[PATCH 2/2] hwmon: xgene: Support PCC shared memory in IO region

[Hoan Tran <hotran@apm.com>]

As the PCC shared memory could be in IO region which doesn't
support caching, this patch simply uses ioremap() for IO region.

Signed-off-by: Hoan Tran <hotran@apm.com>
---
 drivers/hwmon/xgene-hwmon.c | 14 +++++++++++---
 1 file changed, 11 insertions(+), 3 deletions(-)

diff --git a/drivers/hwmon/xgene-hwmon.c b/drivers/hwmon/xgene-hwmon.c
index 5cd327e..2dac1ed 100644
--- a/drivers/hwmon/xgene-hwmon.c
+++ b/drivers/hwmon/xgene-hwmon.c
@@ -32,6 +32,7 @@
 #include <linux/kfifo.h>
 #include <linux/mailbox_controller.h>
 #include <linux/mailbox_client.h>
+#include <linux/memblock.h>
 #include <linux/module.h>
 #include <linux/of.h>
 #include <linux/platform_device.h>
@@ -135,6 +136,14 @@ static u16 xgene_word_tst_and_clr(u16 *addr, u16 mask)
 	return ret;
 }
 
+static void __iomem *pcc_ioremap(phys_addr_t phys, size_t size)
+{
+	if (!memblock_is_memory(phys))
+		return ioremap(phys, size);
+
+	return memremap(phys, size, MEMREMAP_WB);
+}
+
 static int xgene_hwmon_pcc_rd(struct xgene_hwmon_dev *ctx, u32 *msg)
 {
 	struct acpi_pcct_shared_memory *generic_comm_base = ctx->pcc_comm_addr;
@@ -690,9 +699,8 @@ static int xgene_hwmon_probe(struct platform_device *pdev)
 		 */
 		ctx->comm_base_addr = cppc_ss->base_address;
 		if (ctx->comm_base_addr) {
-			ctx->pcc_comm_addr = memremap(ctx->comm_base_addr,
-							cppc_ss->length,
-							MEMREMAP_WB);
+			ctx->pcc_comm_addr = pcc_ioremap(ctx->comm_base_addr,
+							 cppc_ss->length);
 		} else {
 			dev_err(&pdev->dev, "Failed to get PCC comm region\n");
 			rc = -ENODEV;
-- 
1.9.1