[Pdbg] [PATCH 2/3] libpdg: Add option to write to / read from cache inhibited memory

[Alistair Popple]

Thanks Rashmica, this looks pretty good. One minor note below but otherwise I
think this is fine as is.

> diff --git a/libpdbg/libpdbg.h b/libpdbg/libpdbg.h
> index f2b5de7..8601361 100644
> --- a/libpdbg/libpdbg.h
> +++ b/libpdbg/libpdbg.h
> @@ -120,8 +120,8 @@ int htm_status(struct pdbg_target *target);
>  int htm_reset(struct pdbg_target *target, uint64_t *base, uint64_t *size);
>  int htm_dump(struct pdbg_target *target, uint64_t size, const char *filename);
>  
> -int adu_getmem(struct pdbg_target *target, uint64_t addr, uint8_t *ouput, uint64_t size);
> -int adu_putmem(struct pdbg_target *target, uint64_t addr, uint8_t *input, uint64_t size);
> +int adu_getmem(struct pdbg_target *target, uint64_t addr, uint8_t *ouput, uint64_t size, int ci);
> +int adu_putmem(struct pdbg_target *target, uint64_t addr, uint8_t *input, uint64_t size, int ci);

Technically this is a change to the existing API/ABI for the library which will
break existing programs/binaries. For a bigger project we'd probably want to
avoid this, but at the moment the only real user of libpdbg is pdbg itself so I
don't think we have to worry too much.

- Alistair

>  int opb_read(struct pdbg_target *target, uint32_t addr, uint32_t *data);
>  int opb_write(struct pdbg_target *target, uint32_t addr, uint32_t data);
> diff --git a/libpdbg/operations.h b/libpdbg/operations.h
> index d6c947f..7ee4cb2 100644
> --- a/libpdbg/operations.h
> +++ b/libpdbg/operations.h
> @@ -32,8 +32,8 @@
>  #define FSI2PIB_BASE	0x1000
>  
>  /* Alter display unit functions */
> -int adu_getmem(struct pdbg_target *target, uint64_t addr, uint8_t *output, uint64_t size);
> -int adu_putmem(struct pdbg_target *target, uint64_t start_addr, uint8_t *input, uint64_t size);
> +int adu_getmem(struct pdbg_target *target, uint64_t addr, uint8_t *output, uint64_t size, int ci);
> +int adu_putmem(struct pdbg_target *target, uint64_t start_addr, uint8_t *input, uint64_t size, int ci);
>  
>  /* Functions to ram instructions */
>  #define THREAD_STATUS_DISABLED  PPC_BIT(0)
> diff --git a/libpdbg/target.h b/libpdbg/target.h
> index eba26cb..d60c586 100644
> --- a/libpdbg/target.h
> +++ b/libpdbg/target.h
> @@ -103,8 +103,8 @@ struct htm {
>  
>  struct adu {
>  	struct pdbg_target target;
> -	int (*getmem)(struct adu *, uint64_t, uint64_t *);
> -	int (*putmem)(struct adu *, uint64_t, uint64_t, int);
> +	int (*getmem)(struct adu *, uint64_t, uint64_t *, int);
> +	int (*putmem)(struct adu *, uint64_t, uint64_t, int, int);
>  };
>  #define target_to_adu(x) container_of(x, struct adu, target)
>  
> diff --git a/src/mem.c b/src/mem.c
> index 815c1c7..be45434 100644
> --- a/src/mem.c
> +++ b/src/mem.c
> @@ -26,7 +26,7 @@
>  #include "main.h"
>  
>  #define PUTMEM_BUF_SIZE 1024
> -static int getmem(uint64_t addr, uint64_t size)
> +static int getmem(uint64_t addr, uint64_t size, int ci)
>  {
>  	struct pdbg_target *target;
>  	uint8_t *buf;
> @@ -37,7 +37,7 @@ static int getmem(uint64_t addr, uint64_t size)
>  		if (pdbg_target_probe(target) != PDBG_TARGET_ENABLED)
>  			continue;
>  
> -		if (!adu_getmem(target, addr, buf, size)) {
> +		if (!adu_getmem(target, addr, buf, size, ci)) {
>  			if (write(STDOUT_FILENO, buf, size) < 0)
>  				PR_ERROR("Unable to write stdout.\n");
>  			else
> @@ -51,7 +51,7 @@ static int getmem(uint64_t addr, uint64_t size)
>  	return rc;
>  
>  }
> -static int putmem(uint64_t addr)
> +static int putmem(uint64_t addr, int ci)
>  {
>  	uint8_t *buf;
>  	int read_size, rc = 0;
> @@ -67,7 +67,7 @@ static int putmem(uint64_t addr)
>  	assert(buf);
>  	do {
>  		read_size = read(STDIN_FILENO, buf, PUTMEM_BUF_SIZE);
> -		if (adu_putmem(adu_target, addr, buf, read_size)) {
> +		if (adu_putmem(adu_target, addr, buf, read_size, ci)) {
>  			rc = 0;
>  			printf("Unable to write memory.\n");
>  			break;
> @@ -84,6 +84,7 @@ int handle_mem(int optind, int argc, char *argv[])
>  {
>  	uint64_t addr;
>  	char *endptr;
> +	int ci = 0;
>  
>  	if (optind + 1 >= argc) {
>  		printf("%s: command '%s' requires an address\n", argv[0], argv[optind]);
> @@ -91,31 +92,37 @@ int handle_mem(int optind, int argc, char *argv[])
>  	}
>  
>  	errno = 0;
> -	addr = strtoull(argv[optind + 1], &endptr, 0);
> +
> +	if (strcmp(argv[optind +1], "-ci") == 0) {
> +		/* Set cache-inhibited flag */
> +		ci = 1;
> +	}
> +
> +	addr = strtoull(argv[optind + 1 + ci], &endptr, 0);
>  	if (errno || *endptr != '\0') {
>  		printf("%s: command '%s' couldn't parse address '%s'\n",
> -				argv[0], argv[optind], argv[optind + 1]);
> +				argv[0], argv[optind], argv[optind + 1 + ci]);
>  		return -1;
>  	}
>  
>  	if (strcmp(argv[optind], "getmem") == 0) {
>  		uint64_t size;
>  
> -		if (optind + 2 >= argc) {
> +		if (optind + 2 + ci >= argc) {
>  			printf("%s: command '%s' requires data\n", argv[0], argv[optind]);
>  			return -1;
>  		}
>  
>  		errno = 0;
> -		size = strtoull(argv[optind + 2], &endptr, 0);
> +		size = strtoull(argv[optind + 2 + ci], &endptr, 0);
>  		if (errno || *endptr != '\0') {
>  			printf("%s: command '%s' couldn't parse data '%s'\n",
> -				argv[0], argv[optind], argv[optind + 1]);
> +				argv[0], argv[optind], argv[optind + 1 + ci]);
>  			return -1;
>  		}
>  
> -		return getmem(addr, size);
> +		return getmem(addr, size, ci);
>  	}
>  
> -	return putmem(addr);
> +	return putmem(addr, ci);
>  }
>