2019-12-02 04:44:39

by Andrew Jeffery

[permalink] [raw]
Subject: [PATCH] soc: aspeed: Fail probe of lpc-ctrl if reserved memory is not aligned

Alignment is a hardware constraint of the LPC2AHB bridge, and misaligned
reserved memory will present as corrupted data.

Signed-off-by: Andrew Jeffery <[email protected]>
---
drivers/soc/aspeed/aspeed-lpc-ctrl.c | 13 +++++++++++++
1 file changed, 13 insertions(+)

diff --git a/drivers/soc/aspeed/aspeed-lpc-ctrl.c b/drivers/soc/aspeed/aspeed-lpc-ctrl.c
index 01ed21e8bfee..fec17948cda0 100644
--- a/drivers/soc/aspeed/aspeed-lpc-ctrl.c
+++ b/drivers/soc/aspeed/aspeed-lpc-ctrl.c
@@ -4,6 +4,7 @@
*/

#include <linux/clk.h>
+#include <linux/log2.h>
#include <linux/mfd/syscon.h>
#include <linux/miscdevice.h>
#include <linux/mm.h>
@@ -241,6 +242,18 @@ static int aspeed_lpc_ctrl_probe(struct platform_device *pdev)

lpc_ctrl->mem_size = resource_size(&resm);
lpc_ctrl->mem_base = resm.start;
+
+ if (!is_power_of_2(lpc_ctrl->mem_size)) {
+ dev_err(dev, "Reserved memory size must be a power of 2, got %zu\n",
+ (size_t)lpc_ctrl->mem_size);
+ return -EINVAL;
+ }
+
+ if (!IS_ALIGNED(lpc_ctrl->mem_base, lpc_ctrl->mem_size)) {
+ dev_err(dev, "Reserved memory must be naturally aligned for size %zu\n",
+ (size_t)lpc_ctrl->mem_size);
+ return -EINVAL;
+ }
}

lpc_ctrl->regmap = syscon_node_to_regmap(
--
2.20.1