Re: [coreboot] [PATCH] flashrom: Abstraction for flash mapping/unmapping

[Carl-Daniel Hailfinger]

On 09.05.2009 14:06, Carl-Daniel Hailfinger wrote:
> Flash mapping/unmapping was performed without an abstraction layer, so
> even the dummy flasher caused memory mappings to be set up.
> Add map/unmap functions to the external flasher abstraction.
>
> Fix a possible scribble-over-low-memory corner case which fortunately
> never triggered so far.
>
> With this patch, --programmer dummy works fine as non-root.
>
> Signed-off-by: Carl-Daniel Hailfinger

If this gets an Ack, I'll send a dummy SPI flasher driver next.

Regards,
Carl-Daniel
> Index: flashrom-external_map_region/flash.h
>
> --- flashrom-external_map_region/flash.h	(Revision 489)
> +++ flashrom-external_map_region/flash.h	(Arbeitskopie)
> @@ -87,6 +87,9 @@
>    int (*init) (void);
>    int (*shutdown) (void);
> void * (*map_flash_region) (const char *descr, unsigned long phys_addr, size_t len);
> void (*unmap_flash_region) (void *virt_addr, size_t len);
> void (*chip_writeb) (uint8_t val, volatile void *addr);
>  void (*chip_writew) (uint16_t val, volatile void *addr);
>  void (*chip_writel) (uint32_t val, volatile void *addr);
>
> @@ -107,6 +110,16 @@
>    return programmer_table[programmer].shutdown();
>  }
>
> +static inline void *programmer_map_flash_region(const char *descr, unsigned long phys_addr, size_t len)
> +{
> return programmer_table[programmer].map_flash_region(descr, phys_addr, len);
>
> +}
>
> +static inline void programmer_unmap_flash_region(void *virt_addr, size_t len)
> +{
> programmer_table[programmer].unmap_flash_region(virt_addr, len);
>
> +}
>
> static inline void chip_writeb(uint8_t val, volatile void *addr)
>  {
>    programmer_table[programmer].chip_writeb(val, addr);
> @@ -579,6 +592,8 @@
>  /* dummyflasher.c */
>  int dummy_init(void);
>  int dummy_shutdown(void);
> +void *dummy_map(const char *descr, unsigned long phys_addr, size_t len);
> +void dummy_unmap(void *virt_addr, size_t len);
>  void dummy_chip_writeb(uint8_t val, volatile void *addr);
>  void dummy_chip_writew(uint16_t val, volatile void *addr);
>  void dummy_chip_writel(uint32_t val, volatile void *addr);
> Index: flashrom-external_map_region/physmap.c
> ===================================================================
> --- flashrom-external_map_region/physmap.c	(Revision 489)
> +++ flashrom-external_map_region/physmap.c	(Arbeitskopie)
> @@ -69,12 +69,34 @@
>
> void physunmap(void *virt_addr, size_t len)
>  {
> if (len == 0) {
> fprintf(stderr, "Not unmapping zero size at %p\n",
> 	virt_addr);
> return;
> }
> munmap(virt_addr, len);
>
> }
>  #endif
>
> void *physmap(const char *descr, unsigned long phys_addr, size_t len)
>  {
>
> if (len == 0) {
> fprintf(stderr, "Not mapping %s, zero size at 0x%08lx\n",
> 	descr, phys_addr);
> return NULL;
>
> }
>
> if ((getpagesize() - 1) & len) {
> fprintf(stderr, "Mapping %s at 0x%08lx, unaligned size 0x%lx\n",
> 	descr, phys_addr, (unsigned long)len);
>
> }
>
> if ((getpagesize() - 1) & phys_addr) {
> fprintf(stderr, "Mapping %s, 0x%lx bytes at unaligned 0x%08lx\n",
> 	descr, (unsigned long)len, phys_addr);
>
> }
>
> void *virt_addr = sys_physmap(phys_addr, len);
>
> if (NULL == virt_addr) {
> Index: flashrom-external_map_region/dummyflasher.c
>
> --- flashrom-external_map_region/dummyflasher.c	(Revision 489)
> +++ flashrom-external_map_region/dummyflasher.c	(Arbeitskopie)
> @@ -40,6 +40,19 @@
>    return 0;
>  }
>
> +void *dummy_map(const char *descr, unsigned long phys_addr, size_t len)
> +{
> printf("%s: Mapping %s, 0x%lx bytes at 0x%08lx\n",
> __func__, descr, (unsigned long)len, phys_addr);
> return (void *)phys_addr;
>
> +}
>
> +void dummy_unmap(void *virt_addr, size_t len)
> +{
> printf("%s: Unmapping 0x%lx bytes at %p\n",
> __func__, (unsigned long)len, virt_addr);
>
> +}
>
> void dummy_chip_writeb(uint8_t val, volatile void *addr)
>  {
>    printf("%s: addr=%p, val=0x%02x\n", __func__, addr, val);
> Index: flashrom-external_map_region/flashrom.c
> ===================================================================
> --- flashrom-external_map_region/flashrom.c	(Revision 489)
> +++ flashrom-external_map_region/flashrom.c	(Arbeitskopie)
> @@ -40,6 +40,8 @@
>    {
>    	.init		= internal_init,
>    	.shutdown	= internal_shutdown,
> .map_flash_region = physmap,
> .unmap_flash_region = physunmap,
> .chip_readb	= internal_chip_readb,
> .chip_readw	= internal_chip_readw,
> .chip_readl	= internal_chip_readl,
>
> @@ -51,6 +53,8 @@
>    {
>    	.init		= dummy_init,
>    	.shutdown	= dummy_shutdown,
> .map_flash_region = dummy_map,
> .unmap_flash_region = dummy_unmap,
> .chip_readb	= dummy_chip_readb,
> .chip_readw	= dummy_chip_readw,
> .chip_readl	= dummy_chip_readl,
>
> @@ -65,7 +69,7 @@
>  void map_flash_registers(struct flashchip *flash)
>  {
>    size_t size = flash->total_size * 1024;
> flash->virtual_registers = physmap("flash chip registers", (0xFFFFFFFF - 0x400000 - size + 1), size);
> flash->virtual_registers = programmer_map_flash_region("flash chip registers", (0xFFFFFFFF - 0x400000 - size + 1), size);
>
> }
>
> int read_memmapped(struct flashchip *flash, uint8_t *buf)
> @@ -97,23 +101,8 @@
> size = flash->total_size * 1024;
>
> /* If getpagesize() > size -> 
>  * "Can't mmap memory using /dev/mem: Invalid argument"
>  * This should never happen as we don't support any flash chips
>  * smaller than 4k or 8k (yet).
>  */
> if (getpagesize() > size) {
> 	/*
> 	 * if a flash size of 0 is mapped, we map a single page
> 	 * so we can probe in that area whether we know the
> 	 * vendor at least.
> 	 */
> 	size = getpagesize();
> }
> base = flashbase ? flashbase : (0xffffffff - size + 1);
> flash->virtual_memory = physmap("flash chip", base, size);
> flash->virtual_memory = programmer_map_flash_region("flash chip", base, size);
>
> if (force)
> 	break;
>
> @@ -126,7 +115,8 @@
>    		break;
>
> notfound:
> physunmap((void *)flash->virtual_memory, size);
> /* The intermediate cast to unsigned long works around a gcc warning bug. */
> programmer_unmap_flash_region((void *)(unsigned long)flash->virtual_memory, size);
>
> }
>
> if (!flash || !flash->name)