[PATCH V3 2/8] powerpc/memory: Parse new memory property to register blocks.

[PATCH V3 2/8] powerpc/memory: Parse new memory property to register blocks.

[Michael Bringmann]

powerpc/memory: Add parallel routines to parse the new property
"ibm,dynamic-memory-v2" property when it is present, and then to
register the relevant memory blocks with the operating system.
This property format is intended to provide a more compact
representation of memory when communicating with the front end
processor, especially when describing vast amounts of RAM.

Signed-off-by: Michael Bringmann <mwb@linux.vnet.ibm.com>
---
diff --git a/arch/powerpc/include/asm/prom.h b/arch/powerpc/include/asm/prom.h
index 7f436ba..b9a1534 100644
--- a/arch/powerpc/include/asm/prom.h
+++ b/arch/powerpc/include/asm/prom.h
@@ -69,6 +69,8 @@ struct boot_param_header {
  * OF address retreival & translation
  */
 
+extern int n_mem_addr_cells;
+
 /* Parse the ibm,dma-window property of an OF node into the busno, phys and
  * size parameters.
  */
@@ -81,8 +83,9 @@ extern void of_instantiate_rtc(void);
 extern int of_get_ibm_chip_id(struct device_node *np);
 
 /* The of_drconf_cell struct defines the layout of the LMB array
- * specified in the device tree property
- * ibm,dynamic-reconfiguration-memory/ibm,dynamic-memory
+ * specified in the device tree properties,
+ *     ibm,dynamic-reconfiguration-memory/ibm,dynamic-memory
+ *     ibm,dynamic-reconfiguration-memory/ibm,dynamic-memory-v2
  */
 struct of_drconf_cell {
 	u64	base_addr;
@@ -92,9 +95,32 @@ struct of_drconf_cell {
 	u32	flags;
 };
 
-#define DRCONF_MEM_ASSIGNED	0x00000008
-#define DRCONF_MEM_AI_INVALID	0x00000040
-#define DRCONF_MEM_RESERVED	0x00000080
+#define DRCONF_MEM_ASSIGNED		0x00000008
+#define DRCONF_MEM_AI_INVALID		0x00000040
+#define DRCONF_MEM_RESERVED		0x00000080
+
+struct of_drconf_cell_v2 {
+	u32	num_seq_lmbs;
+	u64	base_addr;
+	u32	drc_index;
+	u32	aa_index;
+	u32	flags;
+} __attribute__((packed));
+
+
+static inline int dyn_mem_v2_len(int entries)
+{
+	int drconf_v2_cells = (n_mem_addr_cells + 4);
+	int drconf_v2_cells_len = (drconf_v2_cells * sizeof(unsigned int));
+	return (((entries) * drconf_v2_cells_len) +
+                (1 * sizeof(unsigned int)));
+}
+
+extern void read_drconf_cell_v2(struct of_drconf_cell_v2 *drmem,
+				const __be32 **cellp);
+extern void read_one_drc_info(int **info, char **drc_type, char **drc_name,
+			unsigned long int *fdi_p, unsigned long int *nsl_p,
+			unsigned long int *si_p, unsigned long int *ldi_p);
 
 /*
  * There are two methods for telling firmware what our capabilities are.
diff --git a/arch/powerpc/mm/numa.c b/arch/powerpc/mm/numa.c
index 669a15e..ad294ce 100644
--- a/arch/powerpc/mm/numa.c
+++ b/arch/powerpc/mm/numa.c
@@ -57,8 +57,10 @@
 EXPORT_SYMBOL(node_data);
 
 static int min_common_depth;
-static int n_mem_addr_cells, n_mem_size_cells;
+int n_mem_addr_cells;
+static int n_mem_size_cells;
 static int form1_affinity;
+EXPORT_SYMBOL(n_mem_addr_cells);
 
 #define MAX_DISTANCE_REF_POINTS 4
 static int distance_ref_points_depth;
@@ -405,6 +405,24 @@ static void read_drconf_cell(struct of_drconf_cell *drmem, const __be32 **cellp)
 
 	*cellp = cp + 4;
 }
+ 
+ /*
+ * Retrieve and validate the ibm,dynamic-memory property of the device tree.
+ * Read the next memory block set entry from the ibm,dynamic-memory-v2 property
+ * and return the information in the provided of_drconf_cell_v2 structure.
+ */
+void read_drconf_cell_v2(struct of_drconf_cell_v2 *drmem, const __be32 **cellp)
+{
+	const __be32 *cp = (const __be32 *)*cellp;
+	drmem->num_seq_lmbs = be32_to_cpu(*cp++);
+	drmem->base_addr = read_n_cells(n_mem_addr_cells, &cp);
+	drmem->drc_index = be32_to_cpu(*cp++);
+	drmem->aa_index = be32_to_cpu(*cp++);
+	drmem->flags = be32_to_cpu(*cp++);
+
+	*cellp = cp;
+}
+EXPORT_SYMBOL(read_drconf_cell_v2);
 
