oprom parse error\n");
115 		devm_kfree(&pdev->dev, rom);
116 		rom = NULL;
117 	}
118 	pci_unmap_biosrom(oprom);
119 
120 	return rom;
121 }
122 
123 /**
124  * isci_parse_oem_parameters() - This method will take OEM parameters
125  *    from the module init parameters and copy them to oem_params. This will
126  *    only copy values that are not set to the module parameter default values
127  * @oem_parameters: This parameter specifies the controller default OEM
128  *    parameters. It is expected that this has been initialized to the default
129  *    parameters for the controller
130  *
131  *
132  */
133 enum sci_status isci_parse_oem_parameters(union scic_oem_parameters *oem_params,
134 					  struct isci_orom *orom, int scu_index)
135 {
136 	/* check for valid inputs */
137 	if (scu_index < 0 || scu_index > SCI_MAX_CONTROLLERS ||
138 	    scu_index > orom->hdr.num_elements || !oem_params)
139 		return -EINVAL;
140 
141 	oem_params->sds1 = orom->ctrl[scu_index];
142 	return 0;
143 }
144 
145 struct isci_orom *isci_request_firmware(struct pci_dev *pdev, const struct firmware *fw)
146 {
147 	struct isci_orom *orom = NULL, *data;
148 
149 	if (request_firmware(&fw, ISCI_FW_NAME, &pdev->dev) != 0)
150 		return NULL;
151 
152 	if (fw->size < sizeof(*orom))
153 		goto out;
154 
155 	data = (struct isci_orom *)fw->data;
156 
157 	if (strncmp(ISCI_ROM_SIG, data->hdr.signature,
158 		    strlen(ISCI_ROM_SIG)) != 0)
159 		goto out;
160 
161 	orom = devm_kzalloc(&pdev->dev, fw->size, GFP_KERNEL);
162 	if (!orom)
163 		goto out;
164 
165 	memcpy(orom, fw->data, fw->size);
166 
167  out:
168 	release_firmware(fw);
169 
170 	return orom;
171 }
172 
173 static struct efi *get_efi(void)
174 {
175 	#ifdef CONFIG_EFI
176 	return &efi;
177 	#else
178 	return NULL;
179 	#endif
180 }
181 
182 struct isci_orom *isci_get_efi_var(struct pci_dev *pdev)
183 {
184 	struct efi_variable *evar;
185 	efi_status_t status;
186 	struct isci_orom *rom = NULL;
187 	struct isci_oem_hdr *oem_hdr;
188 	u8 *tmp, sum;
189 	int j;
190 	size_t copy_len;
191 
192 	evar = devm_kzalloc(&pdev->dev,
193 			    sizeof(struct efi_variable),
194 			    GFP_KERNEL);
195 	if (!evar) {
196 		dev_warn(&pdev->dev,
197 			 "Unable to allocate memory for EFI var\n");
198 		return NULL;
199 	}
200 
201 	rom = devm_kzalloc(&pdev->dev, sizeof(*rom), GFP_KERNEL);
202 	if (!rom) {
203 		dev_warn(&pdev->dev,
204 			 "Unable to allocate memory for orom\n");
205 		return NULL;
206 	}
207 
208 	for (j = 0; j < strlen(ISCI_EFI_VAR_NAME) + 1; j++)
209 		evar->VariableName[j] = ISCI_EFI_VAR_NAME[j];
210 
211 	evar->DataSize = 1024;
212 	evar->VendorGuid = ISCI_EFI_VENDOR_GUID;
213 	evar->Attributes = ISCI_EFI_ATTRIBUTES;
214 
215 	if (get_efi())
216 		status = get_efi()->get_variable(evar->VariableName,
217 						 &evar->VendorGuid,
218 						 &evar->Attributes,
219 						 &evar->DataSize,
220 						 evar->Data);
221 	else
222 		status = EFI_NOT_FOUND;
223 
224 	if (status != EFI_SUCCESS) {
225 		dev_warn(&pdev->dev,
226 			 "Unable to obtain EFI variable for OEM parms\n");
227 		return NULL;
228 	}
229 
230 	oem_hdr = (struct isci_oem_hdr *)evar->Data;
231 
232 	if (memcmp(oem_hdr->sig, ISCI_OEM_SIG, ISCI_OEM_SIG_SIZE) != 0) {
233 		dev_warn(&pdev->dev,
234 			 "Invalid OEM header signature\n");
235 		return NULL;
236 	}
237 
238 	/* calculate checksum */
239 	tmp = (u8 *)oem_hdr;
240 	for (j = 0, sum = 0; j < sizeof(oem_hdr); j++, tmp++)
241 		sum += *tmp;
242 
243 	tmp = (u8 *)rom;
244 	for (j = 0; j < sizeof(*rom); j++, tmp++)
245 		sum += *tmp;
246 
247 	if (sum != 0) {
248 		dev_warn(&pdev->dev,
249 			 "OEM table checksum failed\n");
250 		return NULL;
251 	}
252 
253 	copy_len = min_t(u16, evar->DataSize,
254 			 min_t(u16, oem_hdr->len - sizeof(*oem_hdr), sizeof(*rom)));
255 
256 	memcpy(rom, (char *)evar->Data + sizeof(*oem_hdr), copy_len);
257 
258 	if (memcmp(rom->hdr.signature,
259 		   ISCI_ROM_SIG,
260 		   ISCI_ROM_SIG_SIZE) != 0) {
261 		dev_warn(&pdev->dev,
262 			 "Invalid OEM table signature\n");
263 		return NULL;
264 	}
265 
266 	return rom;
267 }
268