powerpc: Use NULL instead of 0 for null pointers

Sparse reports several uses of 0 for pointer arguments and comparisons.
Replace with NULL to better convey the intent. Remove entirely if a
comparison to follow the kernel style of implicit boolean conversions.
Signed-off-by: Benjamin Gray <bgray@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20231011053711.93427-5-bgray@linux.ibm.com

arch/powerpc/kernel/setup_64.c

@@ -364,7 +364,7 @@ void __init early_setup(unsigned long dt_ptr)
 	 */
 	initialise_paca(&boot_paca, 0);
 	fixup_boot_paca(&boot_paca);
-	WARN_ON(local_paca != 0);
+	WARN_ON(local_paca);
 	setup_paca(&boot_paca); /* install the paca into registers */
 
 	/* -------- printk is now safe to use ------- */

arch/powerpc/kvm/book3s_xive_native.c

@@ -567,7 +567,7 @@ static int kvmppc_xive_native_set_queue_config(struct kvmppc_xive *xive,
 	u8 priority;
 	struct kvm_ppc_xive_eq kvm_eq;
 	int rc;
-	__be32 *qaddr = 0;
+	__be32 *qaddr = NULL;
 	struct page *page;
 	struct xive_q *q;
 	gfn_t gfn;

arch/powerpc/net/bpf_jit_comp.c

@@ -146,9 +146,9 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *fp)
 	 * update ctgtx.idx as it pretends to output instructions, then we can
 	 * calculate total size from idx.
 	 */
-	bpf_jit_build_prologue(0, &cgctx);
+	bpf_jit_build_prologue(NULL, &cgctx);
 	addrs[fp->len] = cgctx.idx * 4;
-	bpf_jit_build_epilogue(0, &cgctx);
+	bpf_jit_build_epilogue(NULL, &cgctx);
 
 	fixup_len = fp->aux->num_exentries * BPF_FIXUP_LEN * 4;
 	extable_len = fp->aux->num_exentries * sizeof(struct exception_table_entry);

arch/powerpc/perf/imc-pmu.c

@@ -544,7 +544,7 @@ static int nest_imc_event_init(struct perf_event *event)
 			break;
 		}
 		pcni++;
-	} while (pcni->vbase != 0);
+	} while (pcni->vbase);
 
 	if (!flag)
 		return -ENODEV;

arch/powerpc/platforms/4xx/soc.c

@@ -112,7 +112,7 @@ static int __init ppc4xx_l2c_probe(void)
 	}
 
 	/* Install error handler */
-	if (request_irq(irq, l2c_error_handler, 0, "L2C", 0) < 0) {
+	if (request_irq(irq, l2c_error_handler, 0, "L2C", NULL) < 0) {
 		printk(KERN_ERR "Cannot install L2C error handler"
 		       ", cache is not enabled\n");
 		of_node_put(np);

arch/powerpc/platforms/pseries/lpar.c

@@ -192,9 +192,9 @@ static void free_dtl_buffers(unsigned long *time_limit)
 			continue;
 		kmem_cache_free(dtl_cache, pp->dispatch_log);
 		pp->dtl_ridx = 0;
-		pp->dispatch_log = 0;
-		pp->dispatch_log_end = 0;
-		pp->dtl_curr = 0;
+		pp->dispatch_log = NULL;
+		pp->dispatch_log_end = NULL;
+		pp->dtl_curr = NULL;
 
 		if (time_limit && time_after(jiffies, *time_limit)) {
 			cond_resched();
@@ -223,7 +223,7 @@ static void destroy_cpu_associativity(void)
 {
 	kfree(vcpu_associativity);
 	kfree(pcpu_associativity);
-	vcpu_associativity = pcpu_associativity = 0;
+	vcpu_associativity = pcpu_associativity = NULL;
 }
 
 static __be32 *__get_cpu_associativity(int cpu, __be32 *cpu_assoc, int flag)