 /*
  * Retrieve and validate the ibm,dynamic-memory property of the device tree.
diff --git a/arch/powerpc/kernel/prom.c b/arch/powerpc/kernel/prom.c
index 946e34f..b6f8ae5 100644
--- a/arch/powerpc/kernel/prom.c
+++ b/arch/powerpc/kernel/prom.c
@@ -441,12 +442,12 @@ static int __init early_init_dt_scan_chosen_ppc(unsigned long node,
 
 #ifdef CONFIG_PPC_PSERIES
 /*
- * Interpret the ibm,dynamic-memory property in the
- * /ibm,dynamic-reconfiguration-memory node.
+ * Interpret the ibm,dynamic-memory property/ibm,dynamic-memory-v2
+ * in the /ibm,dynamic-reconfiguration-memory node.
  * This contains a list of memory blocks along with NUMA affinity
  * information.
  */
-static int __init early_init_dt_scan_drconf_memory(unsigned long node)
+static int __init early_init_dt_scan_drconf_memory_v1(unsigned long node)
 {
 	const __be32 *dm, *ls, *usm;
 	int l;
@@ -516,6 +517,73 @@ static int __init early_init_dt_scan_drconf_memory(unsigned long node)
 	memblock_dump_all();
 	return 0;
 }
+
+static int __init early_init_dt_scan_drconf_memory_v2(unsigned long node)
+{
+	const __be32 *dm, *ls;
+	int l;
+	unsigned long num_sets;
+	u64 size, base, memblock_size;
+
+	ls = of_get_flat_dt_prop(node, "ibm,lmb-size", &l);
+	if (ls == NULL || l < dt_root_size_cells * sizeof(__be32))
+		return 0;
+	memblock_size = dt_mem_next_cell(dt_root_size_cells, &ls);
+
+	dm = of_get_flat_dt_prop(node, "ibm,dynamic-memory-v2", &l);
+	if (dm == NULL || l < sizeof(__be32))
+		return 0;
+
+	num_sets = of_read_number(dm++, 1);
+	if (l < (num_sets * (dt_root_addr_cells + 4) + 1) * sizeof(__be32))
+		return 0;
+
+	if (n_mem_addr_cells == 0)
+		n_mem_addr_cells = dt_root_addr_cells;
+
+	for (; num_sets != 0; --num_sets) {
+		struct of_drconf_cell_v2 drmem;
+		unsigned long nsl;
+
+		read_drconf_cell_v2(&drmem, &dm);
+		base = drmem.base_addr;
+		nsl = drmem.num_seq_lmbs;
+		size = memblock_size;
+
+		/* SKip this block if the reserved bit is set in flags
+		 * or if the block is not assigned to this partition
+		 */
+		if ((drmem.flags & DRCONF_MEM_RESERVED) ||
+		    !(drmem.flags & DRCONF_MEM_ASSIGNED))
+			continue;
+
+		for (; nsl != 0; nsl--) {
+			size = memblock_size;
+
+			if (iommu_is_off) {
+				if (base >= 0x80000000ul)
+					continue;
+				if ((base + size) > 0x80000000ul)
+					size = 0x80000000ul - base;
+			}
+			memblock_add(base, size);
+
+			base += size;
+		}
+	}
+
+	memblock_dump_all();
+	return 0;
+}
+
+static int __init early_init_dt_scan_drconf_memory(unsigned long node)
+{
+	if (firmware_has_feature(FW_FEATURE_DYN_MEM_V2))
+		return early_init_dt_scan_drconf_memory_v2(node);
+	else
+		return early_init_dt_scan_drconf_memory_v1(node);
+}
+
 #else
 #define early_init_dt_scan_drconf_memory(node)	0
 #endif /* CONFIG_PPC_PSERIES */

Re: [PATCH V3 2/8] powerpc/memory: Parse new memory property to register blocks.

[Nathan Fontenot]

On 08/01/2016 08:24 PM, Michael Bringmann wrote:
> powerpc/memory: Add parallel routines to parse the new property
> "ibm,dynamic-memory-v2" property when it is present, and then to
> register the relevant memory blocks with the operating system.
> This property format is intended to provide a more compact
> representation of memory when communicating with the front end
> processor, especially when describing vast amounts of RAM.
> 
> Signed-off-by: Michael Bringmann <mwb@linux.vnet.ibm.com>
> ---

It's generally a good idea to include a short description of what
changed in the patch between patch versions. This helps reviewers
avoid digging through the patch and trying to find updates.

