xref: /linux/drivers/gpu/drm/lima/lima_pmu.c (revision 37744feebc086908fd89760650f458ab19071750)
1 // SPDX-License-Identifier: GPL-2.0 OR MIT
2 /* Copyright 2017-2019 Qiang Yu <yuq825@gmail.com> */
3 
4 #include <linux/iopoll.h>
5 #include <linux/device.h>
6 
7 #include "lima_device.h"
8 #include "lima_pmu.h"
9 #include "lima_regs.h"
10 
11 #define pmu_write(reg, data) writel(data, ip->iomem + reg)
12 #define pmu_read(reg) readl(ip->iomem + reg)
13 
14 static int lima_pmu_wait_cmd(struct lima_ip *ip)
15 {
16 	struct lima_device *dev = ip->dev;
17 	int err;
18 	u32 v;
19 
20 	err = readl_poll_timeout(ip->iomem + LIMA_PMU_INT_RAWSTAT,
21 				 v, v & LIMA_PMU_INT_CMD_MASK,
22 				 100, 100000);
23 	if (err) {
24 		dev_err(dev->dev, "timeout wait pmd cmd\n");
25 		return err;
26 	}
27 
28 	pmu_write(LIMA_PMU_INT_CLEAR, LIMA_PMU_INT_CMD_MASK);
29 	return 0;
30 }
31 
32 int lima_pmu_init(struct lima_ip *ip)
33 {
34 	int err;
35 	u32 stat;
36 
37 	pmu_write(LIMA_PMU_INT_MASK, 0);
38 
39 	/* If this value is too low, when in high GPU clk freq,
40 	 * GPU will be in unstable state.
41 	 */
42 	pmu_write(LIMA_PMU_SW_DELAY, 0xffff);
43 
44 	/* status reg 1=off 0=on */
45 	stat = pmu_read(LIMA_PMU_STATUS);
46 
47 	/* power up all ip */
48 	if (stat) {
49 		pmu_write(LIMA_PMU_POWER_UP, stat);
50 		err = lima_pmu_wait_cmd(ip);
51 		if (err)
52 			return err;
53 	}
54 	return 0;
55 }
56 
57 void lima_pmu_fini(struct lima_ip *ip)
58 {
59 
60 }
61