Ticket #109: flashrom_sc520.diff

Makefile

@@ -11 +11 @@
 INSTALL = /usr/bin/install
 PREFIX  = /usr/local
 #CFLAGS  = -O2 -g -Wall -Werror
-CFLAGS  = -Os -Wall -Werror # -DTS5300
+CFLAGS  = -Os -Wall -Werror
 OS_ARCH = $(shell uname)
 ifeq ($(OS_ARCH), SunOS)
 LDFLAGS = -lpci -lz

flashrom.c

@@ -119 +119 @@
 
                 size = flash->total_size * 1024;
 
-#ifdef TS5300
-                // FIXME: Wrong place for this decision
-                // FIXME: This should be autodetected. It is trivial.
-                flash_baseaddr = 0x9400000;
-#else
+
+                // FIXME Calculating the flash base address now. This is the
+                // wrong place to do this.
+
+                /* Usually on the x86 architectures (and on other PC-like
+                 * platforms like some Alphas or Itanium) the system flash
+                 * is mapped right below 4G.
+                 * On the AMD Elan SC520 only a small piece of the system flash
+                 * is mapped there, but the complete flash is mapped somewhere
+                 * below 1G. The position can be determined by the BOOTCS PAR
+                 * register
+                 */
+
+                /* Assume default PC architecture */
                 flash_baseaddr = (0xffffffff - size + 1);
-#endif
 
+                if (pci_dev_find(0x1022, 0x3000) != NULL) { /* Elan SC520 */
+                        int i, bootcs_found = 0;
+                        uint32_t parx = 0;
+                        void *mmcr;
+
+                        /* 1. Map MMCR */
+                        mmcr = mmap(0, getpagesize(), PROT_WRITE | PROT_READ,
+                                        MAP_SHARED, fd_mem, (off_t)0xFFFEF000);
+
+                        if (mmcr == MAP_FAILED) {
+                                perror("Can't mmap Elan SC520 specific registers using " MEM_DEV);
+                                exit(1);
+                        }
+
+                        /* 2. Scan PAR0 (0x88) - PAR15 (0xc4) for 
+                         *    BOOTCS region (PARx[31:29] = 100b)
+                         */
+                        for (i = 0x88; i <= 0xc4; i += 4) {
+                                parx = *(volatile uint32_t *)(mmcr + i);
+                                if ((parx >> 29) == 4) {
+                                        bootcs_found = 1;
+                                        break; /* BOOTCS found */
+                                }
+                        }
+
+                        /* 3. PARx[25] = 1b --> flash_baseaddr[29:16] = PARx[13:0]
+                         *    PARx[25] = 0b --> flash_baseaddr[29:12] = PARx[17:0]
+                         */
+                        if (bootcs_found) {
+                                if (parx & (1 << 25)) {
+                                        parx &= (1 << 14) - 1; /* Mask [13:0] */
+                                        flash_baseaddr = parx << 16;
+                                } else {
+                                        parx &= (1 << 18) - 1; /* Mask [17:0] */
+                                        flash_baseaddr = parx << 12;
+                                }
+                        } else {
+                                printf("AMD Elan SC520 detected, but no BOOTCS. Assuming flash at 4G\n");
+                        }
+
+                        /* 4. Clean up */
+                        munmap (mmcr, getpagesize());
+                }
+
                 /* If getpagesize() > size -> 
                  * "Can't mmap memory using /dev/mem: Invalid argument"
                  * This should never happen as we don't support any flash chips