> diff --git a/arch/powerpc/include/asm/prom.h b/arch/powerpc/include/asm/prom.h
> index 7f436ba..b9a1534 100644
> --- a/arch/powerpc/include/asm/prom.h
> +++ b/arch/powerpc/include/asm/prom.h
> @@ -69,6 +69,8 @@ struct boot_param_header {
>   * OF address retreival & translation
>   */
>  
> +extern int n_mem_addr_cells;
> +
>  /* Parse the ibm,dma-window property of an OF node into the busno, phys and
>   * size parameters.
>   */
> @@ -81,8 +83,9 @@ extern void of_instantiate_rtc(void);
>  extern int of_get_ibm_chip_id(struct device_node *np);
>  
>  /* The of_drconf_cell struct defines the layout of the LMB array
> - * specified in the device tree property
> - * ibm,dynamic-reconfiguration-memory/ibm,dynamic-memory
> + * specified in the device tree properties,
> + *     ibm,dynamic-reconfiguration-memory/ibm,dynamic-memory
> + *     ibm,dynamic-reconfiguration-memory/ibm,dynamic-memory-v2
>   */
>  struct of_drconf_cell {
>  	u64	base_addr;
> @@ -92,9 +95,32 @@ struct of_drconf_cell {
>  	u32	flags;
>  };
>  
> -#define DRCONF_MEM_ASSIGNED	0x00000008
> -#define DRCONF_MEM_AI_INVALID	0x00000040
> -#define DRCONF_MEM_RESERVED	0x00000080
> +#define DRCONF_MEM_ASSIGNED		0x00000008
> +#define DRCONF_MEM_AI_INVALID		0x00000040
> +#define DRCONF_MEM_RESERVED		0x00000080
> +
> +struct of_drconf_cell_v2 {
> +	u32	num_seq_lmbs;
> +	u64	base_addr;
> +	u32	drc_index;
> +	u32	aa_index;
> +	u32	flags;
> +} __attribute__((packed));
> +
> +
> +static inline int dyn_mem_v2_len(int entries)
> +{
> +	int drconf_v2_cells = (n_mem_addr_cells + 4);
> +	int drconf_v2_cells_len = (drconf_v2_cells * sizeof(unsigned int));
> +	return (((entries) * drconf_v2_cells_len) +
> +                (1 * sizeof(unsigned int)));
> +}
> +
> +extern void read_drconf_cell_v2(struct of_drconf_cell_v2 *drmem,
> +				const __be32 **cellp);
> +extern void read_one_drc_info(int **info, char **drc_type, char **drc_name,
> +			unsigned long int *fdi_p, unsigned long int *nsl_p,
> +			unsigned long int *si_p, unsigned long int *ldi_p);
>  

These two functions, read_drconf_cell_v2 and read_one_drc_info, are defined
in this patch but are not used. I think it makes more sense to introduce
new functionality in the patch that uses that functionality.

>  /*
>   * There are two methods for telling firmware what our capabilities are.
> diff --git a/arch/powerpc/mm/numa.c b/arch/powerpc/mm/numa.c
> index 669a15e..ad294ce 100644
> --- a/arch/powerpc/mm/numa.c
> +++ b/arch/powerpc/mm/numa.c
> @@ -57,8 +57,10 @@
>  EXPORT_SYMBOL(node_data);
>  
>  static int min_common_depth;
> -static int n_mem_addr_cells, n_mem_size_cells;
> +int n_mem_addr_cells;
> +static int n_mem_size_cells;
>  static int form1_affinity;
> +EXPORT_SYMBOL(n_mem_addr_cells);
>  
>  #define MAX_DISTANCE_REF_POINTS 4
>  static int distance_ref_points_depth;
> @@ -405,6 +405,24 @@ static void read_drconf_cell(struct of_drconf_cell *drmem, const __be32 **cellp)
>  
>  	*cellp = cp + 4;
>  }
> + 
> + /*
> + * Retrieve and validate the ibm,dynamic-memory property of the device tree.
> + * Read the next memory block set entry from the ibm,dynamic-memory-v2 property
> + * and return the information in the provided of_drconf_cell_v2 structure.
> + */
> +void read_drconf_cell_v2(struct of_drconf_cell_v2 *drmem, const __be32 **cellp)
> +{
> +	const __be32 *cp = (const __be32 *)*cellp;
> +	drmem->num_seq_lmbs = be32_to_cpu(*cp++);
> +	drmem->base_addr = read_n_cells(n_mem_addr_cells, &cp);
> +	drmem->drc_index = be32_to_cpu(*cp++);
> +	drmem->aa_index = be32_to_cpu(*cp++);
> +	drmem->flags = be32_to_cpu(*cp++);
> +
> +	*cellp = cp;
> +}
> +EXPORT_SYMBOL(read_drconf_cell_v2);
>  
>  /*
>   * Retrieve and validate the ibm,dynamic-memory property of the device tree.
> diff --git a/arch/powerpc/kernel/prom.c b/arch/powerpc/kernel/prom.c
> index 946e34f..b6f8ae5 100644
> --- a/arch/powerpc/kernel/prom.c
> +++ b/arch/powerpc/kernel/prom.c
> @@ -441,12 +442,12 @@ static int __init early_init_dt_scan_chosen_ppc(unsigned long node,
>  
>  #ifdef CONFIG_PPC_PSERIES
>  /*
> - * Interpret the ibm,dynamic-memory property in the
> - * /ibm,dynamic-reconfiguration-memory node.
> + * Interpret the ibm,dynamic-memory property/ibm,dynamic-memory-v2
> + * in the /ibm,dynamic-reconfiguration-memory node.
>   * This contains a list of memory blocks along with NUMA affinity
>   * information.
>   */
> -static int __init early_init_dt_scan_drconf_memory(unsigned long node)
> +static int __init early_init_dt_scan_drconf_memory_v1(unsigned long node)
>  {
>  	const __be32 *dm, *ls, *usm;
>  	int l;
> @@ -516,6 +517,73 @@ static int __init early_init_dt_scan_drconf_memory(unsigned long node)
>  	memblock_dump_all();
>  	return 0;
>  }
> +
> +static int __init early_init_dt_scan_drconf_memory_v2(unsigned long node)
> +{
> +	const __be32 *dm, *ls;
> +	int l;
> +	unsigned long num_sets;
> +	u64 size, base, memblock_size;
> +
> +	ls = of_get_flat_dt_prop(node, "ibm,lmb-size", &l);
> +	if (ls == NULL || l < dt_root_size_cells * sizeof(__be32))
> +		return 0;
> +	memblock_size = dt_mem_next_cell(dt_root_size_cells, &ls);

We do the same thing in early_init_dt_scan_drconf_memory_v1 to retrieve
the memblock_size, perhaps it makes sense to break this out into a
helper routine.

> +
> +	dm = of_get_flat_dt_prop(node, "ibm,dynamic-memory-v2", &l);
> +	if (dm == NULL || l < sizeof(__be32))
> +		return 0;
> +
> +	num_sets = of_read_number(dm++, 1);
> +	if (l < (num_sets * (dt_root_addr_cells + 4) + 1) * sizeof(__be32))

Perhaps a comment here to help understand the calculation without having
to look up the format of the dynamic-mnemory-v2 device tree format.

-Nathan

> +		return 0;
> +
> +	if (n_mem_addr_cells == 0)
> +		n_mem_addr_cells = dt_root_addr_cells;
> +
> +	for (; num_sets != 0; --num_sets) {
> +		struct of_drconf_cell_v2 drmem;
> +		unsigned long nsl;
> +
> +		read_drconf_cell_v2(&drmem, &dm);
> +		base = drmem.base_addr;
> +		nsl = drmem.num_seq_lmbs;
> +		size = memblock_size;
> +
> +		/* SKip this block if the reserved bit is set in flags
> +		 * or if the block is not assigned to this partition
> +		 */
> +		if ((drmem.flags & DRCONF_MEM_RESERVED) ||
> +		    !(drmem.flags & DRCONF_MEM_ASSIGNED))
> +			continue;
> +
> +		for (; nsl != 0; nsl--) {
> +			size = memblock_size;
> +
> +			if (iommu_is_off) {
> +				if (base >= 0x80000000ul)
> +					continue;
> +				if ((base + size) > 0x80000000ul)
> +					size = 0x80000000ul - base;
> +			}
> +			memblock_add(base, size);
> +
> +			base += size;
> +		}
> +	}
> +
> +	memblock_dump_all();
> +	return 0;
> +}
> +
> +static int __init early_init_dt_scan_drconf_memory(unsigned long node)
> +{
> +	if (firmware_has_feature(FW_FEATURE_DYN_MEM_V2))

Will this check still work?

I believe the goal is to convert the dynamic-memory-v2 property
back to the current dynamic-memory property update and manage memory
with that. This allows us to not have to worry about kexec during
parse of the -v2 property. On a kexec boot though, will this test for
FW_FEATURE_DYN_MEM_V2 succeed even though we would have a -v1
version of the property. Perhaps the test should be for the
existence of the -v2 property.

-Nathan

> +		return early_init_dt_scan_drconf_memory_v2(node);
> +	else
> +		return early_init_dt_scan_drconf_memory_v1(node);
> +}
> +
>  #else
>  #define early_init_dt_scan_drconf_memory(node)	0
>  #endif /* CONFIG_PPC_PSERIES */
> 